Dissertations / Theses: 'Vegetable oils and fats'

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Cash, Gregory Anthony. "Studies of the oxidation and stabilisation of vegetable oils and model compounds." Thesis, Queensland University of Technology, 1986. https://eprints.qut.edu.au/35985/1/35985_Cash_1986.pdf.

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This thesis describes the use of a novel chemiluminescence (CL) technique to deter·mine the extent of oxidation and stability in both model compounds and vegetable oils. As it is the presence of hydroperoxides in vegetable oils that leads to theirdeterioration, the hydroperoxides of methyl linoleate (MU were used as model compounds in a CL study of hydroperoxide decomposition in nitrogen, both in the bulk and on active substrates. The largest signals and the fastest decays occurred on neutral alumina. The results indicate induced decomposition via a bimolecular initiation of hydroperoxides adsorbed on adjacent active sites. The majority of these hydroperoxides are vertical to the surface, being bound to the alumina through the ester group only. A relationship was found between hydroperoxide concentr·ation and initial intensity when the methyl linoleate hydroperoxide was adsorbed on neutral alumina. Solutions of natural and arti-ficial antioxidants in ML were studied. Some solutions gave changes in kinetics. These changes suggest that the antioxidant itself may contribute to the CL. The method of inhibitors was used to find the rate of initiation and hydroperoxide level in ML at 80c:>C. The spectral distribution of CL was determined for model compounds, antioxidants and vegetable oils. In the presence of antioxidants ther-e was a shift towar-d the r-ed end of the spectr-um. In model compounds, the CL was most likely due to an excited triplet state ketone and this is consistent with the mechanism for- ter·mination of alkyl peroxy r-adicals. The techniques developed for the model compounds were extended to the mor-e complex vegetable oils. Unrefined and deliberately damaged vegetable oils were studied at 80c:>C on neutral alumina. CL examination of these oils in nitr-ogen was able to distinguish between some damaged and undamaged oils. Conjugated diene levels did not correlate well with CL results. 0<-tocopherol and a-carotene were found to be chemiluminescent on alumina and their presence in unr·efined oil may inter·fer·e with CL assessment. The method of inhibitors, when applied to a vegetable oil sample, permitted the determination of both hydroperoxide concentration and the level of natural antioxidant alr-eady present in the oil. ii

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Kupranycz, Donna B. (Donna Bohdanka). "Effects of thermal oxidation on the constitution of butterfat, butterfat fractions and certain vegetable oils." Thesis, McGill University, 1986. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=72822.

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Retief, Liezel. "Analysis of vegetable oils, seeds and beans by TGA and NMR spectroscopy." Thesis, Stellenbosch : University of Stellenbosch, 2011. http://hdl.handle.net/10019.1/6831.

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Thesis (PhD (Chemistry and Polymer Science))--University of Stellenbosch, 2011. ENGLISH ABSTRACT: Due to the commercial, nutritional and health value of vegetable oils, seeds and beans, the analysis of their components is of much interest. In this dissertation oil-containing food products, specifically vegetable oils, seeds and beans, were investigated. Selected minor components of three locally produced vegetable oils, namely apricot kernel, avocado pear and macadamia nut oils were investigated using 31P NMR spectroscopy. These minor components, including 1,2 diacylglycerols, 1,3 diacylglycerols and free fatty acids, were identified in the 31P NMR spectra of each of the three vegetable oils for the first time. Two approaches were used for the quantification of the minor components present in the spectra. A calibration curve approach used known concentrations of standard minor components to establish calibration curves while a direct correlation approach calculated the unknown concentration of minor components in the vegetable oils using a known amount of standard compound within the analysis solution. These approaches aided in determining the concentration of minor components during storage studies in which vegetable oils were stored in five different ways: exposed to light, in a cupboard, in a cupboard wrapped in tin foil, at -8 °C and at 5 °C. It was found that determining the best storage condition for each oil was difficult since individual minor components were affected differently by the various storage conditions. However, in general the best storage conditions appeared to be 5 °C and -8 °C. The oil, protein and carbohydrate contents of sesame, sunflower, poppy, and pumpkin seeds, and soy, mung, black and kidney beans were analysed by thermogravimetric analysis and 13C NMR solid state NMR spectroscopy. It was shown that the first derivative of TGA data for seeds and beans can give valuable information about the carbohydrate, moisture, protein and fat content. This has not been previously demonstrated. For the seeds, the integration of a region between 270–480 ºC was equal to the sum of the oil and protein content and compared well to quantitative results obtained by other conventional methods. For beans the integration of a region between 180-590 ºC, gave a value which represented the sum of the oil, protein and carbohydrate content. 13C solid state NMR spectroscopy, including SPE-MAS, CP-MAS and variable contact time experiments, was carried out on these seeds and beans and gave valuable information on the solid-like and liquid-like components. To our knowledge these seeds and beans have never been previously analysed using this technique. 13C SPE-MAS NMR spectroscopy indicated that the seeds contained more liquid-like components than the beans. In turn the 13C CP-MAS NMR spectra indicated that beans had higher levels of solid-like components than the seeds. These conclusions correlated well with the quantities of liquid-like components and solid-like components that were determined by conventional methods and TGA. Preliminary studies using T1pH experiments on the components present in the seeds and beans led to a few observations. Most interesting is that a model using a two- phase fit in order to determine T1pH values appears to be more accurate than a one-phase model. AFRIKAANSE OPSOMMING: Groente olies, sade en bone is ‘n onderwerp van groot belang omrede hul kommersiële, voeding en gesondheidswaardes. In hierdie tesis is olie-bevattende voedselprodukte, spesifiek groente-olies, sade en bone geanaliseer. Geselekteerde komponente teenwoordig in klein hoeveelhede in drie lokaal geproduseerde groente-olies, naamlik appelkoos-pit, avokadopeer en makadamia-neut olies is geanaliseer met behulp van 31P KMR spektroskopie. Hierdie komponente, insluitend 1,2 diasielglyserole, 1,3 diasielglyserole en ongebonde vetsure, is vir die eerste keer geïdentifiseer in die 31P KMR spektra van die drie groente olies. Twee benaderings is gebruik vir die hoeveelheids-bepaling van die komponente in die spektra. ‘n Yking-kurwe metode het gebruik gemaak van bekende hoeveelhede konsentrasies standaard komponente vir die opstel van yking-kurwes, terwyl ‘n direkte korrelasie metode gebruik is om die onbekende konsentrasie van komponente in groente olies te bepaal met behulp van ‘n bekende hoeveelheid standaard verbinding teenwoordig in die oplossing. Hierdie metodes het gelei tot die bepaling van die konsentrasies van die komponente gedurende vyf verskillende berging toestande wat ingesluit het: Blootgestel aan lig, in ‘n donker kas, in ‘n donker kas toegevou in tin foelie, bevries by -8 °C en in ’n koelkas by 5 °C. Dit was bevind dat bepaling van die beste bergingstoestand vir elke olie moeilik is aangesien die individuele komponente verskillend geaffekteer word deur die verskeie berging toestande. Die beste bergings toestand oor die algemeen blyk egter om by 5 °C en -8 °C te wees. Sesamsaad, sonneblomsaad, papawersaad en pampoensaad sowel as sojaboontjie, mungboontjie, swartboontjie en pronkboontjie se olie, protein en koolhidraat komponente was geanaliseer met behulp van termogravimetriese analise (TGA) en 13C soliede toestand KMR spektroskopie. Dit was bevind dat die eerste afgeleide van die TGA data waardevolle inligting lewer oor die komponent inhoud van elk van die sade en bone. Hierdie is nog nie vantevore bevind nie. Vir die sade, was die integrasie van ‘n area tussen 270–480 ºC gelyk aan die som van die olie en proteïen inhoud en het goed vergelyk met die waardes verky deur algemene analitiese metodes. Vir die boontjies, was die integrasie van ‘n area tussen 180-590 ºC gelyk aan die som van die olie, protein en koolhidraat inhoud. 13C vaste staat KMR spektroskopie, insluitende SPE-MAS, CP-MAS en variëerbare kontak-tyd eksperimente, was gedoen en het waardevolle inligting gelewer omtrent die solied-agtige en mobiel-agtige komponente. Hierdie sade en bone is tot ons kennis nog nie van te vore met die tegnieke ondersoek nie. 13C SPE-MAS NMR spektroskopie het aangedui dat daar ‘n groter hoeveelheid mobiel-agtige komponente in sade as in bone teenwoordig is. 13C CP-MAS NMR spektroskopie het weer aangedui dat daar ‘n groter hoeveelheid solied-agtige komponente in bone as in sade teenwoordig is. Hierdie gevolgtrekkings het goed vergelyk met die waarnemings verkry deur konvensionele analitiese metodes en TGA. Voorlopige studies op die komponente van sade en bone deur T1pH eksperimente het tot ‘n paar gevolgtrekkings gelei waarvan die mees interessantste was dat ‘n twee-fase model vir die bepaling van T1pH waardes beter resultate lewer as ‘n een-fase model.

