Dissertations / Theses on the topic 'Physicochemical process'

Thesis (M.S.)--University of Missouri-Columbia, 2007.
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on January 16, 2008) Includes bibliographical references.

Le but de ce travail était d'essayer de comprendre dans quelles mesures les non-sucres présents dans les sirops de sucre ont un effet néfaste sur la cristallisation du saccharose et sur la qualité du sucre obtenu. Pour réaliser cette étude nous avons étudié comparativement différents échantillons industriels de différents origines. Cette étude a nécessité la mise en œuvre d'un certain nombre de techniques de séparation et de fractionnement (ultrafiltration, dialyse, chromatographie d'échange d'ions et d'exclusion stérique. . . ). La combinaison de ces méthodes nous a permis de montrer que l'EP2 danois contient davantage de polyosides de poids moléculaire supérieur à 10000 daltons à caractère non chargés que l'EP2 d'Eppeville. En revanche les fractions moléculaires comprises entre 2000 et 10000 daltons ne semblent pas montrer de différences significatives. On notera que les produits traités industriellement par des résines reminéralisantes et décolorantes ne comportent pratiquement plus de macromolécules. Le relargage à l'alcool des substances colloïdales est un test classique de contrôle, nous avons tenté de l'appliquer aux différents produits sucrés industriels. Nous avons ainsi pu montrer que les non-sucres des EP2 danois sont globalement moins hydrophile que ceux de la sucrerie française qui nous a servi de référence, ce résultat est intéressant car le sucre roux danois obtenu à partir de cet EP2 est de bien meilleure qualité que le sucre roux d'Eppeville. Les macromolécules présentes dans les sirops proviennent en partie de la dégradation des polysaccharides de la betterave qui ont échappé à l'épuration calco-carbonique industrielle, pour comprendre ce phénomène, nous avons montré que la dégradation alcaline des pulpes touche essentiellement les pectines, en revanche hémicelluloses et cellulose résistent bien aux pH basiques. Ce résultat est intéressant pour un approfondissement ultérieur de la connaissance de ces macromolécules. Enfin, dans un but d'application industrielle, nous nous sommes intéressés à l'étude de la valorisation des pulpes de betteraves (décoloration et prévention de l'oxydation des lipides présents) ainsi qu'à l'étude de différentes propriétés fonctionnelles du produit obtenu

A obtenção da sílica vítrea pelo processo de sinterização por plasma pulsado (SPS), a partir de matérias-primas de diferentes estruturas (cristalina e amorfa) e diferentes granulometrias, foi investigada. Análises de difração de raios X, transmitância óptica, microscopia óptica e eletrônica de varredura, e medições de densidade foram realizadas nas amostras sinterizadas. Sílicas vítreas transparentes foram fabricadas a partir de pós de quartzo atingindo-se temperaturas finais entre 1450 e 1600°C, enquanto que nanopó e pó amorfo de sílica formaram consolidados transparentes com temperaturas máximas próximas de 1200° C. Taxas de aquecimento entre 40 e 150°C/min. foram utilizadas nas sinterizações, com tempos de processo menores que 40 minutos. As maiores taxas de aquecimento exigiram uma maior temperatura final para a fusão completa do material cristalino e causaram, de forma indireta, a presença de aglomerações de micro-bolhas nas amostras obtidas com o nanopó. Um gradiente radial de temperatura (decrescente do centro para as bordas) foi observado nos consolidados fabricados com os pós cristalinos, facilitando o processo de fechamento da porosidade aberta. A presença ou ausência de material não fundido e de bolhas nas amostras foram analisadas por difratogramas de raios X, microscopia óptica e medidas de densidade. A análise da transmitância indicou uma quantidade praticamente nula de grupos OH nos compactos sinterizados com os pós cristalinos e em torno de 20 ppm no caso dos sólidos fabricados com matéria-prima sol-gel. Amostras de nanopós de sílica dopada com titânia (~6% em massa) foram processadas com temperaturas finais de 1200 e 1400°C apresentando coloração azulada e negra, respectivamente, e aumento dos clusters de titânia para a temperatura mais elevada. A sinterização a uma temperatura em torno 1200°C mantida por apenas 4 minutos resultou na conversão completa da fase anatase para a fase rutilo da titânia.
The production of vitreous silica by the spark plasma sintering (SPS) process, starting from raw materials of different structures (crystalline and amorphous) and granulometry were investigated. Analysis of X-ray diffraction, optical transmittance, optical and scanning electron microscopy, and density measurements were performed on the sintered compacts. Transparent vitreous silica was fabricated from quartz powder at final temperatures ranging from 1450 and 1600°C while silica nanopowder and silica powder formed transparent compacts at temperatures around 1200°C. Heating rates between 40 and 150° C/min. were used in processes with durations smaller than 40 minutes. Higher heating rates demanded higher final temperatures to complete the fusion process and caused, indirectly, the formation of micro-bubbles agglomerations in the samples produced from the nanopowder. A radial gradient of temperature (decreasing from the center to the border) was observed at the compacts fabricated with the crystalline powders favoring the closure of the open porosity. The presence or the absence of non-fused material and bubbles in the samples was analyzed by X-ray diffraction, optical microscopy and density measurements. The transmittance analysis indicated an almost zero quantity of OH groups in the compacts sintered from crystalline powders and about 20 ppm in the solids fabricated from the sol-gel raw material. Nanopowder samples of silica titania (~6 wt % of titania) were processed with final temperatures of 1200°C and 1400°C presenting blue and black coloration, respectively, and an increase of the titania clusters for the highest temperature. The sintering at temperatures near 1200°C with a holding time of just 4 minutes caused the complete anatase-rutile conversion in titania.

La problématique de l'élimination de l'excès d'ions fluorure présents dans les eaux de forage destinées à la consommation humaine peut être résolue en utilisant plusieurs méthodes. Dans cette thèse, les procédés testés sont : l'adsorption sur des particules d'os de seiche, l'adsorption sur des particules de calcite en présence d'acide acétique, la nanofiltration et l'échange d'ions. L'objectif est d'optimiser les différents procédés pour des solutions modèles en ions fluorure, puis de réaliser pour ces conditions optimales le traitement d'une eau de forage tunisienne. La concentration limite en ions fluorure imposée par la WHO est de 1.5 mg.L-1. Les essais d'adsorption en utilisant l'os de seiche, disponible en Tunisie, sont simples à mettre en œuvre et permettent des traitements à petite échelle avec des coûts très compétitifs en utilisant un matériau non toxique. La défluoration de l'eau souterraine avec l'os de seiche présente une concentration résiduaire en fluorure de 1,3 mg.L-1 (TR = 61,5%). Dans le cas de la précipitation des ions fluorures sous forme de fluorite suivi de microfiltration, l'addition d'acide acétique aux particules de calcite (CaCO3) favorise l'élimination des ions fluorure. La défluoration de l'eau souterraine montre que l'eau traitée présente une concentration résiduaire en fluorure de 1,24 mg.L-1 (TR = 53,7%). En utilisant une résine échangeuse d'ions Purolite A520E, la défluoration de l'eau souterraine montre que l'eau traitée présente une concentration résiduaire en fluorure de 1,2 mg.L-1 (TR = 54%). La nanofiltration permet de traiter des volumes importants d'eau et les taux de rétention des ions fluorure sont satisfaisants (88% et 57%)

