Dissertations / Theses: 'Physico- chemical and microbiological analysis'

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Carvalho, Catharina Calochi Pires de [UNESP]. "Linguiça cuiabana: histórico e aspectos tecnológicos de fabricação." Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/88387.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
A linguiça cuiabana tem grande aceitação no município de São José do Rio Preto-SP e regiões adjacentes. Originalmente é constituída de carne bovina (corte traseiro), leite, cebolinha, pimenta bode, pimenta do reino, alho e sal refinado. Atualmente, encontramos no comércio diversos tipos de linguiça cuiabana, diferenciadas por condimentos, queijos, cortes musculares ou por espécies animais (suína, bovina, frango). No presente trabalho, juntamente com seu levantamento histórico, estudaram-se as características tecnológicas/ sensoriais da linguiça cuiabana. Foi realizado o processamento sob condições assépticas, de 4 formulações da linguiça tipo cuiabana, variando a principal matéria-prima utilizada (carne bovina, frango, suína). No processamento, as matérias-primas (bovina, frango e suína) foram cortadas em cubos que, juntamente com outros ingredientes (alho, queijo, pimenta e cebolinha), foram pesados e homogeneizados. A massa resultante foi deixada em repouso sob refrigeração por 24 horas para melhor desenvolvimento do sabor. Após descanso da massa, foi realizado o embutimento em tripas naturais. A partir destas amostras foram realizadas a caracterização do perfil físico-químico e avaliação sob refrigeração, ao longo de 7 dias de armazenamento por meio de análises microbiológicas (coliformes totais e termotolerantes (fecais), clostrídrios sulfito redutores, Salmonella spp., Staphylococcus coagulase positiva), pH, TBA. Por fim, a avaliação sensorial e estatística das diferentes linguiças tipo cuiabana processadas em laboratório. Os resultados mostraram que as variações ao longo do tempo na formulação das linguiças cuiabanas são fatores positivos, ficando evidente que as transformações são bem mais aceitas que a precursora, o que possivelmente ocorreram em função da demanda do mercado.
The cuiabana sausage has wide acceptance in the municipality of Sao Jose do Rio Preto and surrounding regions. Originally, it consisted of beef (cut back), milk, chives, goat pepper, black pepper, garlic and salt. Currently, various types of cuiabana sausage are found in trade and they are distinguished by spices, cheeses, muscle cut or animal species (bovine, chicken and swine). In this paper, along with a historical survey, we studied the technical/ sensory characteristics of cuiabana sausage. Processing was performed under aseptic conditions for 4 formulations of sausage type cuiabana, varying the main raw material (bovine, chicken and swine). In processing, the raw meat (beef, chicken and pork) was cut into cubes, which together with other ingredients (garlic, cheese, pepper and chives), were weighed and homogenized. The resulting mass was subjected to refrigeration for 24 hours in order to develop better. After the dough we rested, the inlay was inserted in natural casings. These samples were used to characterize both the physical-chemical profile and also the evaluation under refrigeration, for over a 7 days-storage in order to assess microbiological contamination (total coliforms and thermotolerant (fecal), sulphite reducing clostrídrios, Salmonella spp. , Staphylococcus coagulase positive), pH, TBA. Finally, the sensory evaluation and statistics of the different types of cuiabana sausage processed in the laboratory were performed. The results showed that changes over time in the formulation of cuiabana sausages are positive factors, demonstrating, thus, that the changes are much more accepted than the precursor, which possibly occurred as a function of market demand.

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Hervatin, Heloisa Litholdo. "Avaliação microbiologica e fisico-quimica do polen apicola in natura e desidratado sob diferentes temperaturas." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/254730.

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Orientador: Lucia Regina Durrant
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: O pólen apícola é a aglutinação do pólen presente nas flores coletados pelas abelhas operarias, e depositados na entrada da colméia. O estudo visou avaliar a qualidade microbiológica e físico-química do pólen IN NATURA e do submetido a diferentes processos de secagem, simulando as condições de processamento do produto comercializado. Também avaliou as amostras adquiridas no comercio do estado de São Paulo. Registrou-se a escassez das pesquisas sobre a qualidade microbiológica do pólen apícola. Primeiramente a pesquisa, analisou amostras de pólen apícola obtidas através de coletores instalados nas colméias pertencentes ao apiário experimental do Pólo Regional de Desenvolvimento Tecnológico dos Agronegócios do Vale do Paraíba, localizado em Pindamonhangaba-SP, pertencente à Agência Paulista de Tecnologia dos Agronegócios. A coleta ocorreu nos intervalos de 24horas, 48horas e 72horas, objetivando a presença e/ou quantidade de microrganismos patogênicos no pólen com relação ao tempo de permanência do produto no campo. As amostras foram congeladas por 48horas, e submetidas a dois processos de secagem (circulação de ar em sistema aberto a 40-42°C e sistema de circulação de ar fechado a 30°C). Foram realizadas as análises físico-químicas para os parâmetros de pH, umidade e atividade de água e as microbiológicas com avaliação de Bacillus cereus, Estafilococos coagulase positiva, coliformes a 45°C, Escherichia coli, Salmonella sp, bolores e leveduras, além de microrganismos sulfitos redutores. Amostras de pólen apícola desidratado foram adquiridas no mercado vajerista do Estado de São Paulo, com registro no Serviço de Inspeção Federal (SIF), submetidas aos mesmos parâmetros. Através dos cálculos estatísticos observaram-se possíveis diferenças e/ou correlações existentes entre os parâmetros analisados (microbiológicos, físico-químicos) para os tratamentos propostos (frequência de coleta e processos de desidratação). Verificou-se que as amostras analisadas, as IN NATURA e as desidratadas, mostraram-se isentas dos principais patógenos como Salmonella sp e Estafilococos coagulase positiva, porém, a população de bolores e leveduras foi relativamente elevada. Podendo concluir que os bolores e leveduras são os parâmetros microbiológicos mais significativos para o pólen apícola, seguido por Bacillus cereus e por bactérias coliformes totais, sendo parâmetros que devem ser introduzidos na legislação; além do processo de desidratação normalmente utilizado para pólen, não reduzir a população fúngica. Com base na Legislação atual para padrões microbiológicos em alimentos, considerando o grupo da granola, todas as amostras analisadas, encontram-se dentro dos padrões estabelecidos. Bolores e leveduras não estão incluídos na Legislação do MAPA. A época do ano teve influência na contaminação de Bolores e Leveduras, paralelamente com o tempo de permanência do pólen no campo, sendo indicada a coleta do material a cada 24horas. Assim os processos de secagem devem ser otimizados para permitirem a obtenção de produto livre de contaminantes microbiológicos; juntamente com a higienização do material nas diferentes etapas de produção e processamento do pólen, com foco na busca de materiais que substituam a madeira que é extremamente porosa, de forma a permitir higienização adequada e satisfatória. Outro parâmetro a ser considerado é a embalagem para o produto que merece atenção de especialistas nesta área
Abstract: The bee pollen is the agglutination of pollen present in flowers collected worker bees, and deposited at the entrance of the hive. The study aimed to evaluate the microbiological quality and physico-chemistry of the pollen in nature and subject to different processes of drying, simulating the processing conditions of the product sold. Also evaluated the samples acquired in the trade of the state. We have registered the scarcity of research on the microbiological quality of bee pollen. First the research, analyzed samples of bee pollen obtained from collectors installed in the experimental apiary hives belonging to the Regional Technology Development Center of Agribusiness of the Paraíba Valley, located in Pindamonhangaba-SP, belonging to the Agency of Technology Agribusiness Paulista. Frequency of collection in intervals of 24 hours, 48 hours and 72 hours, to the presence and/or amount of pathogenic microorganisms in pollen with the time of product in the field. The samples were frozen by 48 hours, and subjected to two drying processes (movement of air in the open system 40-42°C and a system of closed circulation of air at 30°C). Performed the analysis for the physical-chemical parameters of pH, humidity and water activity and with the microbiological assessment of Bacillus cereus, Coagulase positive Staphylococci, coliforms at 45°C, Escherichia coli, Salmonella, molds and yeasts, and micro sulphites reducing. Acquired samples of dried bee pollen market of the State of São Paulo, with registration at the Federal Inspection Service (SIF), subject to the same parameters. Through statistical calculations were observed possible differences and/or correlations between the analyzed parameters (microbiological, physico-chemical) for the proposed treatments (frequency of collection and processes of dehydration). It was found that the samples analyzed, the IN NATURE and dehydrated, were free of major pathogens such as Salmonella and Coagulase positive Staphylococci, however, the population of yeasts and molds is relatively high. May conclude that the yeasts and molds are the most significant microbiological parameters for the bee pollen, followed by Bacillus cereus bacteria and total coliforms, and parameters to be introduced into legislation, in addition to the dehydration process typically used for pollen, is not able to eliminate fungal its population, based on current legislation for microbiological standards in food, considering the group of granola, all the samples, are within the standards set. Yeast and molds are not included in the legislation of the MAP. The time of year influences the contamination of molds and yeasts, along with the time of pollen in the field, being given the collection of material every 24 hours. Thus the process of drying must be optimized to allow the achievement of product free of microbiological contaminants, together with the cleaning of equipment in various stages of production and processing of pollen constantly, with a focus in the search for materials to replace the wood that is extremely porous to enable proper cleaning and satisfactory. Another parameter to be considered is the packaging for the product deserves the attention of specialists in this area
Mestrado
Mestre em Ciência de Alimentos

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Souza, Alan Kardec de. "Características microbiológicas, físico-químicas e sensoriais do leite de cabra submetido à pasteurização e ao congelamento comercializados em Alfenas." Universidade Jose do Rosario Vellano, 2012. http://tede2.unifenas.br:8080/jspui/handle/jspui/131.

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Goat's milk is a complete food, rich in proteins, fats, vitamins and minerals. Having very small lipid molecules, it is highly digestible when compared to other types of milk. One of the great challenges for the popularization of goat milk is that many potential consumers reject it because of its odor, flavor and high price when compared to pasteurized cow milk. This study aimed at analyzing the quality of the milk commercialized in Alfenas, MG, Brazil and evaluating the effect of pasteurization and freezing on its microbiological, physico-chemical and sensory characteristics. During 270 days, 3 batches of raw, pasteurized, and pasteurized and frozen goat milk were analyzed. Each batch was assessed every 90 days. The data were submitted to ANOVA and the Tukey test. The results showed that the slow pasteurization was effective in improving the microbiological quality of the milk, while no change was found in freezing it for 90 days. The physico-chemical and sensory characteristics of the milk was not changed by pasteurization and 90-day freezing. It was concluded that the goat milk commercialized in Alfenas, MG, Both pasteurized and pasteurized and frozen, have microbiological, physico-chemical and sensory quality within the standards established by law.
O leite de cabra é um alimento completo, rico em proteínas, gorduras, vitaminas e sais minerais, possui moléculas de gordura de tamanho reduzido, apresentando alta digestibilidade comparado aos demais tipos de leites. Um dos maiores desafios para a popularização do leite de cabra é a grande rejeição por parte do público consumidor em potencial, devido ao forte odor, sabor e preço elevado comparado ao leite de vaca pasteurizado. Este trabalho objetivou analisar a qualidade do leite de cabra comercializado na cidade de Alfenas-MG e avaliar o efeito da pasteurização e do congelamento sobre suas características microbiológicas, físico-químicas e sensoriais. Durante 270 dias, foram realizadas análises microbiológicas, físico-químicas e sensoriais de 3 lotes de leite de cabra cru, pasteurizado e pasteurizado e congelado. Cada lote foi analisado a cada 90 dias. Os dados obtidos foram submetidos à análise de variância e teste de Tukey. Verificou-se que a pasteurização lenta foi eficiente para melhorar a qualidade microbiológica do leite e que o congelamento por 90 dias não a alterou. As características físico-químicas e sensoriais não foram alteradas pela pasteurização e nem após o congelamento por 90 dias. Concluiu-se que o leite de cabra, pasteurizado e pasteurizado e congelado, comercializado na cidade de Alfenas-MG possui qualidade microbiológica, físico-química e sensorial dentro dos padrões estabelecidos pela legislação.

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Carvalho, Catharina Calochi Pires de. "Linguiça cuiabana : histórico e aspectos tecnológicos de fabricação /." São José do Rio Preto : [s.n.], 2009. http://hdl.handle.net/11449/88387.

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Resumo: A linguiça cuiabana tem grande aceitação no município de São José do Rio Preto-SP e regiões adjacentes. Originalmente é constituída de carne bovina (corte traseiro), leite, cebolinha, pimenta bode, pimenta do reino, alho e sal refinado. Atualmente, encontramos no comércio diversos tipos de linguiça cuiabana, diferenciadas por condimentos, queijos, cortes musculares ou por espécies animais (suína, bovina, frango). No presente trabalho, juntamente com seu levantamento histórico, estudaram-se as características tecnológicas/ sensoriais da linguiça cuiabana. Foi realizado o processamento sob condições assépticas, de 4 formulações da linguiça tipo cuiabana, variando a principal matéria-prima utilizada (carne bovina, frango, suína). No processamento, as matérias-primas (bovina, frango e suína) foram cortadas em cubos que, juntamente com outros ingredientes (alho, queijo, pimenta e cebolinha), foram pesados e homogeneizados. A massa resultante foi deixada em repouso sob refrigeração por 24 horas para melhor desenvolvimento do sabor. Após descanso da massa, foi realizado o embutimento em tripas naturais. A partir destas amostras foram realizadas a caracterização do perfil físico-químico e avaliação sob refrigeração, ao longo de 7 dias de armazenamento por meio de análises microbiológicas (coliformes totais e termotolerantes (fecais), clostrídrios sulfito redutores, Salmonella spp., Staphylococcus coagulase positiva), pH, TBA. Por fim, a avaliação sensorial e estatística das diferentes linguiças tipo cuiabana processadas em laboratório. Os resultados mostraram que as variações ao longo do tempo na formulação das linguiças cuiabanas são fatores positivos, ficando evidente que as transformações são bem mais aceitas que a precursora, o que possivelmente ocorreram em função da demanda do mercado.
Abstract: The cuiabana sausage has wide acceptance in the municipality of Sao Jose do Rio Preto and surrounding regions. Originally, it consisted of beef (cut back), milk, chives, goat pepper, black pepper, garlic and salt. Currently, various types of cuiabana sausage are found in trade and they are distinguished by spices, cheeses, muscle cut or animal species (bovine, chicken and swine). In this paper, along with a historical survey, we studied the technical/ sensory characteristics of cuiabana sausage. Processing was performed under aseptic conditions for 4 formulations of sausage type cuiabana, varying the main raw material (bovine, chicken and swine). In processing, the raw meat (beef, chicken and pork) was cut into cubes, which together with other ingredients (garlic, cheese, pepper and chives), were weighed and homogenized. The resulting mass was subjected to refrigeration for 24 hours in order to develop better. After the dough we rested, the inlay was inserted in natural casings. These samples were used to characterize both the physical-chemical profile and also the evaluation under refrigeration, for over a 7 days-storage in order to assess microbiological contamination (total coliforms and thermotolerant (fecal), sulphite reducing clostrídrios, Salmonella spp. , Staphylococcus coagulase positive), pH, TBA. Finally, the sensory evaluation and statistics of the different types of cuiabana sausage processed in the laboratory were performed. The results showed that changes over time in the formulation of cuiabana sausages are positive factors, demonstrating, thus, that the changes are much more accepted than the precursor, which possibly occurred as a function of market demand.
Orientador: Pedro Fernando Romanelli
Coorientador: José Francisco Lopes Filho
Banca: Elizeu Antonio Rossi
Banca: Fernando Leite Hoffmann
Mestre

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Brandão, William Arthur Philip L. Naidoo Terroso de Mendonça. "Desenvolvimento, caracterização e otimização de bebida fermentada simbiótica de soja com farinha de banana verde." Universidade Estadual do Oeste do Parana, 2015. http://tede.unioeste.br:8080/tede/handle/tede/248.

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This work was conducted with the objective of developing and evaluate the physico-chemical, sensory and microbiological quality of fermented beverages by probiotic microorganisms, with water-soluble extract of soybean powder (8, 10, 12%), and 0, 2, 3 and 4 % addition of green banana flour powder, and 12% of sucrose in all formulations, proposing a good development of total lactic acid bacteria , through the investigation of the influence of two variables (different percentages of soy and banana flour) on the total of lactic acid bacteria count , and the physical and chemical aspects, and the sensory acceptance as well. Twelve treatments were developed. Fermented beverages of soybeans were evaluated at pH, lactic acid acidity, moisture, ash, lipids, protein, total carbohydrates, dietary fiber, water activity, fixed mineral residue, enumeration of lactic acid bacteria, total coliform count( 35° C and 45° C), yeast and mould count, sensory acceptance (hedonic scale of nine points). The results were submitted to ANOVA and Tukey test (the significance level 5. The data obtained, showed that the percentage of water-soluble soybean extract influenced in the total count of lactic acid bacteria, mainly in 10 treatments added with this ingredient. The same occurred in the treatments with addition of 1%, 2%, 3% of banana flour powde. Under the microbiological point of view, all samples were able to be consumed, according to the current legislation, during 35 days of storage. The treatment with 10% of soy extract and 3% of banana flour, presented the best results in teh microbiological count of lactic acid bacteria, however when optimized, the behavior were equal among all treatments, changing only the threshold count. Soy has sensory features that limit it´s consumption, as the beany taste and aroma, due to the action of the lipoxigenases enzymes, however, the products developed, in this study, presented a satisfactory acceptability.
Este trabalho foi realizado com o objetivo de desenvolver e avaliar as características físicoquímicas, sensoriais e a qualidade microbiológica de bebidas fermentadas por microorganismos probióticos, elaboradas com 8,10 e 12% de extrato hidrossolúvel de soja em pó, 0, 2, 3 e 4% de farinha de banana verde em pó, e 12% de sacarose em todas as formulações, propondo uma formulação com melhor desenvolvimento de bactérias láticas totais, dada a influência das duas variáveis (diferentes percentuais de soja e farinha de banana) sobre a contagem de bactérias láticas totais, em seus aspectos físico-químicos e sobre a sua aceitação sensorial. Foram desenvolvidos 12 tratamentos. As bebidas fermentadas de soja foram avaliadas quanto ao pH, acidez em ácido lático, umidade, cinzas, lipídios, proteína, carboidratos totais, fibra alimentar, atividade de água, resíduo mineral fixo, enumeração de bactérias láticas totais, contagem de coliformes a 35 ºC e 45 °C, contagem de bolores e leveduras, aceitação sensorial (escala hedônica de nove pontos). Os resultados obtidos, submetidos à ANOVA e ao teste de médias (nível de significância a 5%), revelaram que a porcentagem de adição do extrato hidrossolúvel de soja influenciou na contagem de bactérias láticas totais, principalmente nos tratamentos com 10% de adição do extrato. O mesmo ocorreu nos tratamentos com adição de 1, 2, 3% de farinha de banana em pó, nesta escala. Sob o ponto de vista microbiológico, todas as amostras estavam aptas para serem consumidas, segundo a legislação vigente, durante 35 dias de armazenamento. O tratamento com 10% de extrato de soja e 3% de farinha de banana destacou-se pelos melhores resultados na contagem microbiológica de bactérias láticas, todavia quando otimizado, o comportamento foi igual, alterando apenas o patamar da contagem. Todos os produtos desenvolvidos neste estudo apresentaram uma aceitabilidade satisfatória, com indice superior a 70% para impressão global do produto, o que significa que será bem aceito caso seja lançado no mercado consumidor

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Cunha, Maria Rosa da Silveira Mendes da. "Avaliação das condições higio-sanitárias da produção e comercialização do peixe salgado seco na cidade de Luanda." Master's thesis, Universidade de Lisboa, Faculdade de Medicina Veterinária, 2018. http://hdl.handle.net/10400.5/17389.