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Belting, Patrícia Castro 1977. "Vapor liquid phase equilibrium in the vegetable oil industry = Equilíbrio líquido vapor na indústria de óleos vegetais." [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/255089.

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Orientadores: Antonio José de Almeida Meirelles, Jürgen Gmehling Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos Made available in DSpace on 2018-08-23T15:44:16Z (GMT). No. of bitstreams: 1 Belting_PatriciaCastro_D.pdf: 4041052 bytes, checksum: 985b093f692b3bc9a1072474787582f8 (MD5) Previous issue date: 2013 Resumo: Propriedades termodinâmicas são úteis para a realização de projetos confiáveis, otimização e modelagem de processos que envolvam separação térmica e para a seleção de solventes usados em processos de extração. Tais propriedades são também necessárias no desenvolvimento de novos modelos termodinâmicos e no ajuste de parâmetros de modelos preditivos. Este trabalho de tese teve como objetivo principal ampliar o banco de dados de propriedades termodinâmicas para compostos graxos através da determinação sistemática do coeficiente de atividade à diluição infinita ( ), entalpia de excesso ( ) e dados de equilíbrio líquido-vapor (ELV) de sistemas contendo ácidos graxos e óleos vegetais. A primeira parte deste trabalho apresenta os dados de para vários solutos orgânicos diluídos em ácidos graxos saturados e insaturados, medidos pelo método de cromatografia gás-líquido na faixa de temperatura entre 303,13 K e 368,19 K. Através dos resultados obtidos, puderam ser identificadas diferentes tendências para compostos polares e não polares, tanto na série de ácidos graxos como também em relação à temperatura. Foi verificado que tanto a presença quanto o número de insaturações na cadeia carbônica do ácido graxo têm influência nas interações solvente-soluto e, consequentemente, nos valores de . A segunda parte deste trabalho tratou de medidas realizadas em sistemas contendo óleos vegetais refinados. Os óleos de soja, girassol e canola foram submetidos a determinações de , e ELV. As medidas de para n-hexano, metanol e etanol diluídos nos óleos vegetais foram determinadas pela técnica do Dilutor na faixa de temperatura entre 313,15 K e 353,15 K. Os dados experimentais obtidos foram comparados com os resultados gerados pelos métodos UNIFAC original e modificado (Dortmund) e para este último modelo, foi proposta uma extensão para os triacilgliceróis. Os dados de foram medidos para 11 misturas contendo solventes e os óleos vegetais relacionados anteriormente na faixa de temperatura de 298,15 K a 383,15 K. Todos os sistemas investigados apresentaram desvio em relação ao comportamento ideal e os valores de apresentaram-se, na maioria, positivos. Dados isotérmicos de ELV foram medidos para misturas entre os mesmos óleos vegetais e metanol, etanol e n-hexano a 348,15 K e 373,15 K através de um método estático. Para misturas com n-hexano, foi observado desvio negativo da lei de Raoult e um comportamento homogêneo, enquanto que as misturas com álcool apresentaram desvio positivo da idealidade e imiscibilidade. Os dados experimentais de ELV foram representados satisfatoriamente pelo modelo UNIQUAC, enquanto que os modelos UNIFAC modificado (Dortmund) e sua extensão proposta para triacilgliceróis foram capazes de predizer os sistemas apenas de forma qualitativa. Finalmente, dados isobáricos de ELV foram medidos para misturas com etanol + óleo de soja a 101,3 kPa e n-hexano + óleo de algodão a 41,3 kPa utilizando o ebuliômetro de Othmer modificado. Os resultados da correlação UNIQUAC também apresentaram boa concordância com os dados experimentais. Este trabalho resultou em um total de 1829 novos dados que irão expandir o banco de dados disponível para compostos graxos, permitindo uma descrição mais precisa do comportamento real de sistemas contendo tais substâncias Abstract: Thermodynamic properties are useful for the reliable design, optimization and modelling of thermal separation processes as well as for the selection of solvents used in extraction processes. They are also required for the development of new thermodynamic models and for the adjustment of reliable model parameters. In order to improve the thermodynamic properties data bank of fatty compounds, the systematic determination of activity Coefficients at infinite dilution ( ), excess enthalpies ( ) and vapor-liquid equilibria (VLE) data of systems containing fatty acids and vegetable oils was performed. The first part of this work presents data for several organic solutes dissolved in saturated and unsaturated fatty acids measured by gas-liquid chromatography at temperatures from 303.13 K to 368.19 K and the comparison to available literature data. Different trends for polar and non-polar compounds could be identified both in the series of fatty acids and as function of temperature. It appears that both the presence and the number of cis double bonds in the fatty acid alkyl chain have influence on the solvent-solute interactions and hence on the values of . The second part of this work deals with measurements performed on systems with refined vegetable oils. Soybean, sunflower and rapeseed oils were submitted to measures of , , and VLE. The measurements of for n-hexane, methanol and ethanol dissolved in these vegetable oils were determined by gas stripping method (dilutor technique) in the temperature range of 313.15 K to 353.15 K. The experimental data were compared with the results of the group contribution methods original UNIFAC and modified UNIFAC (Dortmund) and an extension of the latter method to triacylglycerols was proposed. The data were measured for eleven mixtures containing solvents (organic and water) and the prior mentioned vegetable oils in the temperature range from 298.15 K to 383.15 K. All systems investigated showed deviation from the ideal behavior and their experimental data are mostly positive. Isothermal VLE data have been measured for methanol, ethanol, and n-hexane with the same vegetable oils at 348.15 K and 373.15 K using a computer-driven static apparatus. For mixtures with n-hexane it was observed a negative deviation from Raoult¿s law and a homogeneous behavior, while mixtures with alcohols had a positive deviation from ideal behavior and, in some cases, with miscibility gap. The experimental VLE data were satisfactorily represented by the UNIQUAC model, while the mod. UNIFAC (Dortmund) method and its proposed extension for triacylglicerols were capable of predicting the experimental data only in a qualitative way. Finally, isobaric VLE data were measured for mixtures of ethanol with refined soybean oil at 101.3 kPa and for n-hexane and cottonseed oil at 41.3 kPa using a modified Othmer-type ebulliometer. The results of the UNIQUAC correlation also showed good agreement with the experimental results. This work resulted in a total of 1829 new data that will expand the available fatty compounds data base, allowing a more accurate description of the real behavior of fatty systems Doutorado Engenharia de Alimentos Doutora em Engenharia de Alimentos