Orientadores: Florencia Cecilia Menegalli, Miriam Dupas Hubinger
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: Este trabalho teve como objetivo a obtenção de tomate em pó através do processo de secagem por atomização da polpa de tomate. Os experimentos foram conduzidos utilizando um atomizador de bancada e maltodextrina 10DE foi empregada como agente carreador. Foi utilizado um delineamento central composto rotacional (DCCR) para estudar a influência das seguintes variáveis independentes: temperatura do ar de secagem (153 a 187 °C), vazão de alimentação (0,57 a 0,83 l/h) e concentração de maltodextrina (3,3 a 11,7%). As variáveis de resposta foram o rendimento de produto e as seguintes características do tomate em pó: diâmetro médio de partícula, conteúdo de umidade, atividade de água, densidade do leito, higroscopicidade, solubilidade, tempo de instantaneização, retenção de carotenóides e retenção de ácido ascórbico. Os pós de tomate também foram caracterizados quanto à distribuição de tamanho de partículas e cor. Todas as variáveis mostraram influência significativa sobre as características do produto em pó, sendo que a concentração de maltodextrina foi a variável com efeito significativo sobre a maioria das respostas (rendimento, diâmetro médio de partícula, umidade, densidade do leito, higroscopicidade, tempo de instantaneização, retenção de carotenóides e retenção de ácido ascórbico), além de sua interação com a temperatura do ar de secagem. A análise das superfícies de resposta indicou que a produção de um pó com menor conteúdo de umidade, higroscopicidade, tempo de instantaneização e maior retenção de carotenóides pode ser conseguida utilizando-se temperatura do ar de secagem de 160 °C, vazão de alimentação de 0,62 l/h e concentração de maltodextrina de 10%, considerando a polpa de tomate com 5% de sólidos totais. Para as demais respostas (rendimento, diâmetro médio de partícula, atividade de água, densidade aparente, solubilidade e retenção de ácido ascórbico), os modelos obtidos não foram estatisticamente significativos, dentro da faixa de valores utilizada para cada variável independente do planejamento experimental. O tomate em pó obtido por atomização apresentou grande potencial de utilização, devido às suas propriedades como solubilidade e alta retenção de ácido ascórbico, além do baixo conteúdo de umidade e atividade de água, que facilitam seu armazenamento e transporte
Abstract: The objective of this work was to obtain tomato powder by spray drying of tomato pulp. The process was carried out using a laboratory spray dryer and maltodextrin 10DE was used as carrier agent. A central composite rotatable design (CCRD) was used to estimate the influence of the following independent variables: inlet air temperature (153 to 187 °C), feed flow rate (0.57 to 0.83 l/h) and maltodextrin concentration (3.3 to 11.7%) on the product yield and on the powder properties of the powder. The evaluated characteristics in tomato powder were: mean diameter, moisture content, water activity, bulk density, hygroscopicity, solubility, wetting time, carotenoids retention and ascorbic acid retention. Tomato powder was also characterized for particle size distribution and color. All variables had significant influence on the characteristics of the tomato powder and the maltodextrin concentration was the variable with significant effect on most of the responses (product yield, mean diameter, moisture content, bulk density, hygroscopicity, wetting time, carotenoids retention and ascorbic acid retention), besides its interaction with the inlet air temperature, at a 90% confidence interval. The response surface analysis indicated that obtaining a product with lower moisture content, lower hygroscopicity, lower wetting time and higher carotenoids retention can be achieved by using the inlet air temperature of 160 °C, feed flow rate of 0.62 l/h and maltodextrin concentration of 10%, considering the tomato pulp with 5% total solids. For the responses: process yield, mean diameter, water activity, bulk density, solubility and ascorbic acid retention, the models obtained were not statistically significant, within the levels used for each independent variable in experimental design. Tomato powder, obtained by spray drying, showed a great potential to several applications, due to its properties such as solubility and high ascorbic acid retention, besides the low moisture content and water activity that facilitate its storage and transport
Mestrado
Mestre em Engenharia de Alimentos

Orientadores: Miriam Dupas Hubinger, Catherine Brabet
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: O presente trabalho teve como objetivo a obtenção do suco de açaí em pó pelo processo de spray drying. Inicialmente, avaliou-se a influência das condições de processo sobre a umidade, higroscopicidade, a retenção de antocianinas e o rendimento do processo, através de um delineamento composto central rotacional 23 completo. A partir das condições selecionadas nessa primeira etapa (temperatura de secagem de 140ºC, vazão mássica de 15g/min e 6% de agente carreador), foram produzidas partículas utilizando quatro diferentes tipos de agentes carreadores: maltodextrina 10DE, maltodextrina 20DE, goma arábica e fécula de mandioca. Essas partículas foram então submetidas a uma caracterização físico-química, sendo analisadas em relação às seguintes propriedades: umidade, atividade de água, densidade, porosidade, solubilidade, molhabilidade, distribuição do tamanho de partículas, morfologia, cor, polifenóis totais, antocianinas e atividade antioxidante. As amostras produzidas com maltodextrina 20DE e com goma arábica apresentaram maiores valores de umidade e atividade de água, e menor tamanho de partículas., enquanto as produzidas com fécula de mandioca apresentaram menor solubilidade e porosidade e maior densidade aparente e molhabilidade, maior diâmetro médio e maior perda de polifenóis e antocianinas durante o processo de secagem. Em seguida, avaliou-se a estabilidade destas partículas, quando expostas a diferentes umidades relativas, através da construção de isotermas de sorção e da determinação da temperatura de transição vítrea. As amostras produzidas com fécula de mandioca foram apresentaram menor higroscopicidade, seguidas pelas produzidas com maltodextrina 10DE. A temperatura de transição vítrea diminuiu com o aumento do teor de umidade das amostras, confirmando o efeito plasticizante da água sobre esta propriedade. Por fim, realizou-se um estudo da estabilidade das antocianinas e da atividade antioxidante nos pós estocados em diferentes condições de temperatura e umidade relativa. O aumento nessas duas condições resultou em uma maior degradação das antocianinas. A atividade antioxidante das amostras também diminuiu com o aumento da umidade relativa, mas aumentou com o aumento da temperatura de estocagem. As partículas produzidas com maltodextrina 10DE foram as que apresentaram maiores tempos de meia-vida, seguidas pelas produzidas com goma arábica
Abstract: The objective of this work was to obtain a powdered açaí juice by spray drying. The influence of process conditions on the moisture content, hygroscopicity, anthocyanin retention and process yield was evaluated using a 23 experimental design. From the conditions selected in this first section, (inlet air temperature of 140ºC, feed flow rate of 15 g/min and 6% of carrier agent), particles were produced with four types of carrier agents: maltodextrin 10DE, maltodextrin 20DE, gum Arabic and tapioca starch. These particles were then characterized with respect to moisture content, water activity, density, porosity, solubility, wettability, particles size distribution, morphology, color, total polyphenolics, anthocyanin content and antioxidant activity. The samples produced with maltodextrin 20DE and with gum Arabic exhibited the highest moisture content and water activity, and the lowest particles size. The particles produced with tapioca starch were the less soluble, less porous and with the lowest bulk density and wettability, highest mean diameter and highest poliphenolic and anthocyanin loss, during the spray drying process. Particles stability, when exposed to different relative humidities, was evaluated through the construction of sorption isotherms and determination of the glass transition temperature. The samples produced with tapioca starch were the less hygroscopic, followed by those produced with maltodextrin 10DE. Glass transition temperature decreased with increasing moisture content, confirming the plasticizant effect of water on this property. Finally, a study about anthocyanin stability and antioxidant activity of powders stored at different temperatures and relative humidities was carried out. The increase of both these conditions resulted in higher anthocyanin degradation. The antioxidant activity also decreased with increasing relative humidity, but increased with increasing temperature. The particles produced with maltodextrina 10DE showed the highest half-life followed by those produced with gum Arabic
Doutorado
Doutor em Engenharia de Alimentos