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Dissertação de Mestrado em Segurança Alimentar
O peixe salgado seco é um alimento bastante consumido e apreciado em Angola. Resultando do processamento de peixe fresco, é elaborado de forma artesanal, pelo que a forma como é processado e comercializado constitui uma preocupação, uma vez que são notáveis a ausência de condições hígio-sanitárias bem como de instalações adequadas à elaboração e venda do peixe salgado seco. Estas condições são favoráveis à contaminação do produto, podendo comprometer a sua qualidade e segurança sanitária e colocar em risco a saúde do consumidor. O objetivo do presente estudo foi avaliar as condições hígio-sanitárias da produção do peixe salgado seco, bem como comparar o peixe adquirido no supermercado e no mercado. Para tal, foram avaliados parâmetros microbiológicos e físico-químicos em 16 amostras de peixe salgado seco adquiridos em 4 supermercados e em 16 amostras adquiridas em 4 mercados da cidade de Luanda. Realizaram-se contagens de microrganismos Aeróbios Totais a 30°C, Enterobacteriaceae, Escherichia coli, Staphylococcus coagulase positiva, Esporos de clostrídios sulfito-redutores, Bactérias Halófilas, Bolores e Leveduras e pesquisa de Salmonella spp. Foi determinada a composição centesimal (teor de humidade, proteína, matéria gorda, cinzas, hidratos de carbono), o teor cloretos, o Índice de ácido tiobarbitúrico (TBA), a atividade da água (aw) e o pH. As condições de processamento e comercialização foram avaliadas através da realização de um inquérito e observação direta da realidade. Os resultados obtidos nas análises microbiológicas não apresentaram diferenças estatisticamente significativas (p> 0,05) entre o supermercado e o mercado. Na análise química verificou-se diferença estatística significativa (p <0,05) entre o supermercado e o mercado apenas no teor de humidade do peixe bagre. Concluiu-se que as condições hígio-sanitárias de processamento e comercialização do peixe salgado seco, devem ser melhoradas por evidenciarem possíveis riscos para saúde pública.
ABSTRACT - Dry-cured fish is a very common food in Angola that results from the manual processing of fresh fish. The way in which it is processed and commercialized is a concern, because of the lack of hygiene requisites, as well as of adequate facilities for the production and sale of dry-cured fish. This favors the contamination of the product and can compromise its quality, putting consumers’ health at risk. This study aimed to assess the hygienic conditions of dry-cured fish production, as well as to compare dry-cured fish purchased at the supermarket and at the traditional market. For such, we evaluated microbiological and physico-chemical parameters in sixteen samples of dry-cured fish purchased at four supermarkets and sixteen samples acquired in four traditional markets in the city of Luanda. For that, countings of aerobic mesophilic microorganisms, Enterobacteriaceae, Escherichia coli, Staphylococcus coagulase-positive, clostridia spores, halophile bacteria, yeasts and molds, as well as Salmonella presence were performed. The centesimal composition was determined and for that moisture content, protein, fat, ash, carbohydrates were used, together with chlorides, thiobarbituric acid index (TBA), water activity (aw) and pH determination. The processing and sale conditions were evaluated by conducting an investigation and direct observation. Microbiological and physico-chemical analysis results showed no statistically significant differences (p > 0,05) of supermarket and traditional market dry-cured fish, except for catfish’s moisture content (p < 0,05). Nvertheless, hygienic conditions of the production and sale of dry-cured fish could be improved, to reduce possible public health risks.
N/A

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Moura, Laís Simões de. "Avaliação da qualidade ambiental da água e sedimento de quatro mananciais de abastecimento público do estado de Goiás." Universidade Federal de Goiás, 2014. http://repositorio.bc.ufg.br/tede/handle/tede/4134.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
The sources of supply must have its sheltered water for contamination in obedience to CONAMA Resolution 357/2005, which regulates the standard of quality that water for public supply should have to be used by the population, after some treatment. However, the fact that the rivers act as the last destination of contaminants it is necessary analyzes the sediment to the complete assignment quality water for consumption because the contaminats coming from air, land and even their own water. Thus, the aim of this study was to evaluate the environmental quality of four sources of supply - Ribeirão Sozinha, Córrego Água Branca, Córrego dos Macacos e Ribeirão Arrozal, - located in the metropolitan area of Goiânia / GO. The study was divided into four sections. The first chapter discussed the importance of sediment analysis in the discussion of water quality and found that over a period of ten years, the number of published studies that analyzed the sediment is small, but the numbers of related publications have increased each year. The second chapter evaluated the quality of water sources in a holistic mannerclassifying them according to the results of applying a Rapid Assessment Protocol Diversity of Habitats and some physico-chemical analysis. It was noted that these rivers are suffering from anthropic action and it can compromise the water quality of them. The third chapter measured the quality of the rivers from the results obtained from analyzes of temperature, pH, Eh, conductivity, turbidity, DO, BOD, COD, organic matter, total nitrogen, total phosphorus, total suspended solids, total solids, total dissolved solids, total coliform and Escherichia coli in water and sediment test results of pH, Eh, moisture, organic matter and sediment grain size. Thus, it was possible to evaluate the four rivers in the category of class II freshwater according to relevant legislation and, considering these parameters, they have good quality and can continue to be used for this purpose. The fourth chapter evaluated the quality of water sources in relation to the concentration of six metals in water and sediment. Concentrations of Cd, Cr and Cu were found in the water; and concentrations of Cd, Cr and Ni in the sediment disagreement the limits established by law. Thus, it was concluded that these sources, even showing signs of anthropogenic physical deterioration, still offer quality water. However, it is necessary to the continuous monitoring of this quality in order to avoid future problems to the population who depend on this water resource.
Os mananciais de abastecimento devem ter a sua água resguardada quanto à contaminação em obediência à Resolução CONAMA nº 357/2005, que regulamenta o padrão de qualidade que a água destinada ao abastecimento público deve possuir para que então seja utilizada, após algum tipo de tratamento, pela população. Entretanto, o fato dos mananciais atuarem como o destino final de contaminantes faz necessária a realização de análises nos sedimentos para a complementação da atribuição de qualidade à água que será destinada ao consumo pelo fato dele abrigar contaminantes oriundos da atmosfera, solo e até mesmo da própria água. Dessa forma, o objetivo desse trabalho foi avaliar a qualidade ambiental de quatro mananciais de abastecimento – Ribeirão Sozinha, Córrego Água Branca, Córrego dos Macacos e Ribeirão Arrozal - situados na região metropolitana de Goiânia/GO. O estudo foi dividido em quatro capítulos. O primeiro capítulo abordou a importância da análise de sedimentos na discussão da qualidade da água e revelou que em um período de dez anos, a quantidade de trabalhos publicados que analisaram o sedimento é pequena, mas os números de publicações relacionadas têm aumentado a cada ano. O segundo capítulo avaliou a qualidade dos mananciais de uma forma holística classificando-os de acordo com resultados da aplicação de um Protocolo de Avaliação Rápida da Diversidade de Habitats e de algumas análises físico-químicas, com isso percebeu-se que esses mananciais estão sofrendo com a ação antrópica e que isso pode vir a comprometer a qualidade da água dos mesmos. O terceiro capítulo avaliou a qualidade dos mananciais a partir dos resultados obtidos da realização das análises de temperatura, pH, Eh, condutividade elétrica, turbidez, OD, DBO, DQO, matéria orgânica, nitrogênio total, fósforo total, sólidos suspensos totais, sólidos totais, sólidos dissolvidos totais, coliformes totais e Escherichia coli na água e nos sedimentos foram realizadas análises de pH, Eh, umidade, matéria orgânica e granulometria no sedimento. Assim, foi possível avaliar os quatro mananciais na categoria de água doce classe II de acordo com a legislação pertinente e, considerando esses parâmetros, eles apresentam boa qualidade e podem continuar sendo usados para essa finalidade. O quarto capítulo avaliou a qualidade dos mananciais em relação à concentração de seis metais na água e sedimento. Foram encontradas concentrações de Cd, Cr e Cu, na água; e concentrações de Cd, Cr e Ni no sedimento em discordância os valores limites estabelecidos pela legislação vigente. Dessa forma, concluiu-se que esses mananciais, mesmo apresentando sinais de degradação física de origem antropogênica, ainda oferecem água de qualidade. Entretanto, faz-se necessário o monitoramento contínuo dessa qualidade a fim de se evitar problemas futuros às populações que dependem desse recurso hídrico.

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Boikhutso, Jane Motladi. "Microbiological, physico-chemical and sensory quality aspects of dairy desserts manufactured from cottage cheese." Diss., University of Pretoria, 2010. http://hdl.handle.net/2263/26061.

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Two novel strawberry cottage cheese desserts were developed in this study and evaluated regarding their microbiological, physico-chemical and sensory characteristics. The purpose of the study was to develop cottage cheese desserts, both full-fat (FFCCD) and skim milk (SMCCD) from fresh cottage cheese. Four formulations were made by adding fruit pulp to the cottage cheese. These were; treatment 1 = 0 % fruit pulp, treatment 2 = 10 % fruit pulp, treatment 3 = 20 % fruit pulp and treatment 4 = 30 % fruit pulp. All of the four treatments were found to be acceptable by a consumer panel and preference scale increased with an increase in the percentage fruit pulp added, texture and appearance. The microbiological status of the treatments was also at acceptable levels at the proposed shelf life of 21 days after which, spoilage microorganisms started to grow. The added fruit pulp increased their keeping quality by increasing the shelf life. The composition of the two desserts types was also acceptable and compared well with results from other studies. It still remains that the fat content played a major role in distinguishing the two dessert types. The effect of the fat, fruit and fat/fruit interaction was evaluated. During shelf life studies, the effect of the fat, fruit, fat/fruit, day, day/fat, day/fruit as well as the day/fat/fruit interaction was also evaluated on the microbiological, pH and titratable acidity values of the treatments with a tendency to decrease by day with an increase in the percentage fruit added. It could then be concluded that the addition of fruit pulp to the fresh cottage cheese increased its shelf life, acceptability and the new product serves as an alternative to fruit blended yogurts which exist in the market. The methods used could be adapted to a small scale and thus be part of food security programmes in South Africa. However, for the new product to partake in the dairy industry, it is recommended that the product be marketed properly.
Dissertation (MInstAgrar)--University of Pretoria, 2010.
Food Science
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Magalhães, Leila Thaís Soares. "Qualidade dos solos nas áreas de nascentes do alto curso do rio Piauitinga, Lagarto - SE." Universidade Federal de Sergipe, 2009. https://ri.ufs.br/handle/riufs/6610.

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The basin of the river Piauitinga is located in south-central portion of the state of Sergipe, being responsible for water supply in some municipalities Sergipe, which did not avoid the areas around the springs, framed as environmental protection (as forestry code ) are almost in its entirety cleared. Thus, this study seeks to characterize the soils in their local environment to serve as a benchmark for future comparisons between areas of nascent and degraded in the process of recovery and assess physical attributes, chemical and microbiological soil around the springs of this river for more understanding the dynamics of semi-physical. The sources were classified as its recharge and about their conservation status. We selected the areas for revegetation of each source and these were grouped according to their position in the landscape. The environmental and pedological characteristics of the study sites was performed by observing the local landscape, the opening of micro-trenches and tradagens soil. The soils were described and classified morphologically. Slides were prepared for x-ray diffraction of clay. Could a group of springs according to their positions of landscape and local soil characteristics below (BA), with slope horizon A (EA), slope without horizon A (ES), with slope hydromorphic (EH) and foothills of gentle slope (SE). The attributes were analyzed in samples at depths of 0 to 0.1 m and 0.1 to 0.3 m. Were determined: texture, organic particulate matter, stability of macro aggregates, mean diameter of aggregates, the value of color, pH, organic C, Ca, Ca + Mg, Mg, Al, Na, K, P, H + Al, N, sum of bases, cation exchange capacity, base saturation, Al saturation of, microbial respiration, C and N microbial biomass and enzyme activity (FDA). The similarity and / or dissimilarity among sites (spatial) was investigated by multivariate analysis "non-metric multidimensional scaling (NMS), from the distance of Sorensen. Were determined by Pearson's correlation coefficients between the axes of the NMS ordination by and between the different attributes. The sites around the headwaters of the River High Piauitinga positions are distributed in erosicionais (breaking-of-focus), and download a single case of foot gentle slope of the top of coastal tablelands. Its main features are the strong hydromorphic (Gleissolos Cambisols and Haplic Gleissolos), and / or the low level of development (Cambisols and Haplic Plinthosols, both with much skeletal material - quartz and petroplinthite - many with eroded phase). The physical, chemical and biological studied by means of multivariate analysis allowed the construction of an environmental gradient, with decreasing quality of soil in the sequence: BA, EH, EA and ES. It is believed that it is possible redefinitions of strategies for the revegetation of the upper course of the spring basin, extrapolate soil quality in areas of springs of water bodies with similar characteristics and reflect on strategies for restoring degraded areas.
A bacia hidrográfica do rio Piauitinga está localizada na porção centro-sul do estado de Sergipe, sendo responsável pelo abastecimento de água de alguns municípios sergipanos, o que não evitou que as áreas do entorno de nascentes, enquadradas como de proteção ambiental (conforme código florestal), estejam quase em sua totalidade desmatadas. Assim, o presente estudo procura caracterizar os solos locais na sua ambiência para servir como um referencial em futuras comparações entre áreas de nascentes degradadas e em processo de recuperação e avaliar atributos físicos, químicos e microbiológicos do solo no entorno de nascentes deste rio, para maior entendimento da dinâmica do meio-físico. As nascentes foram classificadas quanto a sua recarga e quanto ao seu estado de conservação. Foram selecionadas as áreas de revegetação de cada nascente e estas foram agrupados de acordo com a sua posição na paisagem. A caracterização ambiental e pedológica dos sítios de estudo foi realizada pela observação da paisagem local, pela abertura de micro-trincheiras e por tradagens dos solos. Os solos foram descritos morfologicamente e classificados. Foram confeccionadas lâminas para a difração de raios-x da fração argila. Foi possível o agrupamento das nascentes de acordo com suas posições de paisagem e das características dos solos locais em baixada (BA), encosta com horizonte A (EA), encosta sem horizonte A (ES), encosta com hidromorfismo (EH) e sopé de encosta suave (SE). Os atributos foram analisados em amostras nas profundidades de 0 a 0,1m e 0,1 a 0,3m. Foram determinados: textura, matéria orgânica particulada, estabilidade de macro agregados, diâmetro médio de agregados, valor da cor, pH, C orgânico, Ca, Ca+Mg, Mg, Al, Na, K, P, H+Al, N, soma de bases, capacidade de troca catiônica, saturação de bases, saturação de Al, respiração microbiana, C e N da biomassa microbiana e atividade enzimática (FDA). A similaridade e/ou, dissimilaridade entre os sítios (ordenamento) foi averiguada pela análise multivariada non-metric multidimensional scaling (NMS), a partir da distância de Sorensen. Determinaram-se os coeficientes de correlação de Pearson entre os eixos da ordenação por NMS e entre os diferentes atributos. Os sítios do entorno das nascentes do alto curso do rio Piauitinga estão distribuídos em posições erosicionais (quebra-de-relevo), baixadas e um único caso de sopé de encosta suave de topo de tabuleiros costeiros. Suas principais características são o forte hidromorfismo (Gleissolos e Cambissolos Háplicos gleissólicos) e/ou, o baixo grau de desenvolvimento (Cambissolos Háplicos e Plintossolos, ambos com muito material esquelético quartzo e petroplintita muitos com fase erodida). As variáveis físicas, químicas e biológicas estudadas, por meio da análise multivariada, permitiram a construção de um gradiente ambiental, com a qualidade dos solos decrescente na seqüência: BA, EH, EA e ES. Acredita-se que seja possível redefinições de estratégias para a revegetação das nascentes do alto curso dessa bacia hidrográfica, extrapolar a qualidade do solo para áreas de nascentes de cursos d água com características semelhantes e refletir sobre estratégias para restauração de áreas degradadas.

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Powell, Francis E. "Physico-chemical studies in flow analysis." Thesis, Loughborough University, 1990. https://dspace.lboro.ac.uk/2134/25925.

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The first part of this study was the characterisation of an impinging jet electrode in an amperometric detector; the device having found extensive application in flow injection analysis. A voltammetric study of the detector in the stopped flow mode was carried out and evidence is presented of restricted diffusion imposed by the shallow depth of the cell. In hydrodynamic voltammetry, the detector exhibited a gradual progression from thin-layer to wall jet behaviour as the flow rate increased. This gradation is discussed in terms of a model in which flow in the electrode chamber forms concentric rings, the streamlines being successively perpendicular, oblique and parallel to the electrode. The response of the detector and its associated equipment was studied by two experiments. Firstly, the fidelity of the electrochemical instrumentation and recording system was ascertained from its electronic response to a RC (resistance-capacitance) circuit functioning as a flow injection transport analogue. Secondly, the dynamic response of the electrochemical cell was established from an experiment using a concentration step input delivered through a short, straight manifold. The results indicated that laminar flow in the delivery tube was modified by mixing stages in the cell channel and its connections to produce a final dispersion which defines an effective detection volume of only 7μL. The electronic and cell responses indicate that the total detection system would impose little extra dispersion in a practical flow injection line. In the second part of this study, photometric titrations were carried out in a stirred tank reactor in which the volume changed linearly with time. The general relation for the concentration gradient when the tank is used as a mixing device was examined experimentally under various flow conditions. In particular, the precision of linear concentration gradients was ascertained when peristaltic pumping was employed. These gradients were utilised to titrate analyte within the tank by means of titrant delivered by pump flow with photometric detection in an exit stream. Self-indicating titrations, following changes in the absorbance of analyte, titrant or reaction product, were performed each conforming to theoretical prediction. Due to the external detection system employed, dispersion and transportation lag effects were observed and accounted for.

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Nik, Zad Sangsari Homa <1965&gt. "Fish quality assessment through the application of chemico-physical, sensory and microbiological analyses." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amsdottorato.unibo.it/5852/.

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The quality of fish products is indispensably linked to the freshness of the raw material modulated by appropriate manipulation and storage conditions, specially the storage temperature after catch. The purpose of the research presented in this thesis, which was largely conducted in the context of a research project funded by Italian Ministry of Agricultural, Food and Forestry Policies (MIPAAF), concerned the evaluation of the freshness of farmed and wild fish species, in relation to different storage conditions, under ice (0°C) or at refrigeration temperature (4°C). Several specimens of different species, bogue (Boops boops), red mullet (Mullus barbatus), sea bream (Sparus aurata) and sea bass (Dicentrarchus labrax), during storage, under the different temperature conditions adopted, have been examined. The assessed control parameters were physical (texture, through the use of a dynamometer; visual quality using a computer vision system (CVS)), chemical (through footprint metabolomics 1H-NMR) and sensory (Quality Index Method (QIM). Microbiological determinations were also carried out on the species of hake (Merluccius merluccius). In general obtained results confirmed that the temperature of manipulation/conservation is a key factor in maintaining fish freshness. NMR spectroscopy showed to be able to quantify and evaluate the kinetics for unselected compounds during fish degradation, even a posteriori. This can be suitable for the development of new parameters related to quality and freshness. The development of physical methods, particularly the image analysis performed by computer vision system (CVS), for the evaluation of fish degradation, is very promising. Among CVS parameters, skin colour, presence and distribution of gill mucus, and eye shape modification evidenced a high sensibility for the estimation of fish quality loss, as a function of the adopted storage conditions. Particularly the eye concavity index detected on fish eye showed a high positive correlation with total QIM score.
La qualità dei prodotti ittici è indispensabilmente legata alla freschezza della materia prima modulata, dalla manipolazione appropriata dalle condizioni di conservazione, specialmente la temperatura di stoccaggio dopo cattura. Lo scopo della ricerca presentata in questa tesi, che è stata condotta in gran parte nel contesto di un progetto di ricerca finanziato dal Ministero Italiano delle Politiche Agricole, Alimentari e Forestali (MIPAAF), riguarda la valutazione della freschezza di specie ittiche d'allevamento e selvatiche in relazione alle diverse condizioni di stoccaggio (campioni conservati sotto ghiaccio (0°C) o a temperatura di refrigerazione (4°C)). Vari esemplari di specie diverse, quali boga (Boops boops), triglia di fango (Mullus barbatus), orata (Sparus aurata) e spigola (Dicentrarchus labrax)), sono stati esaminati durante lo stoccaggio nelle condizioni adottate. Come parametri di controllo sono state effettuate valutazioni di tipo fisico (texture, attraverso l'uso di un dinamometro; qualità visiva utilizzando un sistema di visione del computer (CVS)), chimico (attraverso (1H-NMR)) e sensoriale (attraverso il quality index method (QIM)). Sulla specie nasello (Merluccius merluccius) sono state effettuate anche determinazioni microbiologiche. L’applicazione di queste tecniche è stata finalizzata alla valutazione delle modificazioni qualitative del prodotto. In generale, i risultati hanno mostrato che la temperatura di manipolazione/conservazione è un fattore chiave per il mantenimento della freschezza del pesce. Spettroscopia NMR ha mostrato di essere in grado di quantificare e valutare la cinetica di composti selezionati durante la degradazione pesce, anche a posteriori. Questo può essere adatto per lo sviluppo di nuovi parametri relativi alla qualità e freschezza. Dalla ricerca è emerso come lo sviluppo di metodi fisici per la valutazione della freschezza del pesce, presenti un elevato potenziale per lo sviluppo di un indice qualitativo strumentale correlato sia con gli indici chimici che sensoriali, al fine di integrare/sostituire i metodi sensoriali attualmente utilizzati.