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Angelo, Juliana Francisco de. "Aplicação de projeto experimental ótimo à reação de interesterificação de estearina de palma com óleo de linhaça." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/3/3137/tde-09012008-171932/.

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A rapidez da passagem do estágio da bancada para a produção industrial, a rentabilidade econômica do projeto e o custo de investimento da implantação do projeto proposto são medidas da eficiência no desenvolvimento de processos químicos. Com o projeto de experimentos obtém-se uma redução de custo na etapa da experimentação, pela redução no número de experimentos, além de permitir um projeto de um produto com custo e qualidade otimizados. Neste trabalho, o projeto experimental ótimo é aplicado a dados experimentais da reação de interesterificação química da estearina de palma com óleo de linhaça. A gordura obtida pela reação de interesterificação é uma gordura isenta de gorduras trans e possui características nutricionais interessantes devido ao óleo de linhaça, que é a maior fonte do ácido graxo alfa-linolênico, um ácido graxo da família ômega-3. Os dados experimentais são utilizados para desenvolver modelos matemáticos aos quais é aplicada a otimização. Com isto, são previstos pontos ótimos, que são testados. Novos experimentos são realizados na vizinhança dos pontos ótimos. São aplicados os critérios de projeto experimental ótimo D-ótimo e G-ótimo para propor novas condições para a realização de experimentos. Uma vez obtidos estes pontos eles são adicionados aos modelos iniciais para a obtenção de novos parâmetros e é aplicada uma nova etapa de otimização. Nesta metodologia, a cada etapa são desenvolvidos e otimizados modelos matemáticos a partir dos dados experimentais, feita a verificação do ponto ótimo pela realização de experimentos e se esta não é confirmada, são aplicados os critérios de projeto experimental ótimo para a geração de novos pontos que trazem a melhor informação para ser adicionada aos modelos matemáticos. Este procedimento é repetido até a validação do ótimo. Neste trabalho são feitas duas iterações da metodologia onde pode ser observado a melhora de resultados obtidos a cada iteração. The speed at which a process goes from laboratory to industrial scale, the economic rentability of the final project and the investment cost of the proposed project are measures of the efficiency in the development of chemical processes. With the experimental design a reduction of cost in the stage of the experimentation is obtained, by the reduction in the number of experiments, leading to the project of a product with optimum cost and quality. In this work, the application of optimal experimental design to data of the chemical interesterification reaction of palm stearin with linseed oil is presented. The fat produced by the interesterification reaction is free of trans fatty acid and has intreresting nutricionals characteristics due the linseed oil, which is the most important source of alpha-linolenic fatty acid, a omega-3 family fatty acid. The experimental data are used in order to develop mathematical models to which optimization is applied. New experiments, in the vicinity of the predicted optima, are performed and experimental optimal design, D-optimal and G-optimal, is applied in order to generate new conditions for experiments. Once these points are obtained, they are added to the initial models in order to obtain new parameters to which a new stage of optimization is applied. In this methodology, at each stage, mathematical models are developed and optimized from the experimental data and the optima are verified experimentally, and if they are not confirmed, the criteria of optimal experimental design is applied for the generation of new points that bring the best information to be added to the mathematical models. This procedure is repeated until the validation of the optimum. In this work two iterations of the methodology are implemented and the improvement of the results can be observed at each iteration.

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Мінаєва, Ю. А., та Л. П. Сидорова. "Ідентифікація рослинних жирів в маслах та спредах". Thesis, Сумський державний університет, 2017. http://essuir.sumdu.edu.ua/handle/123456789/66515.

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В наш час на ринку України присутня велика кількість фальсифікованої продукції. Найчастіше фальсифікують молочні продукти, а саме вершкове масло. Мета роботи – встановлення фальсифікації молочної продукції жирами рослинного походження шляхом визначення вмісту немолочних жирів.

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Rios, Raquel Vallerio. "Efeitos da substituição de gordura vegetal hidrogenada nas propriedades estruturais de bolos." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/9/9133/tde-14112014-170012/.