Orientador: Míriam Dupas Hubinger
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: O presente trabalho teve como objetivo a obtenção de hidrolisado protéico de pele de cação em pó pelos processos de hidrólise enzimática e secagem por atomização. Na primeira etapa, foi estudado o processo de hidrólise utilizando a enzima comercial ProtamexTM, visando a otimização do processo para a recuperação de peptídeos de baixo peso molecular. A influência da temperatura, do pH e da relação Enzima/Substrato sobre o grau de hidrólise, recuperação de proteína e cinética enzimática foram avaliadas. As condições ótimas de processo foram fixadas em: 51 °C, 4,0% p/p de enzima e pH 7,1. Nessas condições, o hidrolisado obtido foi caracterizado em termos de composição química, composição de aminoácidos e distribuição de tamanho de peptídeo. O grau de hidrólise atingiu 19,3%, recuperou-se 90,3% do total da proteína presente na matéria-prima e o peso molecular foi inferior a 6,5 kDa. Na segunda etapa do projeto, foi avaliada a influência das variáveis do processo de secagem por atomização sobre as propriedades físico-químicas e antioxidantes do hidrolisado protéico de pele de cação em pó, usando maltodextrina (DE=10) como agente carreador. A temperatura do ar e a concentração de agente carreador foram variadas. As respostas analisadas foram a umidade final, a atividade de água, a densidade aparente, a higroscopicidade, o tamanho de partícula e a capacidade antioxidante, determinada pelos métodos de redução do íon férrico (FRAP) e captura do radical catiônico ABTS+0 (TEAC). Os resultados mostraram que a adição de maltodextrina contribuiu significativamente para obtenção de partículas com menor umidade e higroscopicidade e maiores tamanhos de partícula e densidade aparente. Além disso, quanto maior foi a concentração de maltodextrina adicionada, maiores foram os valores de capacidade antioxidante, provavelmente devido à formação de compostos de Maillard durante a secagem
Abstract: The objetive of the present work was to obtain a shark skin protein hydrolysate powder by enzymatic hydrolysis and spray drying. In the first part of this work was studied the enzymatic hydrolysis process by using the commercial enzyme ProtamexTM, aiming the process optimization for recovery of low molecular weight peptides. The influence of temperature, pH and Enzyme/Substrate ratio on the degree of hydrolysis, protein recovery and enzymatic kinetics was evaluated. Optimal conditions were established at: 51°C, 4.0% p/p of enzyme and pH of 7.1. At these conditions, protein hydrolysate was characterized with respect to chemical composition, amino acid composition and peptide size distribution. Degree of hydrolysis achieved 19.3%, 90.3% of total protein was recovered and peptide size was lower than 6,5 kDa. In the second part of the project, the influence of spray drying variables process on physicochemical and antioxidant properties of shark skin protein hydrolysate powders, using maltodextrin (DE=10) as a carrier agent, was evaluated. Air temperature and maltodextrin concentration were varied. The responses analyzed were the final moisture content, water activity, bulk density, hygroscopicity, particle size distribution and antioxidant capacity determined by ferric reduction antioxidant power (FRAP) and ABTS+0 radical cation capture (TEAC) assays. Results showed that maltodextrin addition significantly contributed to obtaining particles with less moisture content, lower hygroscopicity and higher particle size and bulk density. Besides, antioxidant capacity was increased as increasing of maltodextrin concentration, probably due to the formation of Maillard compounds during drying process
Mestrado
Mestre em Engenharia de Alimentos