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Carstens, Alewyn Johannes. "Evaluation of microbiological and physico-chemical quality of water from aquifers in the North West Province, South Africa." Thesis, North-West University, 2013. http://hdl.handle.net/10394/8999.

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Contamination of groundwater that is suitable for drinking is of growing concern as the water supply of South Africa is becomingincreasingly limited. This is especially the case in the North West province, with its semi – arid climate and variable rainfall patterns. The aim of the study was to evaluate the microbiological and physico – chemical qualities of groundwater obtained from selected DWA (Department of Water Affairs) monitoring boreholes in the Mooi River and Harts River catchment areas. Physico -chemical parameters included temperature, pH, electrical conductivity (EC), salinity, total dissolved solids (TDS), sulphate and nitrate concentrations. Physical parameters were measured using a calibrated submerge-able multimeter and chemical parameters using specialised kits and a spectrophotometer. Microbiological parameters included heterotrophic plate counts and total and faecal coliform enumeration. Membrane filtration and culture based methods were followed for enumeration of bacteria. During the identification procedures multiplex PCR for E. coli identification and 16S rRNA gene sequencing for identification of heterotrophic plate count bacteria and amoeba resistant bacteria were used. For antibiotic resistance, the Kirby- Bauer (1996) disk diffusion method was used. During the warm and wet season high electrical conductivity and salinity were observed in the Trimpark (65.3 mS/m; 325 ppm), School (125.1 mS/m; 644 ppm), Warrenton (166.9 mS/m; 867 ppm) and Ganspan (83.3 mS/m; 421 ppm) boreholes. Warrenton borehole had a high sulphate level (450 mg/l) as well. High chemical oxygen demand was observed in the Blaauwbank (62 mg/l) and Warrenton (98.5 mg/l) boreholes. In the dry and cold season similar observations were made for the various boreholes. Electrical conductivity and salinity levels remained high for the Trimpark (70.1 mS/m; 427.5 ppm), School (127 mS/m; 645 ppm), Warrenton (173.3 mS/m; 896.5 ppm) and Ganspan (88.1 mS/m; 444.5 ppm) boreholes. Nitrate levels for the Trimpark (14.1 mg/l) and School (137 mg/l), as well as sulphate levels for the Warrenton (325 mg/l) borehole were also high. Total coliforms, faecal streptococci and HPC bacteria were enumerated from water samples from all boreholes, except Blaauwbank where no faecal streptococci were enumerated. Faecal coliforms were enumerated from 5 of the possible 7 boreholes during a warm and wet season (Trimpark – 42 cfu/100ml; School – 2 cfu/100ml; Cemetery – 175 cfu/100ml; Warrenton – 3.84 x 10³ cfu/100ml; Ganspan – 1.9 x 10³ cfu/100ml). Indicator bacteria (FC, TC, HPC) exceeded target water quality ranges (TWQR) for drinking water in each case. During the cold and dry sampling season, faecal coliforms were enumerated mainly from the Trimpark (11 cfu/100ml) borehole. Total coliforms, faecal streptococci and HPC bacteria were enumerated from all the boreholes, except for Blaauwbank that contained no faecal streptococci or total coliforms. Enumerated indicator bacteria levels again exceeded TWQR for domestic use. Total coliform counts for the Pad dam borehole, however, complied with TWQR for domestic use. Identified E. coli were resistant to Erythromycin, Cephalothin and Amoxicillin and susceptible to Ciprofloxacin. Escherichia coli isolated from the Mooi River catchment shared the same antibiotic resistance phenotype. The most abundant HPC bacterial genus identified was Pseudomonas spp. (7 isolates). Opportunistic pathogens isolated included Pseudomonas aeruginosa, Acinetobacter, Aeromonas, Alcaligenes, Flavobacterium, Bacillus cereus and Mycobacterium spp. Varying degrees of antibiotic resistance were observed. Generally, the same pattern between the same genera were observed. All HPC isolates were resistant to Cephalothin and Amoxicillin and a lower degree Erythromycin and Streptomycin. The most abundant amoeba resistant bacteria was identified as Pseudomonas spp. Other isolates included Alcaligenes faecalis and Ochrobactrum sp. and Achromobacter sp. All of these are opportunistic pathogens, except for Achromobacter. Resistance to more antibiotics (Streptomycin, Chloramphenicol, Cephalothin, and Amoxicillin) was observed in ARBs compared to HPC (Cephalothin, Amoxicillin) from bulk water from the same borehole. The water of all the aquifers sampled is of very poor physico - chemical or microbiological quality or both. Water may be used for irrigation or livestock watering only in the case where these boreholes comply with TWQR for said purposes. Results obtained indicate that the groundwater is faecally contaminated. Amongst the bacteria, opportunistic pathogens displaying various degrees of antibiotic resistance were frequently isolated. These results indicate health risks if untreated groundwater is consumed. Therefore groundwater needs to be treated before distribution especially if the water is for human consumption.
Thesis (MSc (Environmental Sciences))--North-West University, Potchefstroom Campus, 2013.

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O'Reilly, Guzene. "Assessment of the physico-chemical and microbiological quality of household water in the Vaalharts irrigation scheme, South Africa / G. O'Reilly." Thesis, North-West University, 2012. http://hdl.handle.net/10394/9190.

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Water quality in the Vaalharts region in the Northern Cape Province, South Africa, decreased over the past few years and there was a need for the microbiological and physico-chemical assessment. This problem was identified through discussions with Vaalharts Water (Vaalharts Water User Association) in 2010 when the issue of the impact of deteriorating water quality on drinking water production was raised. It was thus important to investigate concerns of the water users association pertaining to water quality issues. The aim of this study was to assess the physico-chemical and microbiological quality of household water in the Vaalharts irrigation scheme. The main residential areas were Hartswater, Pampierstad, Jan Kempdorp and Warrenton. Faecal coliforms were detected in the raw water of all the drinking water distribution systems during 2011 and 2012. No faecal coliforms were detected in the household water during 2011. This was a very positive result, because not only did the household water comply with the SANS 241 (2011) standard (0 CFU/100ml), but the purification processes were successful by removing all the E. coli’s from the raw water. However, during March 2012 faecal coliforms were detected in the household water of Jan Kempdorp (191CFU/100ml). This could be due to point pollution and possible breakage of faecal coliforms in the distribution system. Low amounts of total coliforms were detected in the raw water of some of the drinking water distribution systems. This could be due to high amounts of other colonies (pink and purple) growing on the m-Endo agar which suppress the growth of the metallic green sheen (total coliform) colonies. The total coliform numbers complied with the SANS 241 (2011) standard of ≤10 CFU/100ml at most of the distribution systems, except for Hartswater during July 2011 (14CFU/100ml) and Warrenton during March 2012 (256 CFU/100ml). Heterotrophic plate count bacteria were very high in the household water of some of the distribution systems during 2011 and 2012 which exceeded the SANS 241 (2011) standard of ≤1000 CFU/ml. A large number of pigmented (yellow, orange, pink) and non-pigmented (white) colonies were isolated on R2A agar. This can be an indication of some failure in treatment processes. Other microbiological parameters that were tested such as faceal streptococci, Clostridia, Pseudomonas aeruginosa and fungi did not indicate any danger, but there were high levels of total anaerobic bacteria in the raw water during 2011 and 2012. A high level of anaerobic bacteria was detected in the household water of Hartswater during July 2011. Clostridia were also present in the household water of some of the distribution systems during 2011 and 2012. Sequencing results of the mdh, lacZ and uidA genes indicated that one of the isolates was identified as Enterobacter cloacae and the other isolates were E. coli. Four of the isolates were identified as Escherichia coli O104:H4. This is a pathogenic strain and raised concern. The physicochemical parameters that were measured complied with the SANS 241 (2011) standards during 2011 and 2012, but some of the parameters increased gradually from 2011 to 2012. Statistical analysis indicated that physico-chemical parameters had an influence on microbiological parameters and that deteriorating raw water may have an impact on drinking water quality. Another concern currently is that there is no SANS 241 (2011) for faecal streptococci, Clostridia, Pseudomonas aeruginosa, fungi and anaerobic bacteria. These are all opportunistic pathogenic bacteria and consuming water with high levels of these bacteria may cause health problems. This study indicated good progress in the treatment processes of the distribution systems over the two years. This may be due to the feedback given to Vaalharts Water during this study regarding the water quality of the residential areas. The physico-chemical and microbiological results of the present study indicated possible biofilm formation in the distribution systems. This may have impacts on the drinking water quality of the distribution systems. It was also evident that deteriorating raw water sources may have an impact on drinking water production.
Thesis (MSc (Environmental Sciences))--North-West University, Potchefstroom Campus, 2013.

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Pinto, Marta Filipa Pedro Guedes. "Avaliação da qualidade físico-química e microbiológica de leite pasteurizado produzido por micro empresas em Alagoas, Brasil." Master's thesis, ISA/UTL, 2011. http://hdl.handle.net/10400.5/4083.

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Mestrado em Engenharia Alimentar - Instituto Superior de Agronomia
Milk is an food product that we ingest during our lives. Mostly for beeing very complete nutritiously, what makes it, simultaneously susceptible to damage by way of development. Therefore it is essential to control it's processing. In Microbiological Food Lab of "Universidade Federal de Alagoas" there were analysed 115 samples of pasteurized milk type C, from 16 small companies, who belong to Cooperativa de Produção Leiteira de Alagoas – CPLA – who participated in the program "Fome Zero" (Zero Hunger) of the brazilian government, in which the goal is to supply this food to needed families. The physical-chemical parameters (fat content, titratable acidity,dry residue free of fat matter, 15ºC density, freezing index, protein matter, and alcohol stability) and microbiological (NMP resolve of Coliforms at 35 ºC and 45 ºC and research of Salmonella sp.) they were analysed according to Normative Instruction no. 51 (2002) and according to brazilian conventional methodology. According to the results obtained, only for 15 ºC density, dry residue free of fat matter and Salmonella spp. there were no unconformitys found. It is recommended the implementation/improvement of programs, on food manufacturing pratices, sanitation and control of critical control points, in order to ensure the safety of the final product.

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Ghelawi, Mohamed Ali. "A physico-chemical analysis of irradiated dates (Phoenix dactylifera L.)." Thesis, University of Salford, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.360402.

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16

Sarkar, Amit Kumar. "Fullerenes and non-planar graphitic networks : a physico-chemical analysis." Thesis, University of Sussex, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.387366.

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17

Mirjana, Radanović. "Kompleksi nekih prelaznih metala sa Šifovim bazama aminogvanidina." Phd thesis, Univerzitet u Novom Sadu, Prirodno-matematički fakultet u Novom Sadu, 2015. https://www.cris.uns.ac.rs/record.jsf?recordId=95548&source=NDLTD&language=en.

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U ovoj doktorskoj disertaciji opisane su sinteze novih kompleksa prelaznih metala sa piridoksiliden- (PLAG), odnosno saliciliden-aminogvanidinom (SALAG). Dobijenikompleksi su okarakterisani elementalnom analizom, IR spektrima, konduktometrijskim i magnetnim merenjima, a većina i rendgenskomstrukturnom analizom. Osim toga, dobijene su i nove forme ovih Šifovih baza, i to u vidu monokristala, čime su omogućena ispitivanja njihovih molekulskih i kristalnih struktura, kao i uporedna analiza sa koordinovanim ligandima. Sa PLAG je sintetisano 7 novi kompleksa Cu(II), a pored toga po prvi put suizolovani mono i bis(ligand) kompleksi Fe(III) i Co(III), mono(ligand) kompleksi V(V), kao i jedan kompleks Zn(II) u kojem ovaj potencijalno tridentatni ONN ligand, umonoprotonovanoj formi, ima ulogu kontra-jona. Sa stanovišta geometrije zajedničko za izolovane komplekse Cu(II) i V(V) je da imaju kvadratno-piramidalnu strukturu, sa izuzetkom jednog kvadratno-planarnog kompleksa Cu(II), dok je u kompleksima Fe(III) i Co(III) nađeno očekivano oktaedarsko okruženje centralnogjona. Pored ovih, sintetisano je i pet novih kompleksa sa SALAG, od kojih su dvakompleksa Cu(II) i kompleks V(V) okarakterisani rendgenskom strukturnomanalizom, dok je mikrokristalnim bis(ligand) kompleksima Co(III) i Ni(III) na osnovufizičko-hemijskih karakteristika predložena odgovarajuća struktura. Zajedničko za obe opisane Šifove baze je da se koordinuju na ONN tridentatni način, i to preko atoma kiseonika deprotonovane fenolne grupe i atoma azota azometinske i imino grupe AG fragmeta. Posebno je naglašeno da su saPLAG izolovana dva dimerna kompleksa Cu(II) u kojima je po prvi put nađena tetradentatna koordinacija ovog liganda, u koju je dodatno uključen atom kiseonika hidroksimetil-grupe PL-ostatka. Za razliku od SALAG, koji je u izolovanim kompleksima koordinovan isključivo kao monoanjon, nastao deprotonacijom fenolneOH-grupe, za PLAG je osim ove, potvđena koordinacija u neutralnoj, zwitter-jonskoj, ali i dvostruko deprotonovanoj formi. Zwitter-jonska forma liganda nastaje migracijom atoma vodonika sa fenolnog hidroksila na piridinski atom azota PL-ostatka, dok deprotonacijom piridinskog ili hidrazinskog atoma azota, odnosno oba pomenuta atoma nastaju monoanjon i dianjon helatnog liganda, respektivno. Na kraju, urađena su i ispitivanja antimikrobne aktivnosti odabranih jedinjenjaprema predstavnicima grampozitivnih i gramnegativnih bakterija, kao i dve kulturekvasca. Tom prilikom nije utvrđena nikakva inhibitorna aktivnost prema primenjenimbakterijskim sojevima, dok su u slučaju kvasaca izvesno mikrobicidno dejstvo pokazali samo kompleksi Cu(II).
This PhD thesis describes the syntheses of some new transition metal complexes with pyridoxilidene- (PLAG) and salicylideneaminoguanidine (SALAG). Obtained complexes are characterized by elemental analysis, IR spectroscopy, conductometric and magnetic measurements. Besides, the structural analysis of majority of the obtained complexes was performed. Some new forms of these Schiff bases are synthesized in form of single crystals, which made their X-ray analysis as well as comparison with coordinated forms possible.With PLAG, 7 new Cu(II) complexes were obtained and for the first time mono and bis(ligand) complexes of Fe(III) and Co(III) as well mono(ligand) complexes of V(V) were isolated. Furthermore, the structure of Zn(II) complex in which PLAG in its monocationic form has a role of counter ion is presented. With the exception of one Cu(II) complex, all reported Cu(II) and V(V) complexes have a square-pyramidal geometry, whilst Fe(III) and Co(III) are situated in octahedral surroundings. Also, five new complexes of Cu(II), Co(III), Ni(II) and V(V) with SALAG were synthesized. In both Cu(II) complexes and V(V) complex the expected coordination mode and geometry were confirmed by X-ray analysis, while octahedral structure of bis(ligand) complexes with Co(III) and Ni(II) was proposed based on results of physico-chemical characterization.Both PLAG and SALAG coordinate the metal ion in tridentate ONN manner, through the oxygen atom of deprotonated phenolic group and nitrogen atoms of azomethine and imino groups of AG moiety. It is also emphasized that in two dimeric Cu(II) complexes with PLAG tetradentate coordination mode was found, in which the oxygen atom of hydroxymethyl group of PL residue was additionally involved. Unlike SALAG, which is coordinated as monoanion in all of the examined complexes, PLAG can have one of three degrees of deprotonation. Zwitter-ion of PLAG is formed by migration of H-atom from phenolic oxygen to pyridine nitrogen, while the deprotonation of pyridine or/and hydrazine nitrogen, makes it mono-and dianion, respectively.Also, microbiological tests on the selected compounds were preformed. Namely, antimicrobial activity of these compounds against some gram-positive and gram-negative bacteria, as well as some yeast cultures was examined and none of the samples showed antimicrobial activity against bacteria, whilst only Cu(II) complexes showed certain inhibitory effect against yeasts.

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18

Díez, Orrite Silvia. "Physico-chemical properties of polymers at interfaces." Doctoral thesis, Universitat Rovira i Virgili, 2002. http://hdl.handle.net/10803/8511.

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A polymer is a large molecule constructed from many smaller structural units called
monomers joined together by covalent bonds. Polymers have existed in natural form
since life began and those such as DNA, RNA, proteins and polysaccharides are some
of the most important macromolecules found in plant and animal life. From the earliest
times, the man has used many of these polymers as materials for providing clothing,
decoration, tools, weapons and other requirements. However, the origins of today's
polymer industry commonly are accepted as being in the nineteenth century when
important discoveries were made concerning to the modification of certain natural
polymers, as cellulose. The use of synthetic and natural polymers as stabilisers for
colloid systems (sols, dispersions, microemulsions, etc.) is becoming more important
everyday in contemporary life. Polymer additives can be applied in preconcentrations
and dehydration of suspensions in mineral processing, purification of wastewater and
even in nutritional and pharmaceutical emulsions being their importance related to the
characteristics of the process and the properties that they show. The present work aims
to develop appropriate numerical and analytical modelling techniques, which can
describe (considering the formation of loops and tails) the structure of a polymeric layer
adsorbed on heterogeneous surfaces; this adsorbed layer is an relevant factor in the
properties showed by this kind of materials. Taking into account this, the methodology
known as Single Chain Mean Field (SCMF) (originally used to study micellar
aggregates and grafted polymers) was modified to apply on polymer adsorption
problems. In this way, it was possible to calculate numerically properties that can be
experimentally measured, such as total monomer volume fraction profiles, loop and tail
volume fraction profiles, adsorbance or the thickness of the adsorbed layer. The
structure of the polymeric layer was examined both for flat and spherical (colloidal
particles) surface geometries. When compared with other well established
methodologies for the numerical simulation of polymeric systems, this new version of
SCMF was found to be more efficient due to the improved sampling of the polymer
chain configuration space.
Thus, SCMF method results, in the case of the adsorption on flat surfaces, compare well
with those obtained either with Monte Carlo simulations or with the method developed
in the 80s by Scheutjens and Fleer (SCF). Due to the lack of studies focusing to polymer
adsorption on colloidal particles, our results have been the first to present quantitative
predictions of the structure of the polymeric layer adsorbed on a spherical surface. Thus,
we have demonstrated the dependence of the adsorbed polymer layer with the size of
the colloidal particle as well as the characteristic lengths that influence on it. Finally, in
this work an analytical approach for the description of polymer-colloidal mixtures has
been developed which compares well with the numerical results obtained from the
SCMF methodology. Furthermore, the analytical approach is able to predict system
behaviours, as for example the formation of gels.
Un polímero es una molécula de grandes dimensiones formada de pequeñas unidades
llamadas monómeros, los cuales se encuentran unidos por medio de enlaces covalentes.
Los polímeros han existido de forma natural desde el comienzo de la vida, y aquellos
como el DNA, RNA o las proteínas son algunos de los polímeros más importantes
encontrados tanto en la vida animal como en la vegetal. Desde siempre el hombre ha
utilizado muchos de estos polímeros como materiales para hacer ropa, decoración,
herramientas, etc. Sin embargo, el origen de la industria de polímeros que conocemos
hoy en día se produjo en el siglo 19, gracias a importantes descubrimientos dentro de la
modificación de ciertos polímeros naturales, como la celulosa. El uso de polímeros
sintéticos y naturales como estabilizadores de sistemas coloidales (dispersiones,
microemulsiones, etc.) juega en nuestros días un papel importante. Los polímeros
utilizados como aditivos, pueden ser aplicados en preconcentraciones y deshidratación
de suspensiones dentro de procesos minerales, tratamiento de aguas residuales e incluso
los podemos encontrar dentro de la industria farmacéutica y alimentaria, donde su
importancia es debida a la procesabilidad y propiedades que ellos exhiben. El trabajo
que se presenta es orientado al desarrollo de técnicas de modelización, tanto analíticas
como computacionales, y su aplicación en la descripción (por medio de la formación de
bucles y colas) de la estructura de la capa de polímeros adsorbida en superficies
heterogéneas, siendo dicha capa de polímeros un factor importante en las propiedades
que este tipo de materiales presentan. Con este propósito, la metodología conocida
como Single Chain Mean Field, utilizada anteriormente tanto para el estudio de
agregados micelares como de polímeros anclados en superficies, ha sido modificada
para describir la adsorción de polímeros en superficies. Así se han podido calcular
numéricamente propiedades medibles experimentalmente como los perfiles de la
fracción en volumen de monómeros totales, además de los pertenecientes a los bucles y
colas, adsorbancia o el espesor de la capa adsorbida, para geometrías de la superficie
absorbente tanto plana como esférica (partículas coloidales). En su comparación con
otras metodologías, ya establecidas para la simulación numérica dentro de la física de
polímeros, la aplicación de esta nueva versión del Single Chain Mean Field (SCMF)
ha resultado ser más eficiente debido a un mejor muestreo del espacio de
configuraciones de las cadenas poliméricas. De este modo, comparando los resultados
obtenidos a partir del SCMF, con aquellos obtenidos mediante técnicas de simulación
Monte Carlo o la teoría desarrollada en los años 80 por Scheutjens y Fleer (SCF), se ha
podido encontrar un buen acuerdo en las propiedades calculadas para el caso de la
adsorción en superficies planas. Debido a la dificultad intrínseca del estudio de la
adsorción en superficies curvadas, nuestros resultados son los primeros que presentan
predicciones cuantitativas sobre la estructura de la capa que se forma sobre una
partícula coloidal. Así hemos podido comprobar la dependencia de la estructura de la
capa de polímeros adsorbidos con el tamaño de la partícula sobre la que se encuentran
adsorbidos además de las longitudes características de las cuales depende. Finalmente,
en este trabajo se ha desarrollado, también, una teoría analítica para la descripción de la
mezcla polímero-coloide. De este modo, los resultados numéricos obtenidos con el
SCMF han podido ser comparados con dicha teoría, obteniendo, de nuevo, un buen
acuerdo y predecir, además, comportamientos colectivos como la formación de geles.