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Muitas famílias não têm tempo de preparar bolos caseiros e acabam optando pela praticidade de comprar produtos prontos. A atitude dos consumidores, em relação aos problemas de saúde que podem advir do consumo de alimentos com alto teor de gorduras, é de consumir alimentos formulados de maneira que apresentem menores teores, mas com as mesmas características sensoriais dos produtos originais. O objetivo deste estudo foi determinar o efeito da substituição de gordura vegetal hidrogenada por outros lipídeos (gordura de palma, óleo de soja, óleo de castanha do Brasil, óleo de coco) e por extrato de aveia em formulações de bolos. Foram elaboradas nove formulações contendo farinha de trigo, açúcar, ovo em pó, gordura, água, leite em pó integral, emulsificante, fermento químico e sal, substituindo-se a gordura vegetal hidrogenada pelos diferentes tipos de lipídeos e extrato de aveia. Formulações: (controle) gordura vegetal hidrogenada (GVH) - 100%; (1): gordura de palma - 100%; (2): óleo de soja - 100%; (3): óleo de castanha do Brasil - 100%; (4): óleo de coco - 100%; (5): extrato de aveia - 100%; (6): GVH - 50% + óleo de castanha do Brasil - 50%; (7): GVH - 50% + óleo de coco - 50%; (8): GVH - 50% + extrato de aveia - 50%. Através das análises de textura com probes back extrusion e de compressão (TPA-análise do perfil de textura) pode-se avaliar, respectivamente, o comportamento das massas de bolos e o shelf-life dos produtos finais durante seis dias de armazenamento. Foram feitas avaliações de volume específico, densidade, porosidade, composição centesimal e atividade de água - aw. A análise sensorial com 60 provadores foi realizada utilizando-se as formulações controle, óleo de coco, óleo de castanha do Brasil e extrato de aveia de acordo com a escala hedônica (9 pontos) e intenção de compra. A análise de textura (back extrusion) apontou diferentes comportamentos reológicos, embora todas as formulações caracterizaram-se como fluido dilatante (n>1). O resultado do shelf-life mostrou que o bolo produzido com extrato de aveia obteve melhores características de qualidade. O bolo produzido com GVH apresentou maior volume (2,65 mL/g), menor densidade (0,39 g/mL)e maior incorporação de ar (16,45 mm2). A análise de cor apontou que o bolo elaborado com GVH + óleo de coco apresentou-se mais amarelado (35,94) e o bolo com GVH + extrato de aveia com maior brilho (75,27). A composição centesimal mostrou as variações obtidas de acordo com a substituição de gordura por extrato de aveia e o menor valor calórico (257,62 kcal) para este produto. O resultado de aw mostrou maior valor para a formulação com extrato de aveia (0,94), sendo esperado devido ao maior conteúdo de água da formulação. A análise sensorial, através da avaliação de painel não treinado, indicou que o bolo elaborado com óleo de coco obteve a maior aceitação e, consequentemente, a maior intenção de compra, entretanto, apresentou pouca diferença em relação ao bolo controle. Em geral, os resultados mostraram ótimo padrão de qualidade dos bolos elaborados com a substituição da gordura vegetal hidrogenada, podendo-se assim, obter produtos com outras opções de ingredientes e com agregação de valor nutricional. Many families do not have time to prepare homemade cakes and usually opt for the convenience of buying ready products. Consumer\'s attitudes regarding health issues, that may arise from the consumption of foods high in fat, is to consume foods that have formulated so low in fat, but with the same sensory characteristics of the original products. The purpose of this study was to determine the effect of replacing hydrogenated vegetable fat for other lipids (fat palm, soybean oil, Brazil nut oil, coconut oil) and oat extract in cake formulations. Nine formulations containing flour, sugar, egg powder, fat, water, whole milk powder, emulsifier, baking powder, and salt were elaborated by replacing the hydrogenated vegetable fat for different types of lipids and oat extract. Formulations: (control) hydrogenated vegetable fat (GVH) - 100%; (1): palm fat - 100%; (2) soybean oil - 100%; (3): Brazil nut oil - 100%; (4) coconut oil - 100%; (5): oat extract - 100%; (6): GVH - 50% + nut oil from Brazil - 50%; (7) GVH - 50% Coconut oil + - 50%; (8): GVH - 50% + oat extract - 50%. The behavior of cakes batters and shelf life of the final product during six days of storage were assessed through the texture analysis with probes back extrusion and compression (TPA-texture profile analysis), respectively. The evaluation of specific volume, density, porosity, chemical composition and water activity - aw was made. Sensory analysis was performed with 60 tasters using the control formulations, coconut oil, Brazil nut oil l and oat extract according to the hedonic scale (9 points) and purchase intent. Texture analysis (back extrusion) showed different rheological behaviors, although all formulations were characterized as a dilatant fluid (n> 1). The result of the shelf-life showed that the cake made with oat extract produced better quality characteristics. The cake produced with GVH showed higher volume (2,65 mL/g), lower density (0,39 g/mL) and greater incorporation of air (16,45 mm2). The color analysis showed that the cake made with coconut oil + GVH presented more yellowness (35,94) and cake with GVH + oat extract presented higher brightness (75,27). The chemical composition showed variations obtained in accordance with the substitution of fat for oat extract and lower caloric value (257,62 kcal) for this product. The result showed higher aw value (0,94) for the formulation with oat extract, it is expected due to the higher water content of the formulation. The sensory analysis, through evaluating untrained panel, indicated that the cake prepared with coconut oil had the highest acceptance and, consequently, the higher purchase intention, although it presented little difference from the control cake. In general, the results showed great standard of quality cakes prepared by replacing the hydrogenated vegetable fat, leading to products with other options of ingredients and with added nutritional value.

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Muniz, Adriana. "Efeito da adição do óleo de soja, óleo de linhaça, óleo de coco babaçu e sebo bovino nos parâmetros produtivos e reprodutivos de fêmeas suínas em lactação." Universidade de São Paulo, 2004. http://www.teses.usp.br/teses/disponiveis/10/10131/tde-28082007-095434/.