Com o objetivo de avaliar o processo de secagem da glândula mamária de vacas da raça Holandesa foram examinadas 44 mamas na fase final da lactação, durante a evolução do processo de secagem (dia da última ordenha; 1º, 3º, 5º, 7º, 10º, 15º, 30º e 45º dia do período seco), assim como no retorno à lactação. Antes da colheita das amostras, a glândula mamária era submetida a minucioso exame clínico por inspeção e palpação, sendo complementado pela avaliação do aspecto da secreção láctea. Após os primeiros jatos da secreção terem sido desprezados, procedia-se a sua colheita asséptica, para ser utilizada no exame microbiológico, seguida da colheita das amostras destinadas à avaliação das seguintes características físico-químicas e celulares: pH, eletrocondutividade, cloretos, lactose, gordura, proteína, sólidos totais, cálculo do índice cloreto/lactose, California Mastitis Test - CMT e do número de células somáticas. O processo de secagem determinou alterações na consistência da mama, pois no retorno da lactação a freqüência de glândulas classificadas como sendo do Tipo III (firme) foi maior do que a observada antes do início da secagem e no 45ºdia do período seco, e, favoreceu a recuperação dos tetos nos quais era perceptível a presença de prolapso de pequena severidade do orifício do teto, em contrapartida, o processo de secagem não influenciou na recuperação de prolapsos considerados de grande severidade, levando a conclusão que este grau de prolapso torna-se irreversível, mesmo após longos períodos sem ordenha. Numa fase inicial do processo de secagem, a abrupta retenção do leite determinou o aumento do grau de distensão da mama e dos tetos, sendo que, durante a primeira semana, observou-se uma gradual diminuição desta distensão e, a partir do 10° dia do período seco, verificou-se o aumento progressivo na freqüência de mamas e tetos não distendidos, nas quais o processo de involução havia chegado ao seu final. No decorrer do processo de involução constatou-se que o leite foi substituído por uma secreção aquosa de coloração branca ou creme clara; sendo que a partir do 7º dia, também foi observada a presença de secreção com aspecto viscoso de coloração amarelada; ao final do processo, no 45º dia do período seco, observou-se em 40,9 % das mamas uma secreção pré-colostral, com aspecto de mel ou soro lácteo. Durante o período seco, em animais, nos quais a supressão da ordenha tenha ocorrido há mais de três dias, foram observadas alterações similares àquelas descritas nas mamites diagnosticas durante a lactação ou nas retenções de leite, ou seja, observou-se um aumento abrupto dos valores do pH, eletrocondutividade, cloretos, índice cloretos/lactose, proteína e número de células somáticas, enquanto os teores lácteos de lactose diminuíram abruptamente. Entre o 3º e o 45º dia do período seco foram obtidos os seguintes valores para as características físico-químicas e celulares da secreção láctea de vacas sadias: pH entre 7,08 e 7,34; Eletrocondutividade entre 7,50 e 8,35 mS/cm; Cloretos entre 242,20 e 287,66 mg/dl; Lactose entre 1,20 e 2,45 g/dl; Índice Cloretos/Lactose entre 12,99 e 26,40; Gordura entre 2,27 ± 7,97 g/dl; Proteína entre 6,00 e 9,47 g/dl; Sólidos Totais entre 10,73 e 16,35 g/dl; Número de Células Somáticas entre 1.930.450 e 6.486.900 células/ml. A partir do 5º dia do período seco nenhuma das amostras apresentou reações negativas ao CMT e entre o 7º e o 45º dia todas as amostras apresentavam reações do CMT classificadas como duas ou três cruzes. A avaliação da influência da ocorrência de mamite durante o processo de secagem nas características físico-químicas e celulares da secreção láctea demonstrou ser ela parcial e restrita a alguns momentos do período seco, sendo que as diferenças entre os valores obtidos no grupo de mamas com mamite e no grupo com mamas sadias eram de pequena magnitude, impedindo o diagnóstico baseado na avaliação dos resultados obtidos nas características físico-químicas e celulares da secreção láctea.Entre a última ordenha antes do seu início e o 45ºdia do período seco não houve diferenças estatísticas entre as freqüências de isolamentos bacterianos, enquanto o percentual de mamas com isolamento bacteriano no retorno da lactação foi menor do que o encontrado durante o processo de secagem da glândula mamária.
In order to evaluate the involution of the mammary gland of Holstein cows, we examined 44 udders at the end of lactation, during the dry period (last milking, and days 1, 3, 5, 7, 10, 15, 30 and 45 of the dry period), as well as the return to lactation. The mammary glands were thoroughly examined by inspection and palpation before the collection of samples. The lacteal secretion was also inspected. After discarding the first jets of the lacteal secretion, the samples for the microbiological analysis were aseptically collected, followed by the samples for the evaluation of the physicochemical and cellular characteristics - pH, electrical conductivity, chlorides, lactose, fat, protein, total solids, chloride/lactose ratio, California Mastitis Test (CMT) and somatic cell count. The involution process was accompanied by alterations in the consistency of the udder. On the return to lactation, the frequency of udders that were classified as Type III (firm) was higher than that observed before the beginning and on the 45th day of the dry period. The involution process also favored the recovery of the teats, but it did not have any effect over severe prolapses of the teat orifices, leading us to the conclusion that severe prolapses are irreversible, even after long periods without milking. On the initial phase of the dry period, the sudden retention of milk caused a distension, of the udder and of the teats, that gradually decreased along the first week. After the 10th day of the dry period, there was an increase in the number of udders and teats that were no longer distended, indicating that the involution process had ended. Along the process of involution of the mammary gland, we observed that the milk was replaced by a white or cream colored secretion; from the 7th day, a viscous and yellowish secretion was also observed; at the end of the process, on the 45th day, we observed that 40.9% of the udders were producing a pre-colostrum secretion that looked like honey or whey. During the dry period, after the 3rd day of the cessation of lactation, the cows had alterations consistent with those observed in mastitis during lactation or milk retentions. There was a sudden increase in pH, in electrical conductivity, in chlorides, in the chloride/lactose ratio, in protein and in the somatic cell count, as well as a sudden decrease in the lactose content. We observed the following values for the physicochemical and cellular characteristics of the lacteal secretion of healthy cows between the 3rd and the 45th day of the dry period: pH - between 7.08 and 7.34; Electrical Conductivity - between 7.50 and 8.35 mS/cm; Chloride - between 242.20 and 287.66 mg/dl; Lactose - between 1.20 and 2.45 g/dl; Chloride/Lactose Ratio - between 12.99 and 26.40; Fat - between 2.27 and 7.97 g/dl; Protein - between 6.00 and 9.47 g/dl; Total Solids - between 10.73 and 16.35 g/dl; Somatic Cell Count - between 1,930,450 and 6,486,900 cells/ml. From the 5th day of the dry period, none of the samples had negative reactions to the CMT; and between the 7th and the 45th day, all samples had a distinct positive or a strong positive reaction to the CMT. The influence of mastitis during the involution of the udder over the physicochemical and cellular characteristics of the lacteal secretion was partial and restricted to certain moments of the dry period. The differences between the values of these characteristics in udders with or without mastitis, was very small, so these analyses can not be used to diagnose mastitis. There was no statistical difference between the frequency of bacteria isolated from the last milking and from the 45th day of the dry period. The percentage of bacteria isolated from the udders was lower on the return to lactation than during the involution of the mammary gland.

FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico
O presente trabalho teve como objetivo avaliar os parÃmetros fÃsico-quÃmicos e quÃmicos e a atividade da polifenoloxidase (PPO) e peroxidase (POD) nas etapas de processamento e durante a vida de prateleira do suco tropical de manga nÃo adoÃado envasado pelo processo hot fill. Foram retiradas amostras apÃs as etapas de despolpa, homogeneizaÃÃo e pasteurizaÃÃo e do produto logo apÃs o processamento e aos 55, 110 e 165 dias de armazenamento (28ÂC Â 2ÂC). A acidez total titulÃvel, pH, sÃlidos solÃveis totais (ÂBrix), aÃÃcares redutores e totais, Ãcido ascÃrbico, carotenÃides, antocianinas e cor (L*, a* e b*) foram analisados. Os resultados apresentaram que o pH, a acidez total titulÃvel, o conteÃdo de aÃÃcar total e carotenÃides nÃo apresentaram significÃncia estatÃstica ao nÃvel de 5% durante o perÃodo de armazenagem. Foi observada uma maior atividade da PPO durante as etapas de processamento estudadas bem como na vida de prateleira do produto, de um modo geral mantendo-se oscilante. A POD apresentou atividade crescente nas etapas de processamento e em seguida mantendo-se constante durante o armazenamento. Conclui-se que os parÃmetros fÃsico-quÃmicos e quÃmicos para esse produto encontram-se dentro dos limites estabelecidos pela LegislaÃÃo Brasileira e o tratamento tÃrmico nÃo se apresentou eficiente para a inativaÃÃo dessas enzimas, devido possivelmente a presenÃa de isoformas com diferentes graus de termoestabilidade e/ou renaturaÃÃo de isotipos.
O presente trabalho teve como objetivo avaliar os parÃmetros fÃsico-quÃmicos e quÃmicos e a atividade da polifenoloxidase (PPO) e peroxidase (POD) nas etapas de processamento e durante a vida de prateleira do suco tropical de manga nÃo adoÃado envasado pelo processo hot fill. Foram retiradas amostras apÃs as etapas de despolpa, homogeneizaÃÃo e pasteurizaÃÃo e do produto logo apÃs o processamento e aos 55, 110 e 165 dias de armazenamento (28ÂC Â 2ÂC). A acidez total titulÃvel, pH, sÃlidos solÃveis totais (ÂBrix), aÃÃcares redutores e totais, Ãcido ascÃrbico, carotenÃides, antocianinas e cor (L*, a* e b*) foram analisados. Os resultados apresentaram que o pH, a acidez total titulÃvel, o conteÃdo de aÃÃcar total e carotenÃides nÃo apresentaram significÃncia estatÃstica ao nÃvel de 5% durante o perÃodo de armazenagem. Foi observada uma maior atividade da PPO durante as etapas de processamento estudadas bem como na vida de prateleira do produto, de um modo geral mantendo-se oscilante. A POD apresentou atividade crescente nas etapas de processamento e em seguida mantendo-se constante durante o armazenamento. Conclui-se que os parÃmetros fÃsico-quÃmicos e quÃmicos para esse produto encontram-se dentro dos limites estabelecidos pela LegislaÃÃo Brasileira e o tratamento tÃrmico nÃo se apresentou eficiente para a inativaÃÃo dessas enzimas, devido possivelmente a presenÃa de isoformas com diferentes graus de termoestabilidade e/ou renaturaÃÃo de isotipos.
The present work aimed to evaluate the physicochemical and chemical parameters and polyphenoloxidase (PPO) and peroxidase (POD) activity on the processing stages and shelf life of the tropical non sweetened mango juice preserved by hot fill method. The samples were removed afterwards the pulp discharged, homogenation, pasteurization and the product in the end of the processing and after 55, 110 and 165 days of storage (28ÂC Â 2ÂC). Total titratable acidity, pH, total soluble solids (ÂBrix), reducing and total sugar, ascorbic acid, carotenoids, anthocyanins and colour (L*, a* e b*) were analysed. The results showed that pH, total titratable acidity, total sugar content and carotenoids not have a statistical significance at a level of 5% along the storage time. It was observed a higher PPO activity during the studied processing stages and in the shelf life of the product, keeping oscillating in a general manner. The POD showed an increasing activity during the processing stages and keeping stable along the storage. In conclusion the physicochemical and chemical parameters for this product were within the limits established by the Brazilian legislation and the thermal treatment was not efficient to inactivate these enzymes probably due to the possible presence of isoforms with different thermo stability grades and/or isotypes renaturation.
The present work aimed to evaluate the physicochemical and chemical parameters and polyphenoloxidase (PPO) and peroxidase (POD) activity on the processing stages and shelf life of the tropical non sweetened mango juice preserved by hot fill method. The samples were removed afterwards the pulp discharged, homogenation, pasteurization and the product in the end of the processing and after 55, 110 and 165 days of storage (28ÂC Â 2ÂC). Total titratable acidity, pH, total soluble solids (ÂBrix), reducing and total sugar, ascorbic acid, carotenoids, anthocyanins and colour (L*, a* e b*) were analysed. The results showed that pH, total titratable acidity, total sugar content and carotenoids not have a statistical significance at a level of 5% along the storage time. It was observed a higher PPO activity during the studied processing stages and in the shelf life of the product, keeping oscillating in a general manner. The POD showed an increasing activity during the processing stages and keeping stable along the storage. In conclusion the physicochemical and chemical parameters for this product were within the limits established by the Brazilian legislation and the thermal treatment was not efficient to inactivate these enzymes probably due to the possible presence of isoforms with different thermo stability grades and/or isotypes renaturation.

OLIVEIRA, Aurelice Barbosa de. Caracterização físico-química, química e bioquímica do suco tropical de manga (Mangifera indica L.) não adoçado obtido pelo processo hot fill. 2006. 110 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências Agrárias, Departamento de Tecnologia de Alimentos, Fortaleza-Ce, 2006
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The present work aimed to evaluate the physicochemical and chemical parameters and polyphenoloxidase (PPO) and peroxidase (POD) activity on the processing stages and shelf life of the tropical non sweetened mango juice preserved by hot fill method. The samples were removed afterwards the pulp discharged, homogenation, pasteurization and the product in the end of the processing and after 55, 110 and 165 days of storage (28ºC ± 2ºC). Total titratable acidity, pH, total soluble solids (ºBrix), reducing and total sugar, ascorbic acid, carotenoids, anthocyanins and colour (L*, a* e b*) were analysed. The results showed that pH, total titratable acidity, total sugar content and carotenoids not have a statistical significance at a level of 5% along the storage time. It was observed a higher PPO activity during the studied processing stages and in the shelf life of the product, keeping oscillating in a general manner. The POD showed an increasing activity during the processing stages and keeping stable along the storage. In conclusion the physicochemical and chemical parameters for this product were within the limits established by the Brazilian legislation and the thermal treatment was not efficient to inactivate these enzymes probably due to the possible presence of isoforms with different thermo stability grades and/or isotypes renaturation.
O presente trabalho teve como objetivo avaliar os parâmetros físico-químicos e químicos e a atividade da polifenoloxidase (PPO) e peroxidase (POD) nas etapas de processamento e durante a vida de prateleira do suco tropical de manga não adoçado envasado pelo processo hot fill. Foram retiradas amostras após as etapas de despolpa, homogeneização e pasteurização e do produto logo após o processamento e aos 55, 110 e 165 dias de armazenamento (28ºC ± 2ºC). A acidez total titulável, pH, sólidos solúveis totais (ºBrix), açúcares redutores e totais, ácido ascórbico, carotenóides, antocianinas e cor (L*, a* e b*) foram analisados. Os resultados apresentaram que o pH, a acidez total titulável, o conteúdo de açúcar total e carotenóides não apresentaram significância estatística ao nível de 5% durante o período de armazenagem. Foi observada uma maior atividade da PPO durante as etapas de processamento estudadas bem como na vida de prateleira do produto, de um modo geral mantendo-se oscilante. A POD apresentou atividade crescente nas etapas de processamento e em seguida mantendo-se constante durante o armazenamento. Conclui-se que os parâmetros físico-químicos e químicos para esse produto encontram-se dentro dos limites estabelecidos pela Legislação Brasileira e o tratamento térmico não se apresentou eficiente para a inativação dessas enzimas, devido possivelmente a presença de isoformas com diferentes graus de termoestabilidade e/ou renaturação de isotipos.