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19

Scuracchio, Paola Andressa. "Qualidade da água utilizada para consumo em escolas no município de São Carlos-SP /." Araraquara : [s.n.], 2010. http://hdl.handle.net/11449/88588.

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Orientador: Adalberto Farache Filho
Banca: João Bosco Faria
Banca: Clovis Wesley de Oliveira Souza
Resumo: Sabe-se da importância de se tratar a água destinada ao consumo humano, pois, é capaz de veicular grande quantidade de contaminantes físico-químicos e/ou biológicos, cujo consumo tem sido associado a diversos problemas de saúde. Assim, é necessário saber se a qualidade da água destinada ao consumo humano, responde as exigências da legislação. O objetivo desta pesquisa foi avaliar a qualidade da água que abastece as escolas e creches municipais da cidade de São Carlos - SP. Foram coletadas 186 amostras de água, em três pontos distintos: rede, reservatório e filtro. Para análise de coliformes totais e coliformes fecais/E. coli utilizou-se a técnica de substratos cromogênicos/Colilert; para contagem de bactérias heterotróficas foi utilizada a técnica de cultivo em profundidade; para determinação do pH adotou-se leitura direta no pHâmetro; para determinação de flúor foi utilizado o método SPANDS; para determinação de cloro utilizou-se o método DPD; para determinação de turbidez foi utilizado o método nefelométrico e para determinação da cor o método colorimétrico. Para coliformes fecais/E.coli apenas uma amostra do filtro apresentou positividade. Para coliformes totais, sete amostras (22,5%) da rede, seis (19,3%) do reservatório e seis (19,3%) do filtro apresentaram contaminação na primeira colheita e sete (22,5%) amostras da rede, três (9,6%) do reservatório e sete (22,5%) do filtro na segunda coleta. Para bactérias heterotróficas uma amostra da rede, uma do reservatório e 13 (41,9%) do filtro apresentaram contagens acima de 500UFC/ml na primeira coleta e três (9,6%) amostras da rede e do reservatório e 14 (45,1%) do filtro na segunda coleta. Para pH, cinco amostras (16,1%) da rede e uma do filtro não atenderam ao padrão exigido pela legislação na primeira coleta e sete amostras (22,6%) da rede na segunda coleta... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Today, we know the importance of treating water for human consumption, therefore, is capable of conveying large amounts of physical and chemical contaminants and / or biological agents, whose consumption has been associated with several health problems. Thus, it is necessary to know if the quality of water intended for human consumption, answers the requirements of the law. The aim of this study was to evaluate the quality of water supply schools and day care centers of São Carlos - SP. We collected 186 samples of water, on three points: network, tank and filter. For analysis of total coliform and fecal coliform / E. coli we used the technique of chromogenic substrates / Colilert; for heterotrophic bacterial count technique was used to grow in depth, to determine pH reading was adopted in direct pHâmetro; for determination of fluoride, the method SPANDS; to determine chlorine used the DPD method, for determination of turbidity nephelometric method was used to determine the color and colorimetric method. For fecal coliform / E.coli only one sample was positive filter. For total coliforms, seven samples (22.5%) of the network, six (19.3%) of the tank and six (19.3%) of the filter was contaminated in the first harvest and seven (22.5%) samples of the network three (9.6%) of the reservoir and seven (22.5%) of the filter in the second collection. Heterotrophic bacteria from a sample network, a tank and 13 (41.9%) of the filter had counts above 500UFC/ml the first harvest and three (9.6%) samples of the network and the reservoir and 14 (45, 1%) of the filter in the second harvest. For pH, five samples (16.1%) of the network and a filter did not meet the standard required by legislation in the first harvest and seven samples (22.6%) of the net in the second harvest. For fluoride 27 (87.0%) of the network, 24 (77.4%) of the reservoir and 25 (80.6%) were outside of the filter pattern in the first... (Complete abstract click electronic access below)
Mestre

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20

Scuracchio, Paola Andressa [UNESP]. "Qualidade da água utilizada para consumo em escolas no município de São Carlos-SP." Universidade Estadual Paulista (UNESP), 2010. http://hdl.handle.net/11449/88588.

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Universidade Estadual Paulista (UNESP)
Sabe-se da importância de se tratar a água destinada ao consumo humano, pois, é capaz de veicular grande quantidade de contaminantes físico-químicos e/ou biológicos, cujo consumo tem sido associado a diversos problemas de saúde. Assim, é necessário saber se a qualidade da água destinada ao consumo humano, responde as exigências da legislação. O objetivo desta pesquisa foi avaliar a qualidade da água que abastece as escolas e creches municipais da cidade de São Carlos – SP. Foram coletadas 186 amostras de água, em três pontos distintos: rede, reservatório e filtro. Para análise de coliformes totais e coliformes fecais/E. coli utilizou-se a técnica de substratos cromogênicos/Colilert; para contagem de bactérias heterotróficas foi utilizada a técnica de cultivo em profundidade; para determinação do pH adotou-se leitura direta no pHâmetro; para determinação de flúor foi utilizado o método SPANDS; para determinação de cloro utilizou-se o método DPD; para determinação de turbidez foi utilizado o método nefelométrico e para determinação da cor o método colorimétrico. Para coliformes fecais/E.coli apenas uma amostra do filtro apresentou positividade. Para coliformes totais, sete amostras (22,5%) da rede, seis (19,3%) do reservatório e seis (19,3%) do filtro apresentaram contaminação na primeira colheita e sete (22,5%) amostras da rede, três (9,6%) do reservatório e sete (22,5%) do filtro na segunda coleta. Para bactérias heterotróficas uma amostra da rede, uma do reservatório e 13 (41,9%) do filtro apresentaram contagens acima de 500UFC/ml na primeira coleta e três (9,6%) amostras da rede e do reservatório e 14 (45,1%) do filtro na segunda coleta. Para pH, cinco amostras (16,1%) da rede e uma do filtro não atenderam ao padrão exigido pela legislação na primeira coleta e sete amostras (22,6%) da rede na segunda coleta...
Today, we know the importance of treating water for human consumption, therefore, is capable of conveying large amounts of physical and chemical contaminants and / or biological agents, whose consumption has been associated with several health problems. Thus, it is necessary to know if the quality of water intended for human consumption, answers the requirements of the law. The aim of this study was to evaluate the quality of water supply schools and day care centers of São Carlos - SP. We collected 186 samples of water, on three points: network, tank and filter. For analysis of total coliform and fecal coliform / E. coli we used the technique of chromogenic substrates / Colilert; for heterotrophic bacterial count technique was used to grow in depth, to determine pH reading was adopted in direct pHâmetro; for determination of fluoride, the method SPANDS; to determine chlorine used the DPD method, for determination of turbidity nephelometric method was used to determine the color and colorimetric method. For fecal coliform / E.coli only one sample was positive filter. For total coliforms, seven samples (22.5%) of the network, six (19.3%) of the tank and six (19.3%) of the filter was contaminated in the first harvest and seven (22.5%) samples of the network three (9.6%) of the reservoir and seven (22.5%) of the filter in the second collection. Heterotrophic bacteria from a sample network, a tank and 13 (41.9%) of the filter had counts above 500UFC/ml the first harvest and three (9.6%) samples of the network and the reservoir and 14 (45, 1%) of the filter in the second harvest. For pH, five samples (16.1%) of the network and a filter did not meet the standard required by legislation in the first harvest and seven samples (22.6%) of the net in the second harvest. For fluoride 27 (87.0%) of the network, 24 (77.4%) of the reservoir and 25 (80.6%) were outside of the filter pattern in the first... (Complete abstract click electronic access below)

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21

BERA, ALEXANDRE. "Efeitos nas caracteristicas fisico-quimicas, microbiologicas e sensoriais em amostras de mel de abelhas submetidas a radiacao gama." reponame:Repositório Institucional do IPEN, 2010. http://repositorio.ipen.br:8080/xmlui/handle/123456789/9527.

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Tese (Doutoramento)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

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22

Obi, CL, MNB Momba, A. Samie, JO Igumbor, E. Green, and E. Musie. "Microbiological, physico-chemical and management parameters impinging on the efficiency of small water treatment plants in the Limpopo and Mpumalanga Provinces of South Africa." Water SA, 2007. http://encore.tut.ac.za/iii/cpro/DigitalItemViewPage.external?sp=1000861.

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In the wake of the growing dependence on small water treatment plants (SWTPs) in providing quality water to rural areas and the global burden of water borne diseases, this study sought to examine the efficiency of 55 SWTPs located in rural or peri-urban areas of Limpopo and Mpumalanga Provinces in order to gauge the safety of water supply for human consumption. The microbiological and physical parameters of raw water, treated water and water in the distribution systems were examined using standard methods. Management issues impacting on quality of water supply were determined by use of questionnaires and focus group discussions. Results obtained showed that the pH, turbidity, temperature and conductivity of the raw water in SWTPs studied in both provinces ranged between 6.46 to 9.05 pH units, 0.19 to 8.0 NTU, 15.4oC to 31.40oC and 44.40.4 μS to 108 μS respectively. Water quality compliance at point of use (treated water) according to the Department of Water Affairs and Forestry of South Africa guidelines in SWTPs studied in both provinces were 85% for faecal coliforms and 69% for total coliforms. In the distribution systems, TCCs, FCCs and HPCs were within recommended limits except for few SWTPs suggesting a possibility of inadequate treatment and this may represent post-treatment contamination and possible risk of infection from these water supply sources. Physical parameters were generally within the recommended ranges . In terms of administrative issues, some plant operators did not have adequate knowledge of the functioning of the SWTPs and most were unable to calculate chlorine dosage, determine flow rates or undertake repairs of basic equipment. Poor working conditions , frequent stock depletion of chemicals , lack of maintenance culture , lack of emergency preparedness and poor communication were also cited . The study has revealed that the microbiological quality of raw water was very poor but that water treatment was efficient in the majority of SWTPs studied in both provinces. Regular monitoring of microbial and physico-chemical parameters of water quality served by the different SWTPs to the population is recommended to gauge their safety for human consumption. Issues such as enhanced incentives and periodic training of plant operators, improved communication and conditions of service , periodic stock inventory and entrenchment of maintenance culture may be necessary to ensure sustained and efficient water distribution systems.

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23

Guerreiro, A. "Rational analysis of physico-chemical parameters affecting recognition properties of molecularly imprinted polymers." Thesis, Cranfield University, 2006. http://dspace.lib.cranfield.ac.uk/handle/1826/11014.

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Molecularly imprinted polymers (MIPs) are new type of materials with tailor made molecular recognition sites. Despite their enormous potential in separations, sensing and pharmaceutical industry, MIPs have so far failed to achieve significant commercial application. This is in part due to lack of understanding of MIPs at a molecular level, strong binding site heterogeneity and poor compatibility with aqueous solvents. This work is aimed at improving overall MIP performance and quality, with special focus on the improvement of compatibility with aqueous environment. Compatibility with aqueous solvents was achieved by (i) employing a molecular modelling step prior to polynerisation, (ii) by studying the ionic properties of the polymer and (iii) by analysis of the influence of different polymerisation conditions. The study of the pressure and magnetic field effects on polymers allowed us to produce materials with increased stability, lower binding site heterogeneity and higher affinity, as compared to standard imprinted materials. To minimise site heterogeneity imprinted nanoparticles with ca. 90 kDa were produced using a living polymerisation method. The particles with essentially uniform population of binding sites were obtained by employing affinity chromatography with immobilised template. As a model system variety of drugs were imprinted with the polymers being able to discriminate between closely related structural analogues in aqueous media. This work had substantial effect on success of project Pisarro - Piezoelectric Sensing Arrays for Biomolecular Interactions and Gas Monitoring where range of imprinted polymers were designed with high affinity to drugs of abuse. Currently 1 work is in progress aimed at application of these materials in commercial sensors for forensic use.

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24

Guerreiro, António. "Rational analysis of physico-chemical parameters affecting recognition properties of molecularly imprinted polymers." Thesis, Cranfield University, 2006. http://dspace.lib.cranfield.ac.uk/handle/1826/11014.

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Molecularly imprinted polymers (MIPs) are new type of materials with tailor made molecular recognition sites. Despite their enormous potential in separations, sensing and pharmaceutical industry, MIPs have so far failed to achieve significant commercial application. This is in part due to lack of understanding of MIPs at a molecular level, strong binding site heterogeneity and poor compatibility with aqueous solvents. This work is aimed at improving overall MIP performance and quality, with special focus on the improvement of compatibility with aqueous environment. Compatibility with aqueous solvents was achieved by (i) employing a molecular modelling step prior to polynerisation, (ii) by studying the ionic properties of the polymer and (iii) by analysis of the influence of different polymerisation conditions. The study of the pressure and magnetic field effects on polymers allowed us to produce materials with increased stability, lower binding site heterogeneity and higher affinity, as compared to standard imprinted materials. To minimise site heterogeneity imprinted nanoparticles with ca. 90 kDa were produced using a living polymerisation method. The particles with essentially uniform population of binding sites were obtained by employing affinity chromatography with immobilised template. As a model system variety of drugs were imprinted with the polymers being able to discriminate between closely related structural analogues in aqueous media. This work had substantial effect on success of project Pisarro - Piezoelectric Sensing Arrays for Biomolecular Interactions and Gas Monitoring where range of imprinted polymers were designed with high affinity to drugs of abuse. Currently 1 work is in progress aimed at application of these materials in commercial sensors for forensic use.

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Rani, Zikhona Theodora. "Effect of post-slaughter handling on physico-chemical and microbiological quality of red meat along the distribution chain in the Eastern Cape Province, South Africa." Thesis, University of Fort Hare, 2015. http://hdl.handle.net/10353/2490.

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The broad objective of the study was to investigate the effect of post-slaughter handling in the distribution chain on red meat quality and safety. A survey was conducted among 300 consumers and 100 meat handlers in five different municipalities (Buffalo City, Nkonkobe, Ngqushwa, Lukhanje and Amahlathi) in the Eastern Cape Province of South Africa to investigate their perceptions on meat quality and safety, together with challenges faced by meat handlers during the distribution of meat from the abattoir to retailers. The microbiological profile and physico-chemical quality of red meat at different stages of the abattoir to retail outlets in the distribution chain were also determined. Swabs (n=216) and meat samples (n=450) were collected from beef, pork and mutton carcasses during the loading process of carcasses into trucks at the abattoir, when offloading carcasses at the supply points and during marketing. Physico-chemical qualities such as colour (L* - lightness, b* - redness and a* - yellowness) and meat pH measurements were taken at each point. To determine the microbiological profiles of the carcasses, four microbiological parameters were considered: Total bacteria count (general bacteria), coliform count (related to hygiene and indicator for pathogens), Escherichia coli (Gram-negative pathogen) and Staphylococcus aureus (Gram-positive pathogen). Two types of packaging (vacuum and overwrapping) were used to determine their effect on shelf-life and microbiological quality of red meat under the normal marketing conditions over a storage duration of 15 days. The results from the study showed low awareness of consumers about the pathogenic diseases which arise from meat. A strong significant association (p ˂ 0.05) between educational status and awareness on meat safety was observed. Most of the consumers perceived that quality goes beyond safety such that 35.6 percent of the respondents indicated that they did not have a problem with consuming spoiled meat, whilst the remaining 64.4 percent indicated that they would r eject spoiled meat. Although retailers indicated that they take meat safety into consideration in their shops, 92 percent of the retailers revealed that they do not perform microbial assessment of meat in their shops. A series of loading and off-loading, temperature fluctuations, environmental temperatures and ques during offloading were reported as the major challenges during transportation of carcasses from the abattoir to the supply points. The microbial counts were significantly (p<0.05) higher in samples from the commercial abattoir than in those from the communal abattoir. Escherichia coli was the predominant microbial contaminant in the samples from both abattoirs. When following the chain, total bacterial count (TBC), coliform count (CC) and the levels of E. coli contamination increased progressively between the loading and the off-loading points (5.1 to 7.9 log10 CFU/cm2; 5.0 to 5.6 log10 CFU/cm2 and 2.7 to 3.7 log10 CFU/cm2, respectively). The storage period, meat type, distance during transportation and temperature were found to have a significant impact on the microbial levels during the distribution of carcasses. Distribution stage had a significant effect (p<0.05) on some of the physico- chemical meat quality attributes and differences in the lightness (L*) and redness (a*) values between the loading, off-loading and display points were observed. Consumers perceived retailer class as one of the factors influencing meat quality, but according to the instrumental measurements retailer class did not have a significant effect on physico-chemical meat quality. However, distance and storage duration significantly (p<0.05) affected (L*) and (a*) values in the meat during distribution chain. Vacuum and overwrapping packaging significantly affected (p<0.05) the shelf life of meat. Therefore, it was concluded that post-slaughter handling during the distribution chain affects the physico- chemical, microbiological and shelf-life of meat.

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Buriti, Flávia Carolina Alonso. "Sobremesa aerada simbiótica: desenvolvimento do produto e resistência do probiótico in vitro." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/9/9133/tde-18102016-103240/.