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O objetivo do experimento foi verificar o efeito da adição do óleo de soja, óleo de linhaça, óleo de coco babaçu e sebo bovino na ração de fêmeas suínas lactantes. As dietas eram energeticamente altas, sendo uma dieta basal acrescida em 8% por diferentes fontes de energia, (1) óleo de soja, (2) óleo de linhaça, (3) óleo de coco e (4) gordura animal, tratamentos 1, 2, 3 e 4 respectivamente. O experimento foi realizado na Fazenda Santa Rosa, Leme, SP. As variáveis avaliadas foram peso inicial, aos 100 dias de gestação (PI), peso à desmama (PD), espessura de toucinho aos 100 dias de gestação (ETI), espessura de toucinho à desmama (ETD), mudanças corporais no período lactacional como perda de peso (PP), perda de espessura de toucinho (PET), produção de leite (PL) e peso dos leitões (Ple) nos dias 7, 14 e 21 da lactação, intervalo desmama estro (IDE), duração do estro (DE) e concentrações de estrógeno (Es) à desmama, 48 horas após a desmama e no estro. A espessura de toucinho foi medida no P2. A técnica de PL foi realizada pela técnica de peso dos leitões antes e depois das mamadas. O manejo para diagnóstico do estro foi realizado duas vezes ao dia. As coletas de sangue foram realizadas em 3 ocasiões à desmama (Dia 1), 48 horas após a desmama (Dia 2) e na comprovação do estro (Dia 3). As análises da (Es) foram realizadas pela técnica de radioimunoensaio. Foram utilizadas 24 fêmeas, em um delineamento inteiramente ao acaso. Os resultados foram analisados através do programa computacional Statistical Analysis System (SAS Institute Inc., 1985) submetidos à análise de variância pelo procedimento GLM (PROC GLM). Para os valores de peso, espessura de toucinho, bem como das mudanças no período não houve diferença significativa, e os resultados foram para PI 257,7; 259,3; 265,0 e 267,0 quilos e para PD 231,3; 217,4; 224,9 e 225,0 quilos para os tratamentos 1, 2, 3 e 4, respectivamente. Os valores de 17,0; 16,5; 16,5; 16,0 milímetros foram para ETI e 13,2; 12,13; 12,5 e 12,0 mm para ETD nos tratamentos 1, 2, 3 e 4, respectivamente. A PP durante a lactação foi de 44,4; 41,9; 40,1 e 39,1 para os tratamentos 1, 2, 3 e 4, respectivamente. Já a PET apresentou médias de 3,8; 4,2; 4,0 e 4,0 mm nos tratamentos 1, 2, 3 e 4, respectivamente. Não foi encontrada diferença significativa para PL, bem como para os diferentes dias de mensurações tendo como resultados no 7º dia 10,13; 9,43; 8,98 e 8,85 Kg para os diferentes tratamentos 1, 2, 3 e 4, respectivamente. No 14º dia os valores médios para os tratamentos foram de 10,12; 11,20; 10,26 e 8,79 Kg, respectivamente, e os valores de 11,34; 10,47; 10,56 e 10,76 Kg para os tratamentos 1, 2, 3 e 4, respectivamente para o 21º dia. O peso dos leitões não foi significativo entre os tratamentos, mas apresentou significância nos três diferentes tempos (P < 0,01) e os valores médios foram de 2,87; 2,95; 2,83 e 2,9 Kg para os tratamentos 1, 2, 3 e 4, respectivamente para o 7º dia de amamentação, de 5,01; 4,88; 4,8 e 4,75 Kg nos tratamentos 1, 2, 3 e 4, respectivamente para 14º dia. Já para o 21º dia os valores nos tratamentos 1, 2, 3 e 4, respectivamente foram de 6,80; 6,58; 6,56 e 6,82 Kg. O IDE e DE não apresentaram diferença significativa e tiveram como médias nos respectivos tratamentos 1, 2, 3 e 4 de 74,0; 68,0; 70,3 e 78,7 horas para IDE e 57,6; 62,0; 64,0 e 72,0 para DE. Para as médias de Es não houve significância e estas apresentaram os seguintes valores de 10,25; 12,82; 9,65 e 8,71 pg/ml nos respectivos tratamentos 1, 2, 3 e 4 no dia 1. Para o dia 2 os valores nos tratamentos 1, 2, 3 e 4 foram de 25,8; 27,39; 24,64 e 32,12 pg/ml respectivamente, e os valores de 83,6; 79,14 e 77,64 pg/ml para os tratamentos 1, 2, 3 e 4, respectivamente referentes ao dia 3. Twenty-four Dalland C40 sows were used in one experiment to study the effect of dietary vegetable oil or tallow on productive and reproductive parameters. All sows were fed a corn-soybean meal diet supplemented with 8% soybean (T1), linseed (T2), coconut (T3) oil or tallow (T4) from day 100 of gestation and throughout the lactation period. Sow initial weight and backfat thickness were determined at day 100 of gestation (ISW and IBT, respectively), and at weaning (WSW and WBT, respectively). Sow weight and backfat thickness losses (WL and BTL, respectively) were calculated, and milk yield (MY) was estimated at day 7, 14 and 21 of lactation by weighing the litter before and after suckling. Interval weaning estrus (IWE), and estrus duration (ED), and piglet weight (PW) were recorded. Blood samples were taken at weaning (day 1), and 48 hours after weaning (day 2), and at onset of estrus (day 3) for estradiol (E2) determination. There were no treatment effects for the parameters studied. The means for E2 were 10.25; 12.82; 9.65 e 8.71 pg/ml (day 1), and 25.8; 27.39; 24.64 e 32.12 pg/ml (day 2), and 83.6; 79.14 e 7764 pg/ml (day 3) for treatment 1, 2, 3 e 4, respectively. Means for E2 on day 3 were higher than values observed on day 1 and 2.

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Castellote, Bargalló Ana Isabel. "Analítica de triglicéridos por cromatografía líquida de alta eficacia: aplicaciones a aceites de origen vegetal." Doctoral thesis, Universitat de Barcelona, 1987. http://hdl.handle.net/10803/672886.