碩士
國立宜蘭大學
化學工程與材料工程學系碩士班
107
In Taiwan, large quantity of agricultural waste was produced every year. These agricultural waste which were most as biomass, for example, rice straw, was rich with lignocellulose. This study investigated the physicochemical characteristics of agricultural waste by different reaction condition including change in temperature, pressure and reaction time under torrefaction process. The test items of physicochemical characteristics including approximate analysis, elemental analysis, torrefaction weight loss, thermogravimetric analysis, lignocellulose content measuring, Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscope/Energy-dispersive X-ray spectroscopy (SEM/EDX). As the results showed from the study, rise in temperature caused the most change of physicochemical characteristics compared with raw rice straw. Under the maximum temperature condition of torrefaction, 325oC-20Kg/cm2-60min, the approximate analysis of torrefaction product showed that the moisture content and volatile content reduced by 5.8459% and 33.2701%. Ash content, carbon fixation content and heat value rose in 16.4851%, 22.6308% and 1853.5643cal/g, respectively. In elemental analysis of torrefaction product showed that the C elemental contant rose in 11.332%, O and H elemental contant reduced by 28.173% and 1.653%, respectively. The torrefaction weight loss rate reached 53.2307%. In lignocellulose content measuring of torrefaction product showed that the hemicellulose and cellulose contant reduced by 43.7533% and 26.3270%, the lignin content roce in 53.3837%, respectively. The results from FTIR showed that there are some functional group in raw rice straw such as C-H, O-H, C-O and C=O. The surface structure, showed from SEM/EDX, was changed because hemicellulose and cellulose were pyrolysis. As the results showed from this study, physicochemical characteristics of rice straw was changed significantly under torrefaction process.

碩士
國立高雄餐旅大學
餐飲創新研發碩士學位學程
100
The ripening classification defines 7 stages by color index, the higher stage stands for higher ripeness. In this study, bananas were ripened at 20 ℃, 90% RH for 20 days to evaluate the effects of ripening on firmness, polyphenol oxidase activity, peroxidase activity, total phenolic contents and DPPH free radical scavenging ability. Results showed that the firmness decreased and total soluble solid contents increased during ripening periods. Polyphenol oxidase activity increased from 1st stage of 0.04 U/g.fw to 7th stage of 2.31 U/g.fw, and peroxidase activity increased from 1st stage of 0.04 U/g.fw to 7th stage of 1.90 U/g.fw. The increasing of enzyme activity illustrated that bananas caused enzymatic Maillard reaction easier during ripening. With respect to antioxidative activity, the IC50 value of DPPH free radical scavenging ability decreased from 1st stage of 116.97 mg/mL to 6th stage of 51.46 mg/mL, and this stage with best antioxidative activity. Regarding to the physicochemical analysis of the steam-heated banana puree, the residual activity of PPO was 2.70% and the residual activity of POD was 4.17% , also the banana center temperature reached to 83℃ after banana heating for 8min. Furthermore, the residual activity of PPO was 0.9% and the residual activityof POD was 0% , also the banana center temperature reached to 87℃ after banana heating for 10min. Both enzyme activity was inhibited so the banana b value (yellowness), θvalue (hue angle) and C values (chroma) were higher after steam heating treatment. Compared with commercial banana puree, our puree showed more bright yellow in appearance color. The banana puree that steam-heated for 8min, reserved more banana aroma and flavor and suited for banana filling processing. Adding sugar increased the chroma value, total soluble solids, and decreased water activity. When added 40% sugar, pH value of banana filling was 4.92 and the water activity decreased from 0.934 to 0.591. It’s appearance showed bright yellow and full of aroma. In our studies, banana cakes adding 40% sugar and 0.4% citric acid showed highest overall acceptability.

Yes
Objectives  In this work we investigated the residual organic solvent content and physicochemical properties of spray-dried chlorothiazide sodium (CTZNa) and potassium (CTZK) salts. Methods  The powders were characterised by thermal, X-ray diffraction, infrared and dynamic vapour sorption (DVS) analyses. Solvent levels were investigated by Karl–Fischer titration and gas chromatography. Key findings  Spray-drying from water, methanol (MeOH) and mixes of MeOH and butyl acetate (BA) resulted in amorphous microparticles. The glass transition temperatures of CTZNa and CTZK were ∼192 and ∼159°C, respectively. These materials retained their amorphous nature when stored at 25°C in dry conditions for at least 6 months with no chemical decomposition observed. DVS determined the critical relative humidity of recrystallisation of CTZNa and CTZK to be 57% RH and 58% RH, respectively. The inlet temperature dependant oxidation of MeOH to formaldehyde was observed; the formaldehyde was seen to deposit within the amorphous matrix of spray-dried product. Spray-drying in the open blowing mode coupled with secondary drying resulted in a three-fold reduction in residual BA (below pharmacopoeial permitted daily exposure limit) compared to spray-drying in the closed mode. Conclusions  Experiments showed that recirculation of recovered drying gas increases the risk of deposition of residual solvents in the spray-dried product.
The Irish Research Council for Science and Engineering Technology (IRCSET), the Solid State Pharmaceutical Cluster (SSPC), supported by Science Foundation Ireland under grant number (07/SRC/B1158) and the Irish Drug Delivery Research Network, a Strategic Research Cluster grant (07/SRC/B1154) under the National Development Plan co-funded by EU Structural Funds and Science Foundation Ireland.

Thesis (Ph.D.)--University of Alberta, 2010.
Title from PDF file main screen (viewed on July 29, 2010). A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Bioresource and Food Engineering, Department of Agricultural, Food and Nutritional Science, University of Alberta. Includes bibliographical references.