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O presente trabalho visou o desenvolvimento de uma sobremesa aerada simbiótica tipo musse, com baixo teor de gordura, processada com a adição da cultura probiótica de Lactobacillus acidophilus La-5, dos ingredientes prebióticos oligofrutose e inulina e de concentrado protéico de soro de leite (WPC), para ser armazenada sob refrigeração e congelamento, e a comparação do efeito desses ingredientes sobre as características do produto e a resistência in vitro do probiótico adicionado. Utilizando o delineamento experimental para misturas de três fatores e um ponto central, 7 formulações de musses de goiaba foram estudadas durante o armazenamento a 4°C, durante 28 dias, e a -18°C, durante 112 dias. As maiores populações de L. acidophilus foram alcançadas nas musses congeladas, com valores sempre superiores a 7 log UFC/g por até 12 semanas de armazenamento a -18°C. A viabilidade de L. acidophilus se mostrou satisfatória até o 28º dia nas musses refrigeradas adicionadas de WPC, com populações variando entre 7,7 e 6,2 log UFC/g. Para as demais musses, a população do probiótico chegou a reduzir, em média, até 2 log após 28 dias. L. acidophilus apresentou grande redução da viabilidade, tanto para as musses refrigeradas como para as congeladas, nos ensaios de sobrevivência às condições gastrintestinais simuladas in vitro. Nas musses refrigeradas, a substituição total ou parcial da gordura láctea por inulina resultou em melhor sobrevivência do probiótico durante o ensaio in vitro na primeira semana. Ao considerar o período completo de armazenamento, a menor redução da viabilidade de L. acidophilus ao longo dos ensaios in vitro foi observada para as musses congeladas. A substituição da gordura láctea por inulina e WPC e o congelamento resultaram em diferenças significativas nos parâmetros de textura das musses (p<0,05), não interferindo, porém, na sua aceitabilidade sensorial. Considerando as populações máximas do probiótico ao longo do armazenamento e a sua sobrevivência às condições gastrintestinais simuladas in vitro, observou-se os melhores resultados com a substituição parcial da gordura láctea adicionada no produto refrigerado por WPC, na proporção de 2 a 3% da formulação. A adição simultânea de WPC e inulina para musses armazenadas sob refrigeração e congelamento é recomendada desde que a proporção conjunta desses ingredientes não ultrapasse 2,6%, no sentido de não prejudicar a textura e as características sensoriais do produto. De modo especial para as musses congeladas, também é aconselhada a proporção de 2% de gordura láctea e 2% de inulina, para a qual foram obtidos os melhores resultados nos ensaios de sobrevivência in vitro do probiótico.
The aim of the present study was to develop a mousse-type synbiotic aerated dessert with low fat content, supplemented with the Lactobacillus acidophilus La-5 probiotic culture, the prebiotic ingredients oligofructose and inulin and whey protein concentrate (WPC), to be stored refrigerated and frozen, and to compare the effect of these ingredients on the product characteristics and the in vitro resistance of the added probiotic microorganism. Using a simplex centroid design, seven guava mousse-making trials were studied during storage at 4°C for 28 days and at -18°C for 112 days. The highest populations of L. acidophilus were achieved in frozen products, always above 7 log CFU/g at up to 12 weeks of storage at -18°C. L. acidophilus viability was satisfactory up to 28 days in the refrigerated mousses supplemented with WPC, with populations between 6.2 and 7.7 log CFU/g. For the other mousses, the populations decreased around 2 log cycles afier 28 days of refrigerated storage. Reductions in L. acidophilus survival during the in vitro assays were high both for refrigerated and frozen mousses. For the refrigerated mousses, the total or partial substitution of milk fat by inulin increased the probiotic survival during the in vitro assays in the first week. In terms of the whole storage, L. acidophilus survival decreased less during the in vitro assays for the frozen mousses. The substitution of milk fat by inulin and WPC and the frozen storage lead to significant differences in the texture of mousses (p<0.05), without affecting their sensory acceptability. Considering the maximum probiotic populations during storage and the survival under the in vitro simulated gastrointestinal conditions, the best results for the refrigerated product were obtained with the partial substitution of milk fat by WPC at 2 to 3%. The simultaneous addition of inulin and WPC is recommended. However, the total proportion of both ingredients together should not exceed 2.6%, so as to obtain a texture profile and a sensory acceptance similar to the traditional product. Particularly for frozen mousses, the mixture of 2% milk fat and 2% inulin in the formulation is also suggested, for which the best results on probiotic survival in the in vitro assays were observed.

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Veiga, Seliza Nancy Tavares da. "Qualidade microbiológica e físico-química de queijos comercializados em Portugal." Master's thesis, Universidade Técnica de Lisboa. Faculdade de Medicina Veterinária, 2012. http://hdl.handle.net/10400.5/4844.

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Dissertação de Mestrado em Segurança Alimentar
As infeções de origem alimentar têm sido a maior causa de doenças humanas nos últimos séculos. O leite e seus derivados merecem destaque na dieta humana por serem muito consumidos e pela sua facilidade de fabrico. A maioria dos queijos é produzida com leite de vaca, sendo os queijos puros de ovelha e cabra consideradas especialidades. A diferença de preço das matérias primas, indisponibilidade de leite de cabra e ovelha em determinados períodos do ano, e o preço do produto final são incentivos que podem levar os produtores a cometerem fraudes ao incorporar leite não declarado no rótulo. Tendo em conta que os consumidores prezam pela qualidade dos produtos que adquirem e pela confiança de que levam o que é especificado no rótulo, no presente trabalho procedeu-se à avaliação da qualidade microbiológica e química de 12 queijos adquiridos em supermercados da região de Lisboa e ainda de três amostras de leite. Avaliou-se ainda a autenticidade da informação presente nos rótulos relativamente ao tipo de leite utilizado para o seu fabrico. As análises microbiológicas incidiram sobre contagem de E. coli, microrganismos totais a 30°C, enterobacteriáceas, Sthaphylococcus coagulase positivos, bolores e leveduras; pesquisa de L. monocytogenes e Salmonella spp. Em relação às análises químicas, no queijo determinou-se a atividade de água (aw), pH e cloretos, enquanto no leite as análises químicas incidiram sobre a determinação do extracto seco, proteína, gordura e densidade. Para verificar a autenticidade dos rótulos relativamente ao tipo de leite especificado como ingrediente recorreu-se a provas baseados na amplificação de DNA-alvo (PCR- “Polymerase Chain Reaction”). Concluiu-se que os queijos em análise apresentavam boa qualidade microbiológica (e.g., ausência de E. coli em 1 g, L. monocytogenes em 25 g e Staphylococcus coagulase positivos em 1g) e que os parâmetros químicos se encontravam dentro do esperado; a técnica de PCR permitiu verificar a adulteração de queijos de cabra com leite de ovelha e de queijo de cabra-ovelha com leite de vaca.
ABSTRACT - Microbiological and physico-chemical quality of cheeses merchandized in Portugal - In recent centuries food-borne infections have been major causes of human disease. Milk and dairy products are of major importance in the human diet since they are consumed in large amounts and are ease to manufacture. Most cheeses are made from cow's milk, with ewe’s and goat cheeses being considered delicacies. Differences in the price of raw materials, unavailability of goat's and ewe’s milk in certain periods of the year, and the price of the final product can lead farmers to commit fraud by incorporating milk not declared on the label. Given that consumers value the quality of the products they purchase and trust the informations specified on the labels, in the present work we proceeded to evaluate the microbiological and chemical quality of 12 cheeses purchased at supermarkets in the region of Lisbon and three milk samples. We also assessed for the authenticity of the information included on the labels, regarding the type of milk used in the cheese manufacture. Microbiological analyzes focused on counting E. coli, total microorganisms at 30°C, coliforms, coagulase positive Staphylococcus, yeasts and molds; the presence of L. monocytogenes and Salmonella spp. were also evaluated. Regarding chemical analysis, we determined the cheese water activity (aw), pH and chloride content, while the milk chemical analyzes focused on the determination of dry matter, protein, fat and density. To verify the authenticity of the labels for the specified type of milk as an ingredient, molecular methods based on the amplification of target DNA (PCR "Polymerase Chain Reaction") were applied. Overall, the cheeses under analysis showed good microbiological quality (e.g., absence of E. coli in 1 g , L. monocytogenes in 25 g, and coagulase positive Staphylococcus in 1 g) and chemical parameters were within expected, PCR amplification allowed detection of product adulteration, namely goat cheese with ewe's milk and sheep-goat cheese with cow's milk.

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Huang, Yayu. "Effect of live yeast on the fermentation and microbiological physico-chemical parameters of the rumen, depending on the nature of the diet : modeling and validation in ruminant." Thesis, Toulouse, INPT, 2018. http://www.theses.fr/2018INPT0003.

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L'acidose ruminale est l'une des préoccupations majeures des exploitations laitières actuelles. Les levures vivantes (LV) ont été largement étudiées et utilisées chez les vaches laitières pour stabiliser la fermentation ruminale. Récemment, la mesure du potentiel redox ruminal (Eh, en mV) a été considérée comme un outil intéressant pour indiquer le trouble de la fermentation ruminale. L'effet positif de LV sur Eh ruminal a été rapporté, mais il reste variable selon les conditions expérimentales. Les objectifs de ce travail étaient de fournir une meilleure compréhension du mode d'action de LV et de définir la condition optimale de l'utilisation de LV chez les vaches laitières. La première partie de ce travail a consisté en une analyse quantitative des résultats de 22 expériences avec des vaches laitières canulées. La deuxième partie de ce travail a consisté à vérifier certains des résultats de l'analyse quantitative par une expérience chez des vaches en lactation. En utilisant l'analyse quantitative de données existantes provenant d'expériences antérieures, nous avons clarifié la relation entre le Eh ruminal et d'autres paramètres ruminaux principaux tels que le pH et le profil VFA, et suggéré que les variations de Eh pourraient être liées au transfert d'électrons dans les réactions dans le rumen. En outre, la réponse du Eh après la supplémentation en LV était également liée à celle du profil AGV ruminal, suggérant que l'effet de LV sur le profil VFA était atteint par l'augmentation du pouvoir réducteur, reflétant un meilleur transfert d'électrons dans le rumen. L'analyse a en outre démontré que la régulation du Eh ruminal par LV serait particulièrement efficace lorsque le risque de troubles digestifs est élevé. Puisque l'influence des caractéristiques de la ration sur le Eh ruminal a été quantifiée, l'effet de LV dans un régime donné pourrait être estimé indirectement. En outre, l'analyse quantitative a également révélé que la réponse de Eh suite à la supplémentation en LV était associée à la quantité de sucres solubles ingérée. L'expérience in vivo chez des vaches en début de lactation a confirmé un effet plus important de LV sur Eh ruminal avec une ration riche en sucres solubles, et a démontré que la supplémentation en LV avait un impact sur la richesse des bactéries, et que les métabolites ont également été influencés par la supplémentation en LV, probablement associée à la diminution du Eh ruminal
Ruminal acidosis is one of the major concerns of current dairy farms. Live yeasts (LY) have been extensively studied and used in dairy cows for stabilization of rumen fermentation. Recently, measurement of ruminal redox potential (Eh, in mV) has been considered as an interesting tool to indicate ruminal fermentation disorder. The positive effect of LY on ruminal Eh has been reported, but it remains variable according to the experimental conditions. The aims of this work was to provide better understanding of mode of actions of LY, and to define the optimal condition of LY utilization in dairy cows. The first part of this work consisted to quantitative analysis of existing results from 22 experiments with cannulated dairy cattle. The second part of this work consisted to verify some of the results from quantitative analysis by an in vivo experiment in lactating cows. By using quantitative analysis of existing data from previously conducted experiments, we clarified the relationship between ruminal redox and other main ruminal parameters such as pH and VFA profile, and suggested that Eh variations might be related to the transfer of electrons in the reactions producing VFAs in the rumen. Moreover, response of ruminal Eh following live yeast supplementation was also related to that of ruminal VFA profile, which suggested that the effect of LY on VFA profile was achieved via the increase of reducing power, possibly reflected improved electron transfer and use in the rumen. The analysis further demonstrated that the regulation of ruminal Eh by LY would be particularly effective when risk of digestive disorder is high. Since the influence of dietary characteristics on ruminal Eh was quantified, the effect of LY in a given diet could be indirectly estimated. In addition, quantitative analysis also associated the response of ruminal Eh following LY supplementation to the intake of soluble sugars. The in vivo experiment in early-lactating cows confirmed greater effect of LY on ruminal Eh in diet rich in soluble sugars, and further demonstrated that i) LY supplementation tended to impact the richness of ruminal bacteria, and ii) some unidentified metabolites were also influenced by LY supplementation, probably associated to the decrease of ruminal Eh

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Al-Awad, Musaed Naser J. "Physico-chemical analysis of shale-drilling fluid interaction and its application in borehole stability studies." Thesis, Heriot-Watt University, 1994. http://hdl.handle.net/10399/1368.

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Shale is often the most difficult of all formations to maintain a stable wellbore in when drillincr ::> for oil and gas. Time and money spent overcoming this problem during drilling, together with overall reduced profit margins. has led the oil industry to devote considerable time and effort to solve the problem of unstable boreholes in shales. It has long been established that the moisture adsorption (or desorption) of shale rocks can be controlled by the salinity of drilling fluid. When compacted shale (under constant compaction stress) adsorbs moisture, its total volume increases and swelling strains develop. Developed swelling strains then become an integral part of the effective radial stress acting on the shale formation contributing to borehole failure. A mathematical model has been developed for predicting the swelling behaviour of shale when placed in contact with water under moderate pressures and the effect of the swelling on borehole (in)stability. The model is based on thermodynamic theory which suggests that fluid movement into or out of a shale is driven by an imbalance in the partial molar free energy of the shale and the contacting fluid. Conversion of the free energy of each system (fluid and shale) into "total swelling pressure" made it possible to model transient pressures and strains generated in shale. The analytical solution of the radial diffusivity equation is reduced to a simpler form for the model. The model was validated using equipment and experimental techniques which allow continuous monitoring of shale swelling as function of time and distance from the wetting end. It was found that increasing the compaction stress acting on the shale reduced the rate of swelling, and increasing the hydraulic pressure of the fluid on the shale's wetted surface increased the rate of swelling. This behaviour was adequately described by the model which therefore represents a new method for predicting shale swelling as function of time and radial distance under different environments. Swelling strains are then used to predict related changes in shale mechanical properties (failure criteria) and well (in)stability. Several well-site index tests have been developed to study shale-drilling fluid interaction at wellsite. These index tests can provide input data for the mathematical model. Drilling fluids can be screened for their ability to control shale swelling, thus minimising the risk of well bore instability.

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Alves, Lúcia Maria Coêlho [UNESP]. "Qualidade da água de múltiplos usos na microrregião de Itapecuru-Mirim-MA." Universidade Estadual Paulista (UNESP), 2010. http://hdl.handle.net/11449/103810.

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Made available in DSpace on 2014-06-11T19:32:52Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-06-07Bitstream added on 2014-06-13T19:03:31Z : No. of bitstreams: 1 alves_lmc_dr_jabo.pdf: 5616819 bytes, checksum: 4a53256d90bbcf403f575125bc5a14c7 (MD5)
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A água é um recurso natural indispensável à vida, é essencial à promoção social, à produção de alimentos e ao desenvolvimento econômico. Com o objetivo de se avaliar a qualidade microbiológica e físico-química de águas subterrâneas e superficiais na microrregião de Itapecuru-Mirim-MA foram colhidas 172 amostras de água, sendo 86 no período chuvoso (março a maio) e 86 amostras no período de estiagem (agosto a outubro). Destas, 39 amostras eram águas consumidas em residências rurais procedentes de poços artesianos, poços rasos, fontes naturais e Rede Publica de Abastecimento, 05 eram de uso doméstico, 08 de lavagem dos tetos das vacas; 02 de uso em laticínios, 01 de uso em matadouro, 01 de fábrica de polpas de frutas, 18 de bebedouros dos animais, 09 águas de uso em piscicultura e 03 de irrigação de hortaliças. Foram analisados parâmetros microbiológicos e físico-químicos e aplicado um questionário fechado contendo perguntas objetivas para se avaliar o nível de conhecimento das pessoas quanto à qualidade da água usada ou consumida e mapeado geograficamente os pontos de colheitas. Os resultados das análises microbiológicas e físico-químicas identificaram 52 (66,66 %) amostras de água de consumo humano em desacordo com os padrões microbiológicos e 23 (29,48%) em desacordo com os parâmetros físico-químicos, nove (90%) amostras de água de uso doméstico não atenderam aos padrões microbiológicos, enquanto seis (60%) não o foram para os padrões físico-químicos, para água de lavagem dos tetos evidenciaramse 13 (81,25%) e 10 (62,50%) amostras, respectivamente, fora dos padrões microbiológicos e físico-químicos vigentes. Não foi constatada contaminação microbiológica nem físico-química para água de uso em laticínio e em fábrica de polpa de frutas. Referente à água de uso em matadouro, uma (50%) amostra não atendeu aos padrões...
Water is a natural resource essential for life, it is essential to social promotion, food production and economic development. In order to evaluate the microbiological and physical chemistry quality of groundwater and surface water in the municipality of Itapecuru-Mirim-MA were collected 172 water samples, including 86 in the rainy season (March-May) and 86 samples in the dry weather period (August- October). From these total, 39 samples were water consumed in rural residences coming from shallow water wells, artesian water wells, natural sources and public water supply, 05 were domestic water, 08 from teat washings of cows; 02 for use in dairy products, 01 from the slaughterhouse, 01 from a factory fruit pulps, 18 from animal drinking fountains, 09 water samples used for pisciculture and 03 from vegetables irrigation. They were all analyzed for the microbiological and physical-chemical parameters. A close questionnaire with objective questions was also applied to evaluate the awareness level of people about the water quality used or consumed and the crops points were geographically mapped. The microbiological and physical-chemical results identified 52 (66,66%) water samples for human consumption in discordance with the microbiological standards and 23 (29,48%) in discord to the physical-chemical parameters, nine (90%) water samples for domestic use did not attend to the microbiological standards, while six (60%) were not for the physical-chemical parameters. The teat washing water results showed that 13 (81,25%) and 10 (62,50%) samples, respectively, were out of the microbiological and physical-chemical actual patterns. It was not detected microbiological contamination of water used in the dairy and in the fruit pulp factory. Referring to the water used in the slaughterhouse, one (50%) sample did not attend to the microbiological patterns, but all samples attended to the physical-chemical...(Complete abstract click electronic access below)

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Castro, Adriano Perrelli Pestana de. "Avaliação das condições higienicossanitárias e análise de parâmetros microbiológicos e físico-químicos do pescado importado no Porto de Santos/SP." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/10/10134/tde-02062017-093929/.

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Introdução - O pescado é amplamente utilizado para a produção de alimentos à base de matéria-prima de origem animal. A importação de pescado vem crescendo ano a ano, sendo o Porto de Santos/SP uma das principais rotas de entrada desse produto no país. Objetivos - Avaliar as condições higienicossanitárias de pescado importado no Porto de Santos/SP. Métodos - A pesquisa foi desenvolvida com base em duas abordagens: estudo dos requisitos obrigatórios para nacionalização do produto importado com base na legislacão vigente e trabalho desempenhado pelo Vigiagro/MAPA, assim como, estudo laboratorial. Foram coletadas 60 amostras de 30 diferentes produtos de pescado sendo cada amostra constituída por, no mínimo, 500 g do produto de uma mesma marca, lote, data de fabricação e validade. Uma parte das amostras, 30 embalagens de 500 g no mínimo, foi acondicionada em caixas isotérmicas com temperatura controlada e encaminhada para realização das análises microbiológicas. As demais 30 embalagens foram encaminhadas, sob as mesmas condições, para realização das análises físico-químicas. As análises físico-químicas e microbiológicas foram realizadas em Laboratórios credenciados no Mapa. Para produtos congelados foram realizadas as análises microbiológicas para pesquisa de Salmonella spp em 25 gramas e contagem de Staphylococcus coagulase positiva e realização das análises físico-químicas de N-BVT. Para produtos salgados refrigerados, foram realizadas análises microbiológicas para pesquisa de Salmonella spp em 25 gramas, contagem de Staphylococcus coagulase positiva e contagem de coliformes termotolerantes a 450 C, assim como, realização das análises físico-químicas de umidade e resíduo mineral fixo. Resultados - Nos produtos congelados, as análises físico-químicas para o N-BVT e as análises microbiológicas para pesquisa de Salmonella spp em 25 gramas e contagem de Staphylococcus coagulase positiva indicaram 100,0% de conformidade com a legislação vigente. Nos produtos salgados refrigerados, as análises microbiológicas para pesquisa de Salmonella spp em 25 gramas, contagem de Staphylococcus coagulase positiva e contagem de coliformes termotolerantes a 450 C também indicaram 100,0% de conformidade com a legislação vigente. Por outro lado, 100,0% das análises físico-química de umidade e 44,4% das análises físico-químicas para resíduo mineral fixo no pescado salgado resfriado estavam com valores acima da legislação vigente. Todos os produtos apresentaram documentação obrigatória e rótulo de acordo com a legislação vigente. Conclusão Embora os resultados das análises microbiológicas tenham demonstrado que os produtos estivessem próprios para o consumo, as análises físico-químicas, em específico os parâmetros referentes a umidade no pescado salgado refrigerado, não estavam de acordo com os valores determinados pela legislação vigente. A legislação sanitária vigente para importação de pescados, assim como a metodologia de inspeção e fiscalização desses produtos, se mostrou eficiente comparado aos resultados laboratoriais encontrados, com possibilidade de inclusão de novas ferramentas e análises laboratoriais visando garantir, ainda mais, as condições higiênicossanitárias e segurança alimentar.
Introduction - Seafood is widely used for the production of food based on raw materials of animal origin. The fish import has been growing year by year, and the Port of Santos / SP one of the main routes of entry of that product in the country. Objectives - To evaluate the hygienic-sanitary conditions of imported fish in the Port of Santos / SP. Methodology - The study was based up on two approaches: study of the mandatory requirements for nationalization of the imported product on the basis of current legislation and work performed by Vigiagro / MAPA, as well as laboratory study. It was collected 60 samples from 30 different products of fish each sample being composed by 500 g from the same brand, batch number, manufacturing and expiration date. A share of these samples, 30 packages of 500 g at least, was accommodated and transported in temperature-controlled isothermal box to the microbiological analysis. The remaining 30 packages were sent, under the same conditions, to physico-chemical analysis. The physico-chemical and microbiological analyzes were performed in laboratories accredited on MAPA. For frozen products were performed microbiological analyzes for Salmonella spp research in 25 g Staphylococcus and count coagulase positive and achievement of physical and chemical analysis of N-BVT. For salted products, microbiological analyzes were performed for detection of Salmonella spp in 25 g, Staphylococcus coagulase positive count and count of coliform to 450 C and physical-chemical analysis for humidity and fixed mineral residue. Results - In the frozen products, physico-chemical analysis for the N-BVT and microbiological analyzes for Salmonella spp research in 25 g and Staphylococcus coagulase positive counts indicated 100.0% of compliance with current regulation. In salted products, microbiological analyzes for Salmonella spp research in 25 g, Staphylococcus coagulase positive and coliform to 450 C counts also indicated 100.0% compliance with current legislation. On the other, 100.0% of the physico-chemical analysis of humidity and 44,4 % in the ashs physico-chemical results, in salted fish, were with higer limits established by Brazilian legislation. All products submitted mandatory documents required for import and labeling in accordance with current regulation. Conclusion - Although the results of the microbiological analyzes showed that the imported fish were apropriate for consumption, the physico-chemical analysis, in particularly the humidity parameters were not in accordance with values indicated in the current regulation. The current health regulation for the imported fish, as well as the inspection methodology and supervision of these products, was efficient compared to laboratory findings, with the possibility of adding new tools and laboratory tests to ensure even more the higienic-sanitary conditions and food safety.