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Dado el gran interés que despierta dentro del campo del análisis de lípidos la determinación de la composición triglicérica y por lo tanto el disponer de un método aplicable al análisis rutinario, se han puesto a punto dos técnicas por cromatografía liquida de alta eficacia (CLAE) para el análisis de triglicéridos que utilizan dos sistemas de detección distintos: detector de índice de refracción (IR) y detector UV a longitudes de onda bajas. Una vez optimizados los parámetros cromatográficos y estudiado los aspectos cuantitativos de ambas técnicas (linealidad de respuesta, límites de detección cuali y cuantitativos, factores de respuesta, repetibilidad y reproductibilidad) se comparan ambas, eligiéndose la CLAE-IR como la mas óptima. Esta técnica se aplica primero al estudio cualitativo de los triglicéridos de los aceites de oliva, soja, girasol, maíz, coco y palma, caracterizándolos por sus perfiles cromatográficos. Seguidamente, sobre un total de 138 muestras, se aplica la técnica al estudio cuantitativo de los triglicéridos del aceite de oliva, tanto para su caracterización (estableciendo los valores medios de los triglicéridos en los aceites vírgenes) como para la diferenciación entre los cuatro tipos que contempla el C.A.E.: aceites vírgenes, puros, refinados y de orujo de aceituna. Asimismo se establecen subgrupos dentro de los aceites vírgenes según su procedencia: Andalucía, País Valenciano y Cataluña, y dentro de esta última, también según sus dos denominaciones de origen (D.O. Borges Blanques y D.O. Ciurana) para proceder también a su posterior diferenciación. Finalmente se hace un estudio de las posibilidades de la aplicación de la técnica de cromatografía liquida de alta eficacia con detector de IR a la detección de fraudes de aceites de oliva con aceites de semillas a través de las variaciones de su composición triglicérica.

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Oliveira, Tiago Marcelo. "Desempenho atlético e adaptação metabólica de cavalos Árabes em testes de longa duração em esteira suplementados com óleo de arroz ou óleo de soja." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/10/10136/tde-08102012-153800/.

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Suplementação com óleos vegetais tem sido usada frequentemente na dieta de equinos atletas. O objetivo desse trabalho é avaliar e quantificar o metabolismo lipídico em testes de longa duração e o desempenho atlético em testes de esforço máximo em equinos suplementados com diferentes óleos vegetais. Doze equinos da raça Árabe, não treinados, foram divididos em dois grupos, sendo que cada grupo foi suplementado com 200ml de óleo de soja ou arroz (9% do concentrado) por um período de seis semanas. Antes e após esse período, esses animais foram submetidos um teste de esforço máximo (TPEP) e um teste de longa duração (TLD) em esteira, quando foram coletadas amostras de sangue antes, durante e após o exercício. A velocidade no TLD foi determinada pelo índice V150 individual, obtido no TPEP de cada animal. Os animais apresentaram boa aceitabilidade e adaptação à dieta. No TPEP os valores de lactato plasmático nos animais após suplementação foram menores durante e maiores após o exercício (p<0,05). No grupo soja, houve em média uma diminuição nos níveis de glicose no plasma, enquanto que no grupo arroz, observou-se aumento desses níveis (p<0,01). No TLD houve aumento nos valores séricos de ácidos graxos livres (AGL) e colesterol, e redução nos valores de triglicérides nos animais após suplementação nos dois grupos (p<0,05). No grupo suplementado com óleo de arroz houve diminuição nos valores de LDL (p<0,05). Em ambos os grupos não houve alterações significativas nos valores de HDL, Aspartato Aminotransferase (AST), Creatina quinase (CK), Fosfatase Alcalina (FA), glicose e lactato no TLD após a suplementação. O V150 foi eficaz para determinar uma predominância do metabolismo aeróbico, no qual a gordura é mais utilizada como substrato para produção de energia. Nos animais após suplementação com óleo houve um atraso no limiar de lactato no TPEP e aumento da disponibilidade de energia no exercício de longa duração através do aumento de AGL e manutenção dos níveis de lactato. As alterações no metabolismo lipídico causadas pela suplementação com óleo podem favorecer o desempenho desses animais tanto em testes de esforço máximo como em testes de longa duração. Vegetable oil supplementation has been often used in high performance horses feeding. The aim of the current study is to evaluate and to quantify the lipidic metabolism during the low intensity tests and exercise performance during incremental exercise tests in fat-supplemented horses. Twelve Arabian horses, untrained, were divided into two groups, which each group was supplemented with 200 ml of soybean oil or rice bran oil (9% of the concentrate) for a period of six weeks. Before and after this period, they were submitted to incremental exercise test (IET) and low intensity test (LIT) on a high-speed treadmill, and blood samples was taken before, during and after exercise. The velocity in the LIT was determined by individual V150 in IET. Good acceptability and adaptation to diet was observed. In IET the plasma lactate values in fat-supplemented horses was lower during the exercise and higher after exercise (p<0,05). In the soybean group, there was decrease in plasma glucose levels, while in the rice bran group, there was increase in plasma glucose levels (p<0,01). In LIT there was increase in serum free fat acids (FFA) and cholesterol levels, and decrease in serum triacylglycerol levels in fat-supplemented horses in both groups (p<0,05). In the rice bran group there was decrease in serum LDL values (p<0,05). No significant difference was observed in HDL, Aspartate Aminotransferase (AST), Creatine Kinase (CK), Alkaline Phosphatase (AP), glucose and lactate values in LIT after supplementation. V150 was a good index to determinate a prevalent aerobic metabolism, which fat was better used as energy source. There was a delay in the lactate threshold and increase of energy availability during low intensity exercise by increasing of FFA and the maintenance of the lactate levels in fat-supplemented horses. Changes in the lipidic metabolism provided by oil supplementation can favor the performance during IET and LIT.

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Rocha, Mayara Ribeiro. "Avaliação das propriedades sensoriais dos produtos de interesterificação da gordura do leite com óleos vegetais." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/97/97137/tde-20112017-123439/.