碩士
國立屏東科技大學
食品科學系所
97
We anticipate using extrusion technology to develop a functional snack food by adding water chestnut powder in the process of extrusions. The process variables including feed moisture content were set at 15% and 18% and the process including feed composition of brown rice powder and water chestnut powder (100:0, 90:10, 80:20, 70:30, 60:40, 50:50 and 0:100) and different particle sizes (14-30 and 30-50 mesh). The effects of moisture content, moisture retention, water activity, color, water absorption index, water solubility index and resistant starch content of extrudates were investigated in this study. The results indicated when the feed moisture content was at 18% either the particle size of 14-30 or 30-50 mesh gained highest extrudate moisture content, water activity and resistant starch content. When particle size was in the range of 14-30 mesh and feed moisture content was at 15%, produced highest moisture retention and L value except the group with feed composition of 60:40. When particle size was at 30-50 mesh and feed moisture content was at 18%, gained highest moisture retention and L value. The feed moisture content was at 15%, feed composition was at 60:40 and 50:50 and the particle size was at 14-30 mesh produced highest a value, the rest gained greater a value when feed moisture content was set at 18%. The feed moisture content of 15% produced highest a value when the particle size is 30-50 mesh. When the particle size was at 14-30 mesh and the feed moisture content was at 18%, produced greater b value. Changing the particle size to 30-50 mesh, the group with feed moisture content of 15% gained higher b value. The water absorption index showed highest when the particle size was at 14-30 mesh, feed composition was at 80:20 and the feed moisture content was set at 18%. The rests were gained greatest b value at the 15% of feed moisture content. The water absorption index also showed greater when particle size was at 30-50 mesh, feed composition were at 90:10, 70:30, 60:40 and the feed moisture content was at 15%. When particle size was 14-30 mesh, feed moisture content was at 18% produced higher water solubility index. When particle size was at 30-50 mesh, feed composition were 60:40 and 50:50 and the feed moisture content was 15%, produced highest water solubility index.

碩士
國立中興大學
食品暨應用生物科技學系所
99
Instant rice flour belongs to the pregelatinized cereal products group and mainly uses the dry methods: puffing, roasting or wet methods: drum drying, steaming or extrution to carry out gelatinization, drying, grinding, sieving to obtain the cereal particles and paste. The puffing gun and drum dryer are often used to produce edible cereal products because of their low costs and easy to use. This study uses puffing and drum drying to prepare instant rice flour and examines the effects of (1) different puffing pressures (0, 3, 5, 7, 9, 11kg/cm2), (2) cold and hot slurry feed, (3) different surface temperatures, (4) amylase content of rice (TCN1, TK9 and TCW70) on the physicochemical properties, rehydration properties and product turbidity stability; and multiple regression analysis was used to set up math models of the processing effect parameter of puffing and drum drying, absorbent index, and solubility. Moreover, modify the quality of instant rice flour by adding gums and puffed TCW70 -11 kg / cm2. The results show that the WAI, WSI, SP, degree of gelatinization, dextrin content, separation ratio and turbidity stability of puffed instant rice flour increase with the puffing pressure rises, but particle size and molecular weight decrease. The products’ hydration preperties and separation ratio can be estimated by three math model: WAI = 8.00100－0.233223×A+ 0.014585×T+ 0.0288663×P (r 2=0.87), SP = 10.70046－0.42053×A+ 0.04572×T+0.40982×P (r 2=0.84), WSI = 7.514986－0.821779×A +0.131696×T +1.730803×P (r 2=0.87) and separation ratio = 0.538692-0.020034×A + 0.002299 T+0.049799×P (r 2=0.89). Multiple-porous structures and completed gelatinization are found in drum dried instant rice flour, and it’s WSI, dextrin, turbidity stability and separation ratio increase with surface temperature increase. The hydration preperties and separation ratio of drum dried instant rice flour also can be estimated by math modle, respectively: cold slurry feeded could be used by WAI = 9.861863－0.334415A +0.087127T+0.039369TS (r2=0.87), SP = 1.101079－0.481397A +0.199154T+0.106375TS (r2=0.95) and separation ratio = 0.562169-0.019469A+0.000952T+0.003206Ts(r2= 0.94); Hot slurry feeded could be used by WSI=53.87873－2.61321A+ 0.21491T+0.09996TS (r2= 0.99) and separation ratio =0.230230- 0.014633A+ 0.001675T+0.005635Ts (r2= 0.88). There are good separation stability, turbidity stability and most popular overall acceptance when puffed instant rice flour is modified by adding 0.2 % guan gum and drum dried instant rice flour is modified by adding 2 % puffed TCW70 -11 kg / cm2 flour.

碩士
國立高雄海洋科技大學
水產食品科學研究所
102
Orang (Citrus sinensis L. cv.) and calamondin (Citrus microcarpa Bonge) are important agricultural crops in Taiwan. After processing, a great quantity of pomace was produced. Pomace is rich in dietary fiber. It is worthwhile to deeply investigate the development and utilization of the pomace by different processing. The study was to investigate the optimization of extruded pomace derived from orange and calamondin using response surface methodology. Tested extrusion variables were barrel temperature (115C, 125C, 135C), moisture contents (10, 14, 18 g/100 g) and screw speed (230, 290, 350 rpm). Soluble dietary fiber content in each treatment group serves as an evaluable index to obtain optimal conditions. Meanwhile, the effect of extrusion processing on physicochemical properties of extrudates as well as in vitro physiological tests such as glucose absorption, cholesterol micelle solubility capacity and bile acid binding capacity of extrudates were also evaluated. Finally, the use of optimal extrusion conditions would further develop a high-fiber bakery product with nutritional function, and investigate its quality. The results showed that soluble dietary fiber content of extrudates was significantly influenced by above three variables. From calculation of regression equation, it showed that optimal extrusion condition: barrel temperature, moisture content, and screw speed of extruded orange pomace is 131.6C, 16 g/100 g and 304.8 rpm, respectively; while barrel temperature, moisture content, and screw speed of extruded calamondin pomace is 128.5C, 15.6 g/100 g , 298.1 rpm, respectively. The soluble dietary fiber contents of orange and calamondin pomace were 17.3% and 24.6%, respectively before extrusion. Processing conditions increased soluble dietary fiber content up to 29.8% and 40.0%, respectively for orange pomace and calamondin pomace. These pomace processed by single extruder significantly (P < 0.05) change the physicochemical properties such as bulk density, water-retention capacity, swelling property, cation-exchange capacity, water solubility index, dispersibility, emulsification activity, and gelation property in which they had higher properties than those before extrusion. The results of In vitro experiments indicate that orange and calamondin extrudates than the cellulose and non-extruded pomaces could effectively retard glucose absorption. Orange and calamondin pomace after extrusion was found to significantly (P < 0.05) decrease the amount of intact cholesterol-micelle than those without extrusion processing. Increased addition of extruded pomace into bread formulation resulted in decreases of total area and specific volume as well as increases of cell area and hardness. The substitution of extrude pomace into bread formulation at the level of 5% significantly (P < 0.05) influences the bread color, but sensory evaluation has indicated that the bread product are acceptable to the target audience. In conclusion, oranges and calamondin pomace by extrusion processing than those without extrusion, had good physicochemical properties and physiological functions in vitro.