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Holderer, Olaf-Notker. "Nano-structural and physico-chemical analysis of Pd-Sn colloidal solutions applied to the metallisation of polymers." Lyon, INSA, 2002. http://theses.insa-lyon.fr/publication/2002ISAL0023/these.pdf.

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Le revêtement électrochimique de métaux sur des polymères est fréquemment réalisé dans de nombreuses applications industrielles. La surface du polymère doit pour cela subir un traitement d'activation. Dans une première étape, une fine couche de colloi͏̈des palladium-étain est déposée sur le polymère ; elle est suivie d'une étape d'échange qui consiste à échanger des atomes d'étain par des atomes de cuivre pour accroître la conductivité de surface et rendre alors possible l'électrodéposition d'un métal comme le cuivre par exemple. Les colloi͏̈des déposés sont produits dans une suspension acide. Leur taille est voisine de 2 nm et ils sont supposés avoir un cœur constitué d'un alliage Pd-Sn entouré d'une peau riche en étain. Le but de notre étude est d'approfondir la nature physico-chimique des suspensions colloi͏̈dales et des couches adsorbées en surface d'un polymère en combinant plusieurs techniques de caractérisation microstructurales fines comme la diffusion centrale de rayons X (SAXS), la cryo-microscopie électronique, la microscopie électronique à haute résolution (METHR), la spectroscopie de rayons X (EDX) et photoélectrons (XPS), la rétrodiffusion (RBS) et la spectroscopie de pertes d'énergie des électrons transmis (EELS). Les deux premières techniques ont donné des informations sur la valeur et la distribution des tailles des colloi͏̈des ainsi que sur la stabilité des solutions. La nature cristallographique des colloi͏̈des a été appréhendée par METHR tandis que la composition chimique à l'échelle atomique a été obtenue par EELS en mode nano-sonde. C'est ainsi que nous avons validé un enrichissement superficiel en étain des colloi͏̈des. Les analyses des couches déposées en surface des polymères après chacune des étapes du procédé de métallisation, ont permis d'appréhender l'évolution de la nano-structure et de la chimie des couches colloi͏̈dales au cours de leur élaboration
Electrochemical deposition of metals on polymer substrates is a widely used industrial application, for example in surface finishing. The polymer surface requires a pre-treatment in order to get activated. In a first step, a thin layer of palladium-tin nano-colloids is deposited on the surface, followed by a Cu-Sn exchange step, which enhances the conductivity and enables the electrodeposition of metals like Cu. The colloids deposited in the first step from an acid suspension are supposed to have a core, which consists of a Pd-Sn alloy and a stabilising shell of tin. The size of the colloids is ~2 nm. Aim of this study is to get a deeper insight into the nature of the colloidal suspension and the adsorbed surface layers by combining different experimental techniques for a chemical and structural analysis at the nanometer scale, such as small angle X-ray scattering (SAXS), X-ray photoelectron spectroscopy (XPS), Cryo-electron microscopy (Cryo-TEM), high resolution transmission electron microscopy (HRTEM), Rutherford Back-Scattering (RBS) and electron energy loss spectroscopy (EELS). The colloidal solution has been characterised by SAXS and Cryo-TEM, which allowed to determine the size of the colloids and to obtain information on the stability of the solution. The crystallographic structure of the colloids in suspension has been studied with HRTEM. EELS has been used to study the chemical composition of the colloids. By focussing the electron beam to sub-nanometric spot sizes it has been possible to get very local information on the elemental composition of the colloids and to evidence a slight Sn surface enrichment. The analysis of the surface layer after each of the different steps of the plating process allowed determining the nano-structure and chemistry of the adsorbed colloidal layer and its modification during the process

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Siegwein, Alexander Martin. "THE EFFECTS OF SOY PROTEIN ISOLATE ADDITION ON THE PHYSICO-CHEMICAL PROPERTIES OF GUMMI CONFECTIONS." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1276883276.

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Privatti, Rafaela Torrezan. "Efeitos da contagem bacteriana total do leite cru refrigerado sobre os parâmetros físico-químicos, microbiológicos e rendimento durante a vida útil do queijo Minas Frescal." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/74/74131/tde-23112017-101955/.

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A Contagem Bacteriana Total (CBT) é um critério de avaliação da qualidade higiênico-sanitária do leite. O presente estudo teve por finalidade avaliar o efeito da CBT do leite cru refrigerado, sobre as características físico-químicas, microbiológicas e rendimento do queijo Minas Frescal. Utilizaram-se leites com dois níveis de CBT para a fabricação dos queijos: baixa CBT= média de 18.400 UFC/mL e alta CBT= média de 74.100 UFC/mL. As etapas de elaboração dos queijos incluíram a pasteurização do leite, adição dos ingredientes (cloreto de cálcio, cloreto de sódio e coalho), coagulação e obtenção do coágulo, dessoragem, enformagem e embalagem. Os queijos foram embalados em embalagens plásticas e analisados nos dias 1, 7, 14 e 21 após a fabricação e durante esse período foram mantidos em câmara fria a 6°C. A sequência de elaboração dos queijos foi repetida 3 vezes, para cada nível de CBT, totalizando 60 unidades por tratamento. Cinco unidades de queijos foram analisadas por dia, os parâmetros físico-químicos avaliados foram: teores de umidade, proteína e gordura, índices de extensão e profundidade da proteólise, pH, acidez titulável e extensão da lipólise, e os microbiológicos: coliformes termotolerantes, estafilococos coagulase positiva, Salmonella spp. e Listeria monocytogenes. Utilizou-se um delineamento experimental em parcelas subdivididas em blocos, considerando-se a contagem bacteriana total como efeito principal, os dias de análise como subparcelas e os processamentos como blocos. Nos queijos Minas Frescal não houve interação dos níveis de CBT e período de armazenamentos para os teores de umidade, proteína, gordura e índices de extensão e profundidade da proteólise. Entretanto, houve efeito dos níveis de CBT para as porcentagens médias de proteína e índices de extensão e profundidade da proteólise, com valores superiores para o tratamento com alta CBT, para o teor de umidade houve efeito dos níveis de CBT, com médias de 63,46% e 60,77% para os tratamentos com baixa e alta CBT, respectivamente. Independentemente dos níveis de CBT, houve efeito do período de armazenamento, com decréscimo no teor médio de umidade e elevação nos teores médios de gordura, proteína e índice de extensão da proteólise. Para as características de pH e acidez titulável houve interação para os níveis de CBT e período de armazenamento, a partir do 14° dia. O pH do tratamento com baixa CBT apresentou variação discreta (6,59-6,49), enquanto que para o tratamento com alta CBT houve decréscimo de 6,72 para 6,15, o aumento de acidez foi verificado em ambos os tratamentos, porém em maior grau no grupo de alta CBT. A extensão da lipólise apresentou interação para os níveis de CBT e período de armazenamento, no 21° dia após a fabricação, com aumento no teor de ácidos graxos livres. Salmonella spp. e Listeria monocytogenes não foram encontradas nos queijos, 5,2% das amostras apresentaram coliformes termotolerantes, porém em contagem permitida pela legislação brasileira. No entanto, no 14° dia após a fabricação, 9,56% das amostras apresentaram estafilococos coagulase positiva, em contagens superiores aos padrões legais. O rendimento dos queijos Minas Frescal não sofreu influência dos níveis de CBT. Os resultados do trabalho indicaram que os queijos Minas Frescal produzidos com leites contendo CBT inferior a 50.000 UFC/mL, originam produtos mais estáveis e de melhor qualidade ao longo do período de armazenamento.
The Total Bacterial Count (TBC) is a criterion for the evaluation of hygienic-sanitary quality of milk. The present study had the purpose of evaluating the effect of TBC of the refrigerated raw milk, on the physical-chemical characteristics, microbiological and yield of the Minas Frescal cheese. Milks with two levels of TBC were used for cheese production: low TBC= mean of 18400 CFU/mL and high TBC= mean of 74100 CFU/mL. The manufacture of cheeses included: pasteurization of the milk, addition of ingredients (calcium chloride, sodium chloride and rennet), coagulation, mass cutting, desorption, forming and packaging. The cheeses were packed in plastic bags and analyzed on days 1, 7, 14 and 21 after manufacture and during that period were kept in a cold chamber at 6°C. The sequence of elaboration of the Minas cheeses were repeated 3 times, for each level of TBC, totaling 60 units per treatment. Five cheese units were analyzed per day, the physical-chemical parameters evaluated were: percentages of fat, humidity, protein, extension and depth of proteolysis, pH, titratable acidity and extent of lipolysis, and the micro-organisms evaluated were: thermotolerant coliforms, coagulase-positive staphylococci, Salmonella spp. and Listeria monocytogenes. A completely randomized block design was used, considering TBC as the main effect, the days of analysis as sub parcels and the processing batches as the blocks. In the Minas Fresch cheese there weren\'t interaction for TBC levels and storage period for humidity, protein, fat contents and extension and depth of proteolysis. However, there were effect for TBC levels and protein percentages and extension and depth of proteolysis, with higher values for treatment with low TBC, for moisture content there was effect for TBC levels, with averages of 63.46% and 60.77% for treatments low and high TBC, respectively. Regardless of TBC levels, there were effect for the storage period, with decreases in the moisture content and elevation in the protein, fat contents and proteolysis extension index. For the characteristics pH and titratable acidity there were interaction for TBC levels and storage period, on day 14, for pH the treatment with low TBC did not present expressive variation (6.59-6.49), while the treatment high TBC presented a decrease from 6.72 to 6.15, the increase of acidity was observed in both treatments, but to a greater extent in the high TBC group. The extent of lipolysis showed interaction for TBC levels and storage period, on day 21, with elevation of content of free fatty acids. Salmonella spp. and Listeria monocytogenes were not found in the cheeses. 5.2% of the samples presented thermotolerant coliforms but in count allowed by the Brazilian legislation. However on the 14th day after the manufacture, 9.56% of the samples presented coagulase-positive staphylococci in scores above legal standards. The yield of the Minas Frescal cheeses was not influenced by TBC levels. The results of the study indicated that Minas Frescal cheeses produced with milks containing TBC of less than 50.000 CFU/mL produce more stable and better quality products throughout the storage period.

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Porkert, Sebastian. "Physico-Chemical Processes during Reactive Paper Sizing with Alkenyl Succinic Anhydride (ASA)." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-219620.

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Sizing (hydrophobization) is one of the most important process steps within the added-value chain of about 1/3rd of the worldwide produced paper & board products. Even though sizing with so-called reactive sizing agents, such as alkenyl succinic anhydride (ASA) was implemented in the paper industry decades ago, there is no total clarity yet about the detailed chemical and physical mechanisms that lead to their performance. Previous research was carried out on the role of different factors influencing the sizing performance, such as bonding between ASA and cellulose, ASA hydrolysis, size revision as well as the most important interactions with stock components, process parameters and additives during the paper making process. However, it was not yet possible to develop a holistic model for the explanation of the sizing performance given in real life application. This thesis describes a novel physico-chemical approach to this problem by including results from previous research and combining these with a wide field of own basic research and a newly developed method that allows tracing back the actual localization of ASA within the sheet structure. The carried out measurements and trial sets for the basic field of research served to evaluate the stock and process parameters that most dominantly influence the sizing performance of ASA. Interactions with additives other than retention aids were not taken into account. The results show that parameters, such as the content of secondary fibers, the degree of refining, the water hardness as well as the suspension conductivity, are of highest significance. The sample sets of the trials with the major impacting parameters were additionally analyzed by a newly developed localization method in order to better understand the main influencing factors. This method is based on optical localization of ASA within the sheet structure by confocal white light microscopy. In order to fulfill the requirements at magnification rates of factor 100 optical zoom, it was necessary to improve the contrast between ASA and cellulose. Therefore, ASA was pretreated with an inert red diazo dye, which does not have any impact on neither the sizing nor the handling properties of ASA. Laboratory hand sheets that were sized with dyed ASA, were analyzed by means of their sizing performance in correlation to measurable ASA agglomerations in the sheet structure. The sizing performance was measured by ultrasonic penetration analysis. The agglomeration behavior of ASA was analyzed automatically by multiple random imaging of a sample area of approx. 8650 µm² with a minimum resolution for particles of 500 nm in size. The gained results were interpreted by full factorial design of experiments (DOE). The trials were carried out with ASA dosages between 0% and 0.8% on laboratory hand sheets, made of 80% bleached eucalyptus short fiber kraft pulp and 20% northern bleached softwood kraft pulp, beaten to SR° 30, produced with a RDA sheet former at a base weight of 100 g/m² oven dry. The results show that there is a defined correlation between the ASA dosage, the sizing performance and the number and area of ASA agglomerates to be found in the sheet structure. It was also possible to show that the agglomeration behavior is highly influenced by external factors like furnish composition and process parameters. This enables a new approach to the explanation of sizing performance, by making it possible to not only examine the performance of the sizing agent, but to closely look at the predominant position where it is located in the sheet structure. These results lead to the explanation that the phenomenon of sizing is by far not a pure chemical process but rather a more physical one. Based on the gained findings it was possible so far to optimize the ASA sizing process in industrial-scale by means of ~ 50% less ASA consumption at a steady degree of sizing and improved physical sheet properties.

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Apreutesei, Mihai. "Temperature impact on thermal evolution of advanced PVD ceramic and metallic glass thin films : Physico-chemical and microstructural analysis." Thesis, Lyon, INSA, 2015. http://www.theses.fr/2015ISAL0009/document.

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Ces dernières années, les exigences de l'industrie dans le développement de nouveaux matériaux fonctionnels en mesure de résister aux conditions difficiles pendant l'opération d'usinage sont en constante augmentation. Les chercheurs doivent donc trouver de nouvelles solutions pour répondre aux besoins industriels de plus en plus sévères. L’utilisation de revêtement protecteur à la surface de l’outil de coupe est une solution très efficace. Des nouveaux matériaux architecturés sont étudiés pour leurs propriétés mécaniques, physiques et chimiques uniques assurant une résistance aux dégradations de surface dues à la corrosion, l'usure, le frottement; en particulier lorsque ces outils sont utilisés dans des environnements hostiles. Dans le cadre de cette thèse de doctorat, l'influence de la température sur la stabilité structurale de deux types de films minces déposés par PVD a été étudiée. Des films céramiques et de verre métallique ont été envisagés. Afin de préparer et optimiser ces films, le projet s’est axé sur l'étude de l'influence des conditions de dépôt sur les caractéristiques de croissance du film: composition chimique, structure, morphologie, puis sur les changements ultérieurs des principales propriétés des films minces, à savoir la résistance à l’oxydation et à la cristallisation lors de leur utilisation à hautes températures. Une démarche multi-échelle a été développée pour caractériser au mieux les couches. La première partie du travail est liée aux revêtements céramiques à base de CrN pour donner de nouvelles fonctionnalités et améliorer la surface des outils de coupe dans le but essentiel d'accroître leur durée de vie. La seconde partie du manuscrit est dédiée aux films minces de verres métalliques de Zr-Cu préparés par un procédé de co-pulvérisation magnétron PVD. Le but de cette partie consiste en l’étude de la relation entre la structure amorphe de ces films et leurs propriétés mécaniques. La conservation du caractère amorphe de ces films en température présente également un caractère essentiel. Les verres métalliques ont récemment attiré un fort intérêt car ils présentent des propriétés mécaniques intéressantes à température ambiante. Ils présentent, de ce fait, un grand potentiel pour des applications d'ingénierie en raison de leurs caractéristiques mécaniques et physico-chimiques uniques (haute limite élastique, résistance à la corrosion ...). Pour relier les propriétés mécaniques des couches à l’évolution de leurs microstructures, une partie importante de ce travail a porté sur l’observation de l’évolution de la couche au cours du chauffage au moyen de techniques de caractérisation in situ. Les films minces proposés au cours de ce travail peuvent être envisagées pour un large gamme d’application dans l’ingénierie de surface pour protéger les surfaces et améliorer la durée de vie des matériaux
In the recent years the industrial requirements to develop new functional materials able to overcome the severe conditions during machining operation are continuously increasing. Researchers then must find novel solutions to respond to their severe industrial requirements. To coat the tool surface with advanced coatings is the most efficient solution. New nanostructured materials may nowadays exhibit unique mechanical, physical and chemical properties ensuring notable degradation resistance where the surface protection of materials against corrosion, wear, friction or oxidation is a key issue, particularly when operating in hostile environments. Within the scope of this Ph.D. thesis the influence of the temperature on the structural stability of two different PVD ceramic and metallic glass thin films is proposed. The main goal consists in the development of two distinct classes of thin films, with a wide range of properties. In order to prepare these films, the project will be focused on the study on the influence of PVD deposition conditions in the particular film’s growth characteristics: chemical composition, structure, morphology and the subsequent changes in the main properties of the thin films, namely oxidation and crystallization resistance, especially. For that purpose we adopted the multiscale approach. The first part is related to the ceramic CrN-based coatings to give new functionalities and improve the tools’ surface with the primary aim to increase their lifetime. Secondly, new protective materials able to better protect the exposed surfaces against high temperature oxidation have been proposed, namely CrAlN and CrAlYN coatings as will be evidenced in this manuscript. The second part of the manuscript is dedicated to the innovative Zr-Cu thin films metallic glasses prepared by a PVD magnetron co-sputtering method with the objective to investigate the amorphization ability and their structural properties. Their excellent properties at room temperature have recently attracted attention as a new class of materials with great potential for engineering applications due to unique mechanical and physico-chemical characteristics (high elastic strain limit, corrosion resistance…). Finally, an important approach during the course of this thesis was the real time observation of the structure and surface modifications during heating by means of in situ methods. The thin films proposed during the course of the work could be straightforward used as surface engineering solutions to protect and extend the lifetime of the materials and components

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Canale, Ivan 1977. "Caracterização microbiológica, parasitológica e físico-química da água de lavagem de filtros recirculada em ETA de ciclo completo = Microbiological, parasitological and physico-chemical characterization of filter backwash water recirculated in full cycle WTP." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/267710.