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A procura dos consumidores por produtos mais saudáveis, combinada às descobertas científicas sobre os efeitos na saúde humana de diversos alimentos, gerou a busca por processos adequados à produção de alimentos. Neste contexto, óleos e gorduras modificados têm ganhado atenção especial. Uma opção industrial para modificar as propriedades dos óleos e gordura é por meio de reações de interesterificação catalisadas por agentes químicos ou bioquímicos. O presente trabalho teve como objetivo, verificar a influência do tipo de catalisador (metóxido de sódio e lipase de Rhizopus oryzae imobilizada em silica-PVA) nas propriedades sensoriais dos produtos obtidos por interesterificação da gordura do leite anidra e dois óleos vegetais (soja e canola). A avaliação sensorial feita através de um nariz eletrônico e um texturômetro, utilizando matérias-primas que estavam de acordo com as normas brasileiras e adequadas para as duas rotas de interesterificação. As reações de interesterificação química foram realizadas em rotaevaporador de baixa pressão contendo 320g da mistura (65% de gordura do leite e 35% de óleo vegetal) e 0,75% de metóxido de sódio a 60°C por 60min. As reações de interesterificação enzimática foram realizadas em reatores cilíndricos encamisados, carregados com 70g de meio (65% de gordura do leite e 35% de óleo vegetal) incubadas com derivado imobilizado na proporção fixa de 500 unidades de atividade por grama de meio (500U/g). As reações foram conduzidas por 6 horas, com agitação magnética, em atmosfera inerte (N2), ao abrigo da luz, a 45°C. Os resultados mostraram que os sensores do nariz eletrônico discriminaram as amostras satisfatoriamente e que o tipo de catalisador influenciou de forma marcante no aroma dos produtos interesterificados, independentemente do tipo de óleo usado. Este fato pode ser atribuído à especificidade do catalisador enzimático (enzima 1,3 específica) que atua nos carbonos 1,3 do glicerol enquanto na interesterificação química a distribuição dos triacilgliceróis ocorre ao acaso, imprimindo no painel dos componentes principais do aroma posições opostas. Especificamente, verificou-se que os aromas dos produtos interesterificados pela rota enzimática ficaram localizados em posição mais próxima à dos óleos vegetais, enquanto pela rota química os produtos obtidos ficaram mais próximos aos componentes dos aromas da gordura de leite e das misturas gordura e óleos vegetais. Apesar desta metodologia não permitir identificar que tipo de aroma poderia ser mais agradável ao consumidor, é possível afirmar que o catalisador tem uma influência importante no aroma de produtos obtidos por interesterificação. Com relação à textura, ambas as rotas geraram produtos com consistências adequadas ao critério estabelecido por Haigton. Consumers\' demand for healthier products, combined with scientific discoveries about the effects of different foods on human health, has generated the search for suitable processes for the production of food. In this context, oils and modified fats have gained special attention. Reactions catalysed by chemical or biochemical agents are an industrial option to modify the properties of the oils and fat by means of its interesterification. This study aimed to verify the influence of the type of catalyst (sodium methylate and Rhizopus oryzae imobilizada on silica PVA) on the sensory properties of the products obtained by interesterification anhydrous fat milk and two vegetable oils (soybean and canola). Sensory evaluation was made through an electronic nose and texturometer, using raw materials that were in accordance with Brazilian rules and appropriate standards for the two routes of interesterification. The chemical interesterification reactions were performed at low pressure rotaevaporator, the mixture containing 320g (65% milk fat and 35% vegetable oil) and 0.75% sodium methoxide at 60° C for 60min. The enzymatic interesterification reactions were carried out in cylindrical jacketed reactors loaded with 70g of médium (65% milk fat and 35% vegetable oil) incubated with immobilized derivative in a fixed proportion of 500 activity units per gram of reaction medium (500U / g). The reactions were conducted for 6 hours, with magnetic stirring under inert atmosphere (N2), protected from light, at 45 ° C. The results showed that the sensors of the electronic nose discriminated samples satisfactorily and that the type of catalyst influenced markedly in the aroma of interesterified products regardless of the type of oil used. This fact can be attributed to the specificity of the enzyme catalyst (1.3-specific enzyme) that acts on the 1,3 carbons of the glycerol as chemical interesterification of triacylglycerols distribution occurs randomly, printing on the panel of the components of the aroma opposite positions. Specifically, it was found that the scent of interesterified product by enzymatic route were located in the nearest position to the vegetable oil, while by the chemical route the products obtained were closest to the components of milk fat flavors and mixtures fat and vegetable oils . Although this methodology cannot identify what kind of aroma could be more pleasant to the consumer, it is clear that the catalyst has an important influence on product aroma obtained by interesterification. Regarding the texture, both routes generated products with suitable consistency to the criteria established by Haigton.

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Ramos, Boris. "Production of biodiesel from vegetable oils." Thesis, KTH, Skolan för kemivetenskap (CHE), 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-145863.

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The production of biodiesel using vegetables oils is studied. Palm oil and its use for production of biodiesel have been focused. Palm tree is very productive and one of the most profitable for biodiesel production. Among the oilseed crops palm tree produce more oil per hectare. Palm oil has a good availability and a competitive price. The production of palm oil at the industrial plantation level has caused environmental damage. The Roundtable on Sustainable Palm Oil has established principles and criteria in order to certify a sustainable cultivation of the palm oil. The experimental work involves the production of biodiesel using corn oil. Ethanol and methanol are used as alcohols. Sodium and potassium hydroxides are selected as catalyst. The ratio alcohol to oil is the most important parameter in the production of biodiesel. An excess of alcohol is required to drive the reaction to the right. In the experiments with ethanol the yield of biodiesel increased with the ratio ethanol/oil achieving the highest yield at a molar ratio ethanol/oil: 7.78. In the experiments with methanol, using 0.9 g NaOH and 1 hour reaction time the highest yield was obtained with a molar ratio methanol:oil = 9. Using KOH as catalyst and 2 hour reaction time a very good yield is already obtained with a molar ratio methanol:oil = 4.5 The amount of catalyst is another studied parameter. In the experiments with ethanol, the amount of 0.8 mg NaOH and 1.2 mg KOH for 200 ml corn oil (0.22 mol) is enough in order to obtain a good yield. An increase of the amount of catalyst does not produce an increase of the yield of biodiesel. In experiments with methanol, using the lowest tested amount catalyst (0.85 g KOH and 0.23 g NaOH) a good yield of biodiesel is obtained. The effects of the reaction time, rate of mixing and the reaction temperature were studied in the experiments with methanol. The yield of biodiesel increased when the reaction time is increased from 1 to 2 hours. The yield of produced biodiesel increased from 90% to 94% when the rate of mixing was increased from 500 to 1500 rpm. Often the transesterification is carried out at a temperature near the boiling point of alcohol. The highest yield was obtained at 60 oC with KOH and at 55 oC using NaOH but already at 40 oC a good yield was obtained (89%).

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Sacchetti, Annalisa <1994&gt. "Catalytic hydrogenation of vegetable oils derivatives." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2022. http://amsdottorato.unibo.it/10070/1/Sacchetti%20Annalisa_final%20upload%20.pdf.