碩士
靜宜大學
食品營養研究所
91
The effects of xylooligosaccharides (XO) on bovine serum albumin (BSA) structure, aggregation, and surface hydrophobicitiy during heating process were investigated. BSA solution (5 and 20 mg/mL) in the presence of 0, 2, and 20% XO (w/v) were heated from 30 to 100℃ in a water bath for 20 min. Electrophoresis was used to study the composition and structure of BSA. BSA formed aggregates when heated to 60℃ and above. The amounts of aggregates were increased with protein concentration. Noncovalent bonds and disulfide bonds were predominant in the formation of the aggregates. In the case of adding 20% XO in 5mg/mL BSA solution, the amounts of oligomers were decreased as heated to 60℃. Electrophoresis and glycoprotein staining revealed the diffused monomer band and covalent linked high molecular weight aggregates resulting from XO modification. The degree of Maillard reaction was evaluated by measuring the absorption spectrum at 320nm and 420nm. When heated at 90℃ the yields of soluble pre-melanoidins and Maillard reaction products were increased significantly. Fluorescence probe (ANS) was used to determine the surface hydrophobicity of BSA. The surface hydrophobicity decreased with increasing temperature, indicating the aggregation of BSA. When heated to 60 ℃, BSA solutions (5 and 20 mg/mL) containing 20% XO showed higher surface hydrophobicity than no XO addition. These results suggested that XO could enhance the thermo-stability of BSA or prevent the unfolded BSA forming aggregates at 60℃. After heating to 90℃, BSA could be modified by XO and form covalent bound aggregates via Maillard reaction.

The microbial aggregates (flocs) formed during secondary biological treatment of wastewater shield microbes from exposure to ultraviolet (UV) light, and decrease the efficiency of disinfection, causing the tailing phenomena. This thesis investigates whether the formation of compact cores within flocs induces higher levels of UV resistance. Moreover, it investigates the effect of secondary treatment conditions on the physicochemical properties of flocs’, effluent quality, and UV disinfection performance. Compact cores were isolated from the flocs using hydrodynamic shearing. The UV dose response curves (DRC) were constructed for flocs and cores, and the 53-63 μm cores showed 0.5 log less disinfectability, compared to flocs of similar size. Based on a structural model developed for the UV disinfection of flocs, floc disinfection kinetics was sensitive to the core’s relative volume, their density, and viability. The UV disinfection and floc properties of a conventional activated sludge (CAS) system, and a biological nutrient removal (BNR-UCT) system, including both biological nitrogen and phosphorus removal, was compared. The 32-53 μm flocs and the final effluent from the BNR-UCT reactor showed 0.5 log and 1 log improvement in UV disinfectability, respectively, compared to those from the CAS reactor. The BNR-UCT flocs were more irregular in structure, and accumulated polyphosphates through enhanced biological phosphorus removal. Polyphosphates were found to be capable of producing hydroxyl radicals under UV irradiation, causing the photoreactive disinfection of microorganisms embedded within the BNR-UCT flocs, accelerating their UV disinfection. Comparing the UV disinfection performance and floc properties at various operating conditions showed that increasing the operating temperature from 12 ºC to 22 ºC, improved the UV disinfection of effluent by 0.5 log. P-Starved condition, i.e. COD:N:P of 100:10:0.03, decreased the average floc size and sphericity, both by 50%. Despite the higher effluent turbidity of the P-Starved reactor, the final effluent’s UV disinfection improved by at least 1 log compared to the P-Normal and P-Limited conditions. The improvement in the floc and effluent disinfectability were accompanied by a decrease in floc sphericity and a decrease in the number of larger flocs in the effluent, respectively.

Yes
Objectives This work investigated the impact of spray drying variables such as feedconcentration, solvent composition and the drying mode, on the micromeriticproperties of chlorothiazide sodium (CTZNa) and chlorothiazide potassium(CTZK).Methods Microparticles were prepared by spray drying and characterised usingthermal analysis, helium pycnometry, laser diffraction, specific surface area analysisand scanning electron microscopy.Key findings Microparticles produced under different process conditions pre-sented several types of morphology.To systematise the description of morphology ofmicroparticles, a novel morphology classification system was introduced. The shapeof the microparticles was described as spherical (1) or irregular (2) and the surfacewas classified as smooth (A) or crumpled (B). Three classes of morphology of micro-particles were discerned visually: class I, non-porous; classes II and III, comprisingdiffering types of porosity characteristics. The interior was categorised as solid/continuous (a), hollow (b), unknown (g) and hollow with microparticulate content(d). Nanoporous microparticles of CTZNa and CTZK, produced without recircula-tion of the drying gas, had the largest specific surface area of 72.3 and 90.2 m2/g,respectively, and presented morphology of class 1BIIIa.Conclusions Alteration of spray drying process variables, particularly solvent com-position and feed concentration can have a significant effect on the morphology ofspray dried microparticulate products. Morphology of spray dried particles may beusefully described using the morphology classification system.
The Irish Research Council for Science and Engineering Technology (IRCSET), the Solid State Pharmaceutical Cluster (SSPC), supported by Science Foundation Ireland under grant number [07/SRC/B1158] and the Irish Drug Delivery Research Network, a Strategic Research Cluster grant (07/SRC/B1154) under the National Development Plan co-funded by EU Structural Funds and Science Foundation Ireland.

碩士
輔仁大學
食品科學系碩士班
105
Hen egg is normally made into powders to extend its shelf-life. However, egg shell which contains about 94% calcium carbonate and is a good source of calcium is the major waste after processing. Fluidized bed coating is a process which sprayed the coating solution on the surface of core material, consequently, the film was formed and the core material was embedded. This process could improve the appearance and properties of powder. Combining the egg shell and egg liquid using this technology might enhance the nutritional value of egg powder and reduce the waste of egg processing. The un-fertilized soft-shell turtle eggs often use as animal feed. Therefore, powder preparation of these eggs might increase its application. This research aimed to evaluate the conditions of fully-utilized egg powders preparation using fluidized bed coating process and the physicochemical properties of these powders and investigate the effect of different coating temperature on the functional properties of fully-utilized soft-shell turtle egg powders. The egg shells were washed, dried, and ground into powders and used as the substrate. The whole egg liquid was used as the coating material. The egg powder was prepared using fluidized bed equipment. Results showed that the average yield of hen egg powder was above 40%. The water activity and moisture content of egg powders were around 0.2 and 2%, respectively. These results indicated that the prepared powders had good storage stability. The a* and b* values and solute content of powder increased, but L value decreased with increasing the feeding rate. The moisture content decreased, while the a* and b* values and solute content increased with increasing the coating temperature. The foaming capacity and fat- and water-absorption capacities of soft-shell turtle egg powder coated at 120oC were the highest. Moreover, soft-shell turtle egg powder coated at 80oC had the best emulsifying capacity and gel strength. According to the microstructure analysis, most of the egg liquid was coated evenly on the egg shell surface. The particle size increased with increasing the feeding time and rate. In conclusion, the preparation of fully-utilized egg powders using fluidized-bed equipment was successful. The fully-utilized soft shell turtle egg powder prepared with different coating temperature had different functional properties.