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Orientador: Cassiana Maria Reganhan-Coneglian
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Tecnologia
Made available in DSpace on 2018-08-26T04:53:56Z (GMT). No. of bitstreams: 1 Canale_Ivan_M.pdf: 7288933 bytes, checksum: 93678fbce9055e79b05000fd1cab8c23 (MD5) Previous issue date: 2014
Resumo: Estações de Tratamento de Água (ETA) de ciclo completo. Como o volume de ALF pode representar de 3 a 6% do volume de água tratada produzido na ETA, existe interesse cada vez maior no tratamento desse efluente para fins de recirculação junto com a água bruta aduzida à ETA. Entretanto, existe uma preocupação de que essa água residuária possa conter matéria orgânica, sólidos totais, metais, carbono orgânico, precursores de trihalometanos, cistos/oocistos de protozoários ou outras impurezas concentradas durante o processo de filtração. Este trabalho de pesquisa tem como objetivo caracterizar com base em parâmetros físico-químicos, microbiológicos e parasitológicos a água de lavagem de filtros gerada e recirculada na ETA Capim Fino, em Piracicaba / SP - Brasil. Foram avaliadas 12 amostras da água bruta do manancial que abastece a ETA (rio Corumbataí), ALF bruta, ALF clarificada (com o uso de polímeros auxiliares ou por simples sedimentação) e água filtrada da ETA. Para caracterização da ALF foram analisados os parâmetros físico-químicos: cloro residual, cor, turbidez, pH, alumínio solúvel, sólidos totais fixos, sólidos totais voláteis, sólidos sedimentáveis, carbono orgânico total e o potencial de formação de trihalometanos; os parâmetros microbiológicos: coliformes totais, Escherichia coli; e os protozoários patogênicos: Giardia spp. e Cryptosporidium spp. O monitoramento da ALF bruta apontou como principais características físico-químicas deste efluente elevados teores de turbidez, alumínio, carbono orgânico total, sólidos totais (fixos e voláteis), sólidos sedimentáveis e potencial de formação de THM. A clarificação da ALF com polímero aniônico possibilitou a redução na concentração dos diversos constituintes analisados. Giardia spp. foi detectada na água bruta (cinco resultados positivos e concentração de cistos variando de Abstract: Filter backwash water (FBWW) is the largest liquid waste generated in a conventional water treatment plant (WTP). As the volume of FBWW can represent from 3 to 6% of the volume of treated water produced in the WTP, there is an increasing interest in treatment and recycling of this effluent with raw water adducted to WTP. But FBWW would contain concentrated organic matter, total solids, metals, organic carbon, trihalomethanes (THM) precursors, cysts/oocysts of protozoa and other impurities which could be a concern. This research aims to characterize FBWW generated and recirculated in Capim Fino WTP in Piracicaba / SP - Brazil by physico-chemical, microbiological and parasitological analyses. Twelve samples of raw water from the river that supplies the WTP (Corumbataí river), raw FBWW, clarified FBWW (using auxiliary polymers or simple sedimentation) and filtered water were collected and evaluated. The physico-chemical parameters were: residual chlorine, color, turbidity, pH, soluble aluminum, total fixed and volatile solids, settleable solids, total organic carbon and THM potential formation; microbiological parameters: total coliforms and Escherichia coli; and pathogenic protozoa Giardia spp. and Cryptosporidium spp. Monitoring the raw FBWW pointed as the main physicochemical characteristics high levels of turbidity, aluminum, total organic carbon, total solids (fixed and volatile), sedimentary solids and THM potential formation. Clarification of FBWW with anionic polymer resulted in a reduction in the concentration of the various parameters. Giardia spp. was found in raw water (five positive results and cyst concentration ranging from Mestrado
Tecnologia e Inovação
Mestre em Tecnologia

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Alves, Lúcia Maria Coêlho. "Qualidade da água de múltiplos usos na microrregião de Itapecuru-Mirim-MA /." Jaboticabal : [s.n.], 2010. http://hdl.handle.net/11449/103810.

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Orientador: Luiz Augusto do Amaral
Banca: Antonella Cristina Bliska Jacinto
Banca: Francisca Neide Costa
Banca: Maria da Glória Buzinaro
Banca: Oswaldo Durival Rossi Junior
Resumo: A água é um recurso natural indispensável à vida, é essencial à promoção social, à produção de alimentos e ao desenvolvimento econômico. Com o objetivo de se avaliar a qualidade microbiológica e físico-química de águas subterrâneas e superficiais na microrregião de Itapecuru-Mirim-MA foram colhidas 172 amostras de água, sendo 86 no período chuvoso (março a maio) e 86 amostras no período de estiagem (agosto a outubro). Destas, 39 amostras eram águas consumidas em residências rurais procedentes de poços artesianos, poços rasos, fontes naturais e Rede Publica de Abastecimento, 05 eram de uso doméstico, 08 de lavagem dos tetos das vacas; 02 de uso em laticínios, 01 de uso em matadouro, 01 de fábrica de polpas de frutas, 18 de bebedouros dos animais, 09 águas de uso em piscicultura e 03 de irrigação de hortaliças. Foram analisados parâmetros microbiológicos e físico-químicos e aplicado um questionário fechado contendo perguntas objetivas para se avaliar o nível de conhecimento das pessoas quanto à qualidade da água usada ou consumida e mapeado geograficamente os pontos de colheitas. Os resultados das análises microbiológicas e físico-químicas identificaram 52 (66,66 %) amostras de água de consumo humano em desacordo com os padrões microbiológicos e 23 (29,48%) em desacordo com os parâmetros físico-químicos, nove (90%) amostras de água de uso doméstico não atenderam aos padrões microbiológicos, enquanto seis (60%) não o foram para os padrões físico-químicos, para água de lavagem dos tetos evidenciaramse 13 (81,25%) e 10 (62,50%) amostras, respectivamente, fora dos padrões microbiológicos e físico-químicos vigentes. Não foi constatada contaminação microbiológica nem físico-química para água de uso em laticínio e em fábrica de polpa de frutas. Referente à água de uso em matadouro, uma (50%) amostra não atendeu aos padrões... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Water is a natural resource essential for life, it is essential to social promotion, food production and economic development. In order to evaluate the microbiological and physical chemistry quality of groundwater and surface water in the municipality of Itapecuru-Mirim-MA were collected 172 water samples, including 86 in the rainy season (March-May) and 86 samples in the dry weather period (August- October). From these total, 39 samples were water consumed in rural residences coming from shallow water wells, artesian water wells, natural sources and public water supply, 05 were domestic water, 08 from teat washings of cows; 02 for use in dairy products, 01 from the slaughterhouse, 01 from a factory fruit pulps, 18 from animal drinking fountains, 09 water samples used for pisciculture and 03 from vegetables irrigation. They were all analyzed for the microbiological and physical-chemical parameters. A close questionnaire with objective questions was also applied to evaluate the awareness level of people about the water quality used or consumed and the crops points were geographically mapped. The microbiological and physical-chemical results identified 52 (66,66%) water samples for human consumption in discordance with the microbiological standards and 23 (29,48%) in discord to the physical-chemical parameters, nine (90%) water samples for domestic use did not attend to the microbiological standards, while six (60%) were not for the physical-chemical parameters. The teat washing water results showed that 13 (81,25%) and 10 (62,50%) samples, respectively, were out of the microbiological and physical-chemical actual patterns. It was not detected microbiological contamination of water used in the dairy and in the fruit pulp factory. Referring to the water used in the slaughterhouse, one (50%) sample did not attend to the microbiological patterns, but all samples attended to the physical-chemical...(Complete abstract click electronic access below)
Doutor

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Kodavali, Swathi Sree. "Physico-chemical properties, and water and oil uptake characteristics of novel, soy-based snacks processed using extrusion." Thesis, Kansas State University, 2012. http://hdl.handle.net/2097/15055.

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Master of Science
Department of Grain Science and Industry
Sajid Alavi
Extrusion processing and frying are the two most commonly used methods to produce savory snacks. These snacks are mostly starch based and also contain high amounts of fat. Snacking percentage has increased drastically over the past few decades causing many health problems like obesity, hypertension and cardiovascular diseases. The overall objective of this study was to develop novel soy based savory snack that are high in protein and has less fat using both extrusion processing and frying. In the first part of this study both defatted soy (25-75%), wheat flour, monoglycerides (0.375 & 0.75%) and sodium bicarbonate (0 and 0.5%) were used to produce dense extrudates, which mimic the shape of lentils using pilot scale twin screw extruder. The extrudates were soaked in water and fried in corn oil to produced savory snacks. Soy influenced the water absorption during soaking and oil uptake during frying. The water uptake and % fat decreased with increase in soy and the amount of water uptake influenced the % fat absorption in the product. No significant differences were observed in overall acceptability and to summarize the increased protein and dense structure of the products challenge the texture of the products. In the second part of this research, dynamics of water and oil uptake were studied to see the role of texture modifiers like soy protein isolate (4, 8, & 12%), calcium bicarbonate (0.2, 0.4 & 0.6%) and pregelatinized wheat starch (4, 8, & 12%) on texture, water and oil uptake. Descriptive sensory analysis was conducted to study the sensory attributes of the products. Water holding capacity is influenced by the level of % starch addition and the degree of starch degradation during processing. Oil uptakes correlates to that of WHC and is also affected by the degree of gelatinization and crust formation. Degree of starch gelatinization, oil uptake and oil and starch matrix interactions had an impact on hardness. Among SPI, CaCO3 and PGWS, PGWS lowered the product hardness followed by SPI and CaCO3. Descriptive sensory results are similar to experimental results with PGWS samples having lower initial or substantial hardness and more oxidized or heated oil aroma and flavor.

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Birchill, Antony James. "The seasonal cycling and physico-chemical speciation of iron on the Celtic and Hebridean shelf seas." Thesis, University of Plymouth, 2017. http://hdl.handle.net/10026.1/10236.

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Shelf seas represent an important source of iron (Fe) to the open ocean. Additionally, shelf seas are highly productive environments which contribute to atmospheric carbon dioxide drawdown and support large fisheries. The work presented in this thesis describes the seasonal cycle of Fe in the Celtic and Hebridean Shelf Seas, and determines the physico-chemical speciation of Fe supplied from oxic margins. The results from repeated field surveys of the central Celtic Sea showed a nutrient type seasonal cycling of dissolved Fe (< 0.2 µm; dFe), which is surprising in a particle rich shelf system, suggesting a balance of scavenging and remineralisation processes. Coincident drawdown of dFe and nitrate (NO3-) was observed during the phytoplankton spring bloom. During the bloom, preferential drawdown of soluble Fe (< 0.02 µm; sFe) over colloidal Fe (0.02-0.2 µm; cFe) indicated greater bioavailability of the soluble fraction. Throughout summer stratification, it is known that NO3- is drawn down to < 0.02 µM in surface waters. This study revealed that both dFe and labile particulate Fe (LpFe) were also seasonally drawn down to < 0.2 nM. Consequently, it is hypothesised that the availability of Fe seasonally co-limits primary production in this region. At depth both dFe and NO3- concentrations increased from spring to autumn, indicating that remineralisation is an important process governing the seasonal cycling of dFe in the central Celtic Sea. In spring, summer and autumn, distinctive intermediate nepheloid layers (INL) were observed emanating from the Celtic Sea shelf slope. The INLs were associated with elevated concentrations of dFe (up to 3.25 ± 0.16 nM) and particulate Fe (up to 315 ± 1.8 nM) indicating that they are a persistent conduit for the supply of Fe to the open ocean. Typically > 15% of particulate Fe was labile and 60-90% of dFe was in the colloidal fraction. Despite being < 50 km from the 200 m isobath, the concentration of dFe was < 0.1 nM in surface waters at several stations. Broadly, the concentration of nutrients in surface waters described an oligotrophic environment where co-limitation between multiple nutrients, including Fe, appears likely. Over the Hebridean shelf break, residual surface NO3- concentrations (5.27 ± 0.79 µM) and very low concentrations of dFe (0.09 ± 0.04 nM) were observed during autumn, implying seasonal Fe limitation. The dFe:NO3- ratio observed is attributed to sub-optimal vertical supply of Fe relative to NO3- from sub-surface waters. In contrast to the shelf break, surface water in coastal regions contained elevated dFe concentrations (1.73 ± 1.16 nM) alongside low NO3-. Seasonal Fe limitation is known to occur in the Irminger and Iceland Basins; therefore, the Hebridean shelf break likely represents the eastern extent of sub-Arctic Atlantic seasonal Fe limitation, thus indicating that the associated weakening of the biological carbon pump exists over a wider region of the sub-Arctic Atlantic than previously recognised. These key findings demonstrate that the availability of Fe to phytoplankton may seasonally reach limiting levels in temperate shelf waters and that oxic margins persistently supply Fe dominated by colloidal and particulate fractions to the ocean.

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SANTOS, Romércia Batista dos. "Interface água e saúde: correlação com atividades agroindustriais desenvolvidas em um perímetro irrigado no Semiárido Paraibano." Universidade Federal de Campina Grande, 2013. http://dspace.sti.ufcg.edu.br:8080/jspui/handle/riufcg/707.

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Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-05-16T16:02:56Z No. of bitstreams: 1 ROMÉRCIA BATISTA DOS SANTOS - DISSERTAÇÃO PPGSA PROFISSIONAL 2013..pdf: 1113569 bytes, checksum: 29bd7b553a65415a734895bc13bc037a (MD5)
Made available in DSpace on 2018-05-16T16:02:56Z (GMT). No. of bitstreams: 1 ROMÉRCIA BATISTA DOS SANTOS - DISSERTAÇÃO PPGSA PROFISSIONAL 2013..pdf: 1113569 bytes, checksum: 29bd7b553a65415a734895bc13bc037a (MD5) Previous issue date: 2013-12-20
O presente trabalho propôs correlacionar atividades agroindustriais com a saúde humana e ambiental, tendo o Perímetro Irrigado de São Gonçalo-PB, como local de estudo. Para isto analisou-se a água bruta e tratada oriunda do referido perímetro, através de parâmetros físico-químicos e microbiológicos, como objeto maior de investigação. A pesquisa caracteriza-se de natureza quantitativa, qualitativa e descritiva. Foram georreferenciados oito pontos de amostragem, sendo que quatro pontos foram de água bruta e quatro de água tratada. As coletas foram realizadas em 2012, durante seis meses, considerando abril, maio e junho como período de inverno e, outubro, novembro e dezembro como época de seca. Fez-se também um levantamento dos indicadores básicos das condições sanitárias e socioambientais que refletem diretamente na saúde humana e no ecossistema. Os resultados físicoquímicos e microbiológicos foram avaliados com base nas legislações vigentes. Assim, foi possível constatar que tanto as amostras da água bruta e tratada, em relação aos atributos físico-químicos, estes se mantiveram dentro dos limites permitidos (Res. CONAMA 375/05 e Portaria MS nº2914/11, respectivamente). Os resultados microbiológicos constataram presença de coliformes, de presença total e termotolerantes para as amostras de água bruta, em ambos os períodos de inverno e verão. O critério de balneabilidade para estas mesmas águas apresentaram aspectos satisfatórios para o ponto A3 e A4 (ver pontos de análise) e impróprias para os pontos A6 e A8 (Res. CONAMA 274/2000). Assim, as águas tratadas revelaram focos de contaminação microbiológica em todos os pontos, observadas as delimitações da Portaria MS 2914/2011, pela presença de coliformes totais. As amostras de águas tratadas revelaram que nos núcleos habitacionais II e III (NHII-2 e NHIII-2) apontaram valores de Número Mais Provável (NMP) de coliformes totais e termotolerantes elevados, acreditando-se que tal contaminação esteja atribuída à má manutenção da rede hidráulica, e/ou higienização ineficiente. É importante informar que a média de chuvas no ano de 2012, período da pesquisa, foi abaixo do esperado, contribuindo para um decréscimo significativo em relação ao volume total em metros cúbicos (m³) do açude de São Gonçalo. Tal situação é preocupante, pois, a diminuição das águas é um indicador de eutrofização. Após análise, foi possível concluir que tais situações, como, por exemplo, o abastecimento e tratamento de água, destino dos dejetos e dos resíduos sólidos, refletem uma condição de prédisposição da população as doenças como também podem comprometer as atividades agroindustriais desenvolvidas no perímetro irrigado em estudo.
This paper proposed agribusiness activities correlate with human and environmental health, and the Irrigated Perimeter of São Gonçalo - PB, as a study. For this we analyzed the raw and treated water coming from said perimeter, through physical, chemical and microbiological parameters, such as increased under investigation. The research is characterized quantitative, qualitative and descriptive nature. Eight sampling were geocoded, and four points were raw water and treated water four. The collections were made in 2012, for six months, for April, May and June as period and reverse, October, November and December as the dry season. And he made a survey of the basic indicators of health and environmental conditions that directly influence human health and the ecosystem. The physico-chemical and microbiological outcomes were assessed based on the current legislation. Thus, it was found that both samples of raw water and treated in relation to physico-chemical properties, these remained within permitted limits (CONAMA Resolution 375/05 and MS Portaria No. 2914/11, respectively). The microbiological results found presence of coliforms, total and thermotolerant presence for raw water samples, in both winter and summer periods. The criteria for bathing waters showed satisfactory these same aspects for the A3 and A4 point (see point analysis) and unfit for A6 and A8 points (CONAMA Resolution 274/2000). Thus, the treated water showed foci of microbial contamination at all points, observing the boundaries of the MS 2914/2011, by the presence of total coliforms. Samples of treated water showed that the housing units II and III (and NHIII-2 NHII-2) showed values of more than Probable Number (MPN) of total coliforms and thermotolerant high, it is believed that such contamination is attributed to poor maintenance the hydraulic network, and / or inefficient cleaning. It is important to mention that the average rainfall in 2012, survey period, was lower than expected, contributing to a significant decrease in the total volume in cubic meters ( m³ ) Açude of São Gonçalo. This situation is worrying because, with the decrease of water promotes the process of eutrophication. After analysis of the indicators, it was concluded that such situations, for example, the supply and treatment of water, Sewage facilities and solid waste, reflect a pre-condition to the population as diseases can also compromise the agribusiness activities developed in the irrigated area under study.

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Vialle, Claire. "Etude du comportement hydraulique, physico-chimique et microbiologique d'un système de récupération d'eaux de toiture. Evaluation de l'empreinte environnementale." Thesis, Toulouse, INPT, 2011. http://www.theses.fr/2011INPT0060/document.

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L'objectif de ces travaux est de contribuer à augmenter la connaissance sur la réutilisation des eaux de ruissellement de toiture. Une maison individuelle située en zone rurale et équipée d'une toiture en tuiles, et un bâtiment collectif situé en zone périurbaine avec une toiture terrasse bitumée, ont été étudiés. Les eaux de pluie collectées sont réutilisées dans l'habitat pour l'alimentation des chasses d'eau. Un suivi analytique a permis l'étude de la qualité de l'eau en plusieurs points des systèmes. Les eaux stockées sont clairement non potables et révèlent une contamination microbiologique très variable. Des pathogènes ont été quantifiés à plusieurs reprises. La qualité de l'eau distribuée ne peut donc pas être garantie au cours de l'année, d'où la recommandation d'une désinfection de l'eau avant distribution. Un suivi hydraulique a permis de déterminer les volumes d'eau potable substitués et les taux de couverture de besoins en eau. Un modèle du comportement hydraulique a été développé puis utilisé pour discuter le dimensionnement des cuves. En présence d'une désinfection, les installations ne sont économiquement pas rentables. En l'absence de désinfection, le bilan économique est positif mais la période de retour sur investissement supérieure à la durée de vie de l'installation. Une première analyse de cycle de vie a été réalisée pour comparer les deux échelles étudiées. Dans les deux cas, les processus les plus impactants sont liés aux consommations électriques de l'éventuelle désinfection ultra-violet et des pompes. En présence d'une désinfection, l'échelle du bâtiment collectif présente des impacts plus faibles. Une deuxième analyse de cycle de vie a été réalisée pour étudier la pertinence de la substitution de l'eau du réseau d'eau public par de l'eau de pluie à l'échelle d'un particulier. Elle n'est pas probante d'un point de vue environnemental
The aim of this work is to contribute to knowledge on roof runoff reuse. A private house located in rural area with a tiled sloping roof and a research building located in suburban zone with a bituminous flat roof were studied. The collected rainwater is reused for toilet flushing. An analytical monitoring allowed the study of water quality in several points of the systems. Stored rainwater is clearly non drinkable and reveals a very variable microbiological contamination. Pathogenic agents were quantified on several occasions. Distributed water quality cannot thus be guaranteed over the year and a disinfection before distribution is recommended. A hydraulic follow-up made it possible to determine substituted volumes of drinking water by collected rainwater and water saving efficiencies. A model of the hydraulic behaviour of systems was developed then used to discuss dimensioning of the tanks. In the presence of disinfection, the installations are economically not profitable. In the absence of disinfection, the economic assessment is positive but the payback period is longer than the lifespan of the installation. A first life cycle assessment was carried out to compare the two studied scales. In both cases, the more impacting processes are related to electricity consumptions of possible ultra-violet disinfection and the pumps. In the presence of disinfection, the scale of the building presents weaker impacts. A second life cycle assessment was carried out to study the relevance of the substitution of drinking water by rainwater on a private individual scale. It is not convincing of an environmental point of view

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João, Jucimara Horstmann. "Caracterização da qualidade da água e do manejo de ordenha de propriedades do meio oeste catarinense e influência da qualidade da água na qualidade do leite cru resfriado." Universidade do Estado de Santa Catarina, 2009. http://tede.udesc.br/handle/handle/813.