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During this project the catalytic hydrogenation of a mixture of fatty acids derivatives was performed in two different reactors (discontinuous batch and continuous flow); the attention was pointed out on the type of the catalyst employed, involving a screening among different noble metals and support with optimization of the reaction parameters. Interesting results were obtained in batch reactions with 0.3% wt Pd/C at 4 bar of H2 and 90°C, ensuring full conversion of the starting material and complete selectivity towards the saturated compounds. An insight of the kinetics of the reaction was performed, conducting the reaction for different time (0-6 hours). Also, fundamental parameters such as H2 pressure, stirring rate, temperature, metal type and support were evaluated for determining the most advantageous conditions to guarantee complete starting material conversion and high yields of desired products. The same tests were then performed employing a continuous flow reactor, confirming the high activity of 0.3% wt Pd/C at low contact time of 0.2 min. Despite stunning results were achieved with a single batch (discontinuous) or for low reaction time (1h in continuous), the catalyst performance started to worsen for multiple batch or longer time respectively. Investigations on the cause were executed, excluding immediately metal leaching thanks to ICP-AES analysis. Deactivation was attributable to absorption of reactants on the catalyst surface, which could lead to formation of oligomers. It was found that the deactivation rate, in the continuous reactor, was directly dependent on the hydrogen pressure, the contact time but even more importantly to the composition of the starting material: an increase of poly-unsaturated fatty acids derivatives affected negatively the catalyst stability, causing a faster decline of conversion and higher decrease in selectively. This was associated to a strong adsorption with consequent formation of oligomers, which occupied the active site, worsening the catalyst’s performance.

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Brekke, Sarah. "Trans-free fats and oils: chemistry and consumer acceptance." Kansas State University, 2013. http://hdl.handle.net/2097/16268.

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Master of Science Department of Food Science Delores Chambers Research has shown that trans fat consumption increases the levels of low-density lipoprotein (LDL) and has a direct correlation to the incidence of heart disease. It is now widely believed that trans fat intake adversely affects the health of consumers. A Food and Drug Administration (FDA) ruling, effective January 1, 2006, required declaration of trans fat content on all Nutrition Facts labels of food products. Around the same time local governments, such as the city of New York, and some restaurants followed suit by eliminating trans fats from their menus. The food industry’s initial concern with trans fat elimination/reduction was the loss of some functionality such as shelf life, stability, and creaming ability with trans-free fats and oils. Researchers are working to develop new trans-free fats and oils that do not have negative sensory properties and maintain the functionality of traditionally hydrogenated oils when used in baked and fried goods. This is an overview of the chemistry, health risks, and research that has been performed to either reduce or eliminate trans fats in food products.

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Lamb, Kelsey Ellen. "THE SURVIVAL OF VARIOUS PATHOGENIC ORGANISMS IN FATS AND OILS." UKnowledge, 2017. http://uknowledge.uky.edu/animalsci_etds/72.

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The research within this thesis sought to determine the ability of various animal derived fats and plant derived oils to support the survival of several pathogenic cocktails over a multitude of storage times. The Salmonella study explored the survival rate of a four strain Salmonella cocktail in beef tallow, pig lard, duck fat, coconut oil, and extra virgin olive oil over seven days at 26˚C and 37˚C storage. The animal fats and the coconut oil supported the survival of the bacteria until the conclusion of the study. The Shiga-toxin producing Escherichia coli study explored the survival rate of a five strain STECs cocktail in extra virgin olive oil over seven days at 26˚C and 37˚C storage. The two Listeria studies explored the survival rate of a four strain Listeria monocytogenes cocktail in extra virgin olive oil over several time periods with different frequencies of sample mixing. In vitro, all genuses showed a 2.5-log cfu/mL to ≥ 7-log cfu/mL reduction in the extra virgin olive oil by the conclusion of the experiments. Extra virgin olive oil was then applied to cooked pork tenderloin, cheddar cheese snack squares, and turkey lunchmeat in hopes of inhibiting the L. monocytogenes cocktail. No reduction was observed.

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Lazarick, Kelsey. "Cause of color component formation in oils during frying." Thesis, Lethbridge, Alta. : University of Lethbridge, Dept. of Chemistry and Biochemistry, c2012, 2012. http://hdl.handle.net/10133/3303.

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Color formation in oils during frying is one of the most noticeable degradation reactions that occur in the frying oil. Degradation reactions cause formation of products that positively and negatively impact the nutritional and sensory qualities of both the food being fried and the frying oil. The origins of these pigment forming reactions in the oil and the factors affecting these reactions are not well understood. Assessments of the mechanisms, the components involved and external conditions affecting oil darkening were conducted. The effect of basic food ingredients, commercially sold and laboratory formulated breading and battering, preformed lipid hydroperoxides and phospholipids on color formation and oil degradation of the frying oil were investigated. Protein products, specifically whey protein, caused both the fastest darkening and thermo-oxidative deterioration of the frying oil. This breakdown was aided further through the addition of minor food materials such as glucose and amino acids as well as lipid hydroperoxides in concentrations greater than 5 % of the frying oil. Nonenzymatic browning is the main reaction causing color formation in the frying oil and utilizes carbonyls from the food product such as starches, sugars and lipid oxidation products as starting materials alongside amino groups from proteins and amino acids. Breading ingredients contributed to oil color formation due to particles from the food crust breaking off into the frying oil to further accelerate browning reactions. Increasing the temperature of the frying oil provided additional stimulus for color forming and thermo-oxidative reactions to progress at a faster rate. xv, 184 leaves : ill. ; 29 cm

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Aladedunye, Adekunle Felix. "Inhibiting thermo-oxidative degradation of oils during frying." Thesis, Lethbridge, Alta. : University of Lethbridge, Dept. of Chemistry and Biochemistry, 2011, 2011. http://hdl.handle.net/10133/3257.

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The present study sought for practical ways to improve the frying performance of oils without compromising the availability of the essential fatty acids and nutraceuticals. To this end, the influence of temperature, oxygen concentrations, and compositions of minor components on frying performance was investigated. A novel frying protocol, utilizing carbon dioxide blanketing, was developed and found to significantly improve the performance of the frying oil. Optimizing both the amounts and the compositions of endogenous minor components also improved the performance of the frying oil. Twenty one novel antioxidants were synthesized and evaluated under frying and storage conditions. Antioxidant formulations consisting of a combination of endogenous and synthesized antioxidants were developed and tested in an institutional frying operation. A rapid and effective frying test was developed to assess the frying performance of oils and applied antioxidants. Furthermore, a novel procedure for direct hydroxynonenal analysis in frying oil was developed. xx, 249 leaves; 29 cm

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Cancelliero, Ana Carolina. "Detecção da origem das matérias graxas presentes em requeijões e similares encontrados no mercado." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/11/11141/tde-22112007-103737/.

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O objetivo desse estudo foi validar a aplicação da metodologia isotópica de identificação da origem dos gliceróis em gorduras presentes em requeijões e especialidades lácteas com o intuito de oferecer uma ferramenta de controle de qualidade, de fiscalização de