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This present study evaluated the influence of water quality on the quality of cold raw milk on eight dairy farms in the Midwest Catarinense Region, considering the current legal standards of drinking water (MS Decree 518/2004 and MAPA IN 62/2003 ) and milk quality (MAP Normative Instruction 51/2002 ). Samples of water used to sanitize eighty dairy farms located in the Midwest Catarinense region were collected for chemical and microbiological analysis, and the data from the samples of cold raw Milk were provided by the dairy industry, having been carried by the Milk quality laboratory - CIDASC / UNC, Concordia / SC. Among the analysis of water, the following were carried out: hardness, pH, coliforms at 35 º C, 45 C and standard plate count (PPC). The analysis of cold raw milk were percentage content of fat, protein, total dry extract (EST), defatted dry extract (ESD), countings of aerobic microorganisms - total bacterial counting (CBT) and counting of somatic cells (CCS). Accordingly, the degree of information and consciousness of producers were studied, regarding the quality of water used and / or consumed on the property. From the data collected, the effects of variables on water quality, and influence of water quality on the quality of milk in these properties were analyzed. This study found that the chemical parameters of water did not affect the quality of milk. But the standard plate count (PPC) of the water used for sanitizing the equipment affected the linear CBT milk, However, it did not influence the SCC. Although 23.68% of samples were contaminated with coliform to 45oC, these were not correlated with the milk quality in CBT and SCC
O presente trabalho avaliou a influência da qualidade da água na qualidade do leite cru resfriado de 80 propriedades leiteiras na Região do meio Oeste Catarinense, considerando os atuais padrões legais de potabilidade da água (Portaria 518/2004 do MS e IN 62/2003 do MAPA) e de qualidade do leite (Instrução Normativa 51/2002 do MAPA). Foram coletadas amostras da água utilizada para higienização de 80 propriedades leiteiras localizadas na região do meio Oeste Catarinense para a realização de análises químicas e microbiológicas, e os dados das amostras de leite cru resfriado foram fornecidos pela indústria de laticínios, tendo sido realizadas pelo laboratório de qualidade do leite - CIDASC/UnC, Concórdia/SC. Dentre as análises de água, foram realizadas: dureza, pH, coliformes a 35ºC, 45ºC e contagem padrão em placas (CPP). Dentre as análises de leite cru resfriado, foi realizado: teor percentual de gordura, proteína, extrato seco total (EST) e extrato seco desengordurado (ESD), além da contagem de microrganismos aeróbioscontagem bacteriana total (CBT) e contagem de células somáticas (CCS). Concomitantemente, foi estudado o grau de informação e consciência dos produtores com relação à qualidade da água utilizada e/ou consumida na propriedade. A partir dos dados levantados foram analisados os efeitos das variáveis estudadas sobre a qualidade da água e a influência da qualidade da água sobre a qualidade do leite nestas propriedades. O presente estudo verificou que os parâmetros químicos da água não influenciaram na qualidade do leite. Mas a contagem padrão em placas (CPP) da água utilizada para a higienização dos equipamentos afetou linearmente a CBT do leite, porém, não influenciou a CCS. Apesar de 23,68% das amostras estarem contaminadas com coliformes a 45oC estas não tiveram correlação com a qualidade microbiológica- CBT e CCS do leite

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Serhan, Mireille. "Valorisation durable des laits de chèvre de la région du Nord Liban. Transformation en fromage "Darfiyeh" et établissement de caractéristiques physico-chimiques et microbiologiques en vue de la création d'une appellation d'origine." Thesis, Vandoeuvre-les-Nancy, INPL, 2008. http://www.theses.fr/2008INPL073N/document.

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Afin de contribuer à la préservation du patrimoine laitier libanais, l'objectif principal de cette étude a été de caractériser le fromage Darfiyeh, une variété traditionnelle fabriquée à partir de lait de chèvre cru et affinée dans une outre en peau de chèvre. Parallèlement à cet objectif, et pour mieux comprendre l'affinage du Darfiyeh, le transfert de composés d’arôme à travers la peau de chèvre a été étudié au moyen d’un dispositif expérimental original. Trois lots indépendants de production de Darfiyeh ont été analysés après 20, 40 et 60 jours d'affinage. Les résultats des analyses physico-chimiques ont montré que le Darfiyeh est un fromage à pâte mi-dure, caractérisé par une protéolyse et une lipolyse modérées. Le 3-méthyl butanal, le 1-phényl éthanol et le 1-octanol contribuent à la fraction aromatique particulière du Darfiyeh. Les analyses microbiologiques ont mis en évidence (Log cfu.g-1 fromage) des lactobacilles mésophiles (7,1-10,4), des bactéries lactiques (BL) thermophiles cocciformes (6,6-8,4) et des lactobacilles thermophiles (5,5-7,2). Afin d'explorer l'écosystème naturel du Darfiyeh, une combinaison d'approches classiques et moléculaires a été appliquée. L'identification classique a révélé des espèces appartenant aux genres Streptococcus, Enterococcus, Lactococcus et Lactobacillus. Les profils de Temporal Temperature Gel Electrophoresis (TTGE) ont révélé des bandes communes avec l'identification classique. Des analyses menées par PCR spécifiques de l'espèce bactérienne ont confirmé la présence of S. thermophilus, E. faecium, E. durans, Lc. lactis subsp. lactis et Lc. lactis subsp. cremoris. La PCR en temps réel a permis la quantification de S. thermophilus et d' E. faecium, avec un seuil de détection respectif de 104 ufc.g-1 de Darfiyeh et une gamme de 107-109 ufc.g-1 de Darfiyeh, respectivement. Pour le transfert d'arômes à travers la peau de chèvre, l'absorption et la perméabilité de trois molécules aromatiques modèles (2-butanone, 2,3-butanedione, 2-butanol) dans un système solution aqueuse/peau de chèvre a été suivi, après 20, 40 et 60 jours d'exposition. Jusqu'à 40 j d'exposition, le transfert des molécules aromatiques était régi par leurs propriétés physico-chimiques et par le temps d'exposition. Après 60 j, le système solution aqueuse/peau s’est traduit par une tendance à la migration des molécules modèles depuis la peau vers la solution simulée de Darfiyeh. Autrement dit, le transfert de ces molécules modèles dans le système simulé paraît s’établir de façon cyclique. Ce travail est une première contribution scientifique et technique au secteur de la valorisation durable de la tradition fromagère libanaise
In order to contribute for the preservation of the Lebanese dairy heritage, the aim of this study was to characterize Darfiyeh cheese, a traditional variety made from raw goats' milk and ripened in goat's skin. Parallel to this objective, and for a better understanding of Darfiyeh ripening, aroma transfer towards goat skin was conducted through an experimental device. Three independent batches of Darfiyeh production were analyzed after 20, 40 and 60 days of ripening. Physico-chemical results showed that Darfiyeh is a semi-hard goat's milk cheese which undergoes a moderate proteolysis and lipolysis. 3-methyl butanal, 1-phenyl ethanol and 1-octanol contribute to the distinctive aromatic fraction of Darfiyeh. As for microbiological results, bacterial counts (Log cfu.g-1 cheese) for mesophilic lactobacilli (7.1-10.4), thermophilic coccal-shaped lactic acid bacteria (LAB) (6.6-8.4) and thermophilic lactobacilli (5.5-7.2) were found. In order to explore Darfiyeh natural ecosystem, a combination of classical and molecular approaches was applied. Classical identification revealed members of the genera Streptococcus, Enterococcus, Lactococcus and Lactobacillus. Temporal Temperature Gel Electrophoresis (TTGE) profiles revealed common bands between the classical identification. Species-specific polymerase chain reactions (PCR) confirmed the presence of S. thermophilus, E. faecium, E. durans, Lc. lactis subsp. lactis and Lc. lactis subsp. cremoris. Real time PCR enabled quantification of S. thermophilus and E. faecium, with a detection threshold of 104 ufc.g-1 of Darfiyeh and a range of 107-109 ufc.g-1 of Darfiyeh, respectively. As for aroma transfer towards goat skin, absorption and permeability of three model aroma molecules (2-butanone, 2,3-butanedione, 2-butanol) in aqueous solution/goat skin system were followed, after 20, 40 and 60 days of exposure. Until 40 days, the transfer of aroma molecules was dependent on their physico-chemical properties and exposure time. After 60 days, the molecules migrate from the skin to the aqueous solution. Therefore, in such a simulated system, aromatic molecules seem to move under a cyclic way. This work is a first scientific and technical contribution to the preservation of traditional Lebanese cheesemaking

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Holderer, Olaf-Notker Esnouf Claude. "Nano-structural and physico-chemical analysis of Pd-Sn colloidal solutions applied to the metallisation of polymers alyse nano-structurale et physico-chimique de solutions colloïdales Pd-Sn appliquée à la métallisation des polymères /." [S.l.] : [s.n.], 2002. http://csidoc.insa-lyon.fr/these/2002/holderer/index.html.

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Nyembwe, Patricia. "Sensory and physico-chemical analysis of roasted marama beans [Tylosema esculentum (Burchell) A. Schreiber] with specific focus on compounds that may contribute to bitterness." Diss., University of Pretoria, 2013. http://hdl.handle.net/2263/79294.

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Marama bean [Tylosema esculentum (Burchell) A. Schreiber] is an underutilized legume which grows wild in selected part of southern Africa and forms part of the diet for the indigenous population in this area. Marama bean seeds are not eaten raw but after roasting they have a delicious nutty flavour. A bitter taste develops depending on the extent of heating. Heat treatment by roasting marama beans at 150 °C for 20 min inactivates anti-nutritional factors particularly trypsin inhibitor. The bitter taste can limit the utilisation and consumption of this pulse. Research is lacking on the compounds that could be responsible for the bitter taste in marama beans. Different chemicals including phenolic compounds and saponins contribute to bitterness in many edible legumes. An increase in the quantity of the bitter substances in roasted marama bean might contribute to more bitter taste. In this study sensory profiles and potential bitter substances of marama bean cotyledons were investigated as a function of roasting time. Marama beans were roasted at 150 °C for different time periods 20, 25 or 30 min. Three pastes were prepared from the roasted cotyledons; paste20, paste25 and paste 30. Eight samples of water extracts were prepared from full fat and defatted flours from roasted and unroasted marama cotyledons. Descriptive sensory evaluation was conducted with a trained panel to rate the intensity of aroma and flavour attributes of marama pastes and bitterness of water extracts. Marama pastes were subjected to colour measurement, lightness (L*), red/green characteristics (a*) and blue/yellow characteristics (b*). The total phenolic and saponin contents of marama water extracts were determined. The phenolic profile were analysed by reverse phase-high performance liquid chromatography (RP-HPLC). The paste20 was lighter and the least bitter while paste30 was dark-coloured and the most bitter. The water extracts prepared from unroasted flours were rated the least bitter while the water extract prepared from defatted flour made from marama bean roasted for 30 min was the most bitter. Roasting of marama seeds resulted in significant increases in its water soluble phenolic content. The concentration of total phenolics in the seeds roasted for longer time periods was higher. The major extractable phenolic acids present in marama water extracts were found to be gallic and protocatechuic acids, the concentrations of which increased as a function of roasting time and may be the cause of more intense bitterness. Marama beans have saponins content varying from 84.4 mg/100 g in raw flour to 94.9 mg/100 g in roasted flour. The different concentrations of saponins in water extracts prepared from roasted and unroasted marama flour (55-62 mg/L) were higher than the reported bitter threshold value for saponins in water (2-12 mg/L). Thus, saponins in marama beans possibly also contributed to more bitterness. Roasting time and temperature combinations shoud be considered when processing marama beans for food products. At 150 ˚C roasting temperature, marama beans should not be roasted for more than 20 min to avoid bitterness, colour darkening as well as development of a burnt flavour.
Dissertation (MSc)--University of Pretoria, 2014.
Food Science
MSc
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47

Loodts, Vanessa. "Influence of chemical reactions on convective dissolution: a theoretical study." Doctoral thesis, Universite Libre de Bruxelles, 2016. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/242093.

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Studying the coupling between buoyancy-driven instabilities and chemical reactions is not only relevant to fundamental research, but has also recently gained increased interest because of its relevance to CO$_2$ sequestration in subsurface geological zones. This technique aims to limit the emissions of CO$_2$ to the atmosphere, with a view to mitigating climate change. When injected in e.g. a saline aquifer, CO$_2$ dissolves into the brine occupying the geological formation, thereby increasing the density of the aqueous phase. This increase of density upon dissolution leads to a denser fluid boundary layer rich in CO$_2$ on top of less dense fluid in the gravity field, which drives dissolution-driven convection. This process, also called convective dissolution, accelerates the transport of dissolved CO$_2$ to the host phase and thus improves the safety of CO$_2$ sequestration. The same kind of instability can develop in other contexts involving the dissolution of a phase A into a host phase, such as solid dissolution or transfer between partially miscible liquids. In this context, the goal of our thesis is to understand how chemical reactions coupled to dissolution-driven convection affect the dynamics of the dissolving species A in the host solution. To do so, we introduce a general reaction of the type A + B $rightarrow$ C where A, B and C affect the density of the aqueous solution. We theoretically analyze the influence of the relative physical properties of A, B and C on the convective dynamics. Our theoretical analysis uses a reaction-diffusion-convection model for the evolution of solute concentration in a host fluid solvent occupying a porous medium. First, we quantify the characteristic growth rate of the perturbations by using a linear stability analysis. Thereby we show that a chemical reaction can either accelerate or slow down the development of convection, depending on how it modifies the density profile that develops in the reactive solution. In addition, new dynamics are made possible by differential diffusion effects. Then, by analyzing the full nonlinear dynamics with the help of direct numerical simulations, we calculate the dissolution flux into the host phase. In particular, the dissolution flux can be amplified when convection develops earlier, as CO$_2$ is then transported faster away from the interface. Finally, we compare these theoretical and numerical predictions with results of laboratory experiments and discuss the possible implications of this study for CO$_2$ sequestration.
Doctorat en Sciences
info:eu-repo/semantics/nonPublished

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48

Kizzie-Hayford, Nazir. "Development of strategies for the successful production of yogurt-like products from Tiger nut (Cyperus esculentus L) milk." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-221091.

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Tiger nuts (Cyperus esculentus L) are recognized as a high potential, alternative source of food nutrients. However, there is limited scientific literature on the technological possibilities for developing value-added foods, such as fermented products from tiger nut milk. Therefore, strategies for producing and improving the properties of fermented tiger nut milk were investigated for generating lactose-free, nutritious yogurt-like products with acceptable sensory properties and a prolonged shelf life quality. A wet-milling procedure was standardized for extracting tiger nut milk from tiger nuts, and the effects of the extraction process on nutrient distribution, colour properties and colloidal stability of the milk were analyzed. Next, tiger nut milk was enriched with proteins and/or hydrocolloids and the impact of the additives on the physical properties of the milk were determined. Enriched tiger nut milk was fermented by using classical yogurt cultures and the obtained products were analyzed for the microbiological, physico-chemical and sensory characteristics. Additionally, effects of enriching tiger nut milk with microbial transglutaminase cross-linked proteins on the microbiological and physico-chemical properties were evaluated. Higher wet-milling intensity improved the nutrient composition, colloidal stability and colour of the milk. Enrichment of tiger nut milk with milk proteins and xanthan gum enhanced the viscosity and stability, and after fermentation, led to homogenous gel-like products with superior microbiological, physico-chemical and different sensory properties compared to the fermented plain tiger nut milk. Microbial transglutaminase cross-linked proteins improved the physical characteristics of the fermented product, especially during storage. This product would be relevant in many developing countries with high prevalence of lactose intolerance, limited access to nutritious food but show a high distribution of tiger nut vegetation
Erdmandeln (Cyperus esculentus L) haben ein hohes Potential als alternative Quelle Lebensmittelinhaltsstoffen. Allerdings gibt es nur in begrenztem Ausmaß Literatur über technologische Möglichkeiten zur Entwicklung von Mehrwert-Lebensmitteln wie fermentierter Erdmandelmilch. Daher wurden Strategien zur Herstellung und Verbesserung der Eigenschaften von fermentierter Erdmandelmilch zur Erzeugung laktosefreier joghurtähnlicher Produkte mit akzeptablen sensorischen Eigenschaften untersucht. Für die Extraktion der Erdmandelmilch wurde ein Nassmahlverfahren standardisiert und der Einfluss des Verfahrens auf die Nährstoffverteilung, die Farbeigenschaften und die kolloidale Stabilität der Milch analysiert. Als nächstes wurde Erdmandelmilch mit Proteinen und/oder Hydrokolloiden angereichert, und der Einfluss der Additive auf die physikalischen Eigenschaften des Extrakts bestimmt. Angereicherte Erdmandelmilch wurde mit klassischen Joghurtkulturen fermentiert, und die mikrobiologischen, physikalisch-chemischen und sensorischen Eigenschaften der Produkte wurden untersucht. Zusätzlich wurden Effekte der Anreicherung von Erdmandelmilch mit enzymatisch vernetzten Proteinen auf die mikrobiologischen und physikalisch-chemischen Eigenschaften bewertet. Eine höhere Nassmahlintensität verbesserte die Nährstoffzusammensetzung, die kolloidale Stabilität und die Farbe der Milch. Die Anreicherung erhöhte die Viskosität und Stabilität und führte nach der Fermentation zu homogenen gelartigen Produkten mit verbesserten mikrobiologischen, physikalisch-chemischen und sensorischen Eigenschaften im Vergleich zur fermentierten Erdmandelmilch. Mikrobielle Transglutaminase-vernetzte Proteine verbesserten die physikalischen Eigenschaften des fermentierten Produkts, insbesondere während der Lagerung. Dieses Produkt wäre in vielen Entwicklungsländern mit hoher Prävalenz von Laktoseintoleranz und begrenztem Zugang zu nahrhaften Lebensmitteln als Alternative von Interesse

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Eberle, Alexander Richard [Verfasser], and Wolfgang [Akademischer Betreuer] Schmahl. "Growing low-dimensional supramolecular crystals via Organic Solid-Solid Wetting Deposition : physico-chemical basis, structure analysis, and doping of graphene / Alexander Richard Eberle ; Betreuer: Wolfgang Schmahl." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2019. http://d-nb.info/119342321X/34.

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50

Essandoh, Ernest. "Structural studies of organic crystals of pharmaceutical relevance : correlation of crystal structure analysis with recognised non-bonded structural motifs in the organic solid state." Thesis, University of Bradford, 2009. http://hdl.handle.net/10454/4444.

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Pharmaceutical solids tend to exist in different physical forms termed as polymorphs. Issues about pharmaceutical systems are mainly concerned with the active ingredient's physico-chemical stability and bioavailability. The main aim of this study is to investigate the non-bonded interactions in pharmaceutical solids that govern the physical pharmaceutics performance of such materials and through the use of structural techniques and correlation of these results with crystal structural database to establish the presence of physical motifs in selected systems. Structural motifs were identified by the use of single crystal and crystal packing analysis on diverse range of pharma-relevant materials including chalcones, cryptolepines, biguanides and xanthines. These selected systems were validated using functional group and molecular analysis and correlating them to the Cambridge Structural Database. Crystallization studies are done on these selected systems as well as exploiting those using synthetic analogues. A total of 51 crystal structures were investigated including 16 new structure determinations. Addition synthesis of new xanthines to investigate novel intermolecular patterns was also undertaken. The understanding and exploitation of intermolecular interactions involving hydrogen bonds and coordination complexation during packing can be used in the design and synthesis of solid state molecular structures with desired physical and chemical properties.

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Dissertations / Theses on the topic 'Physico- chemical and microbiological analysis'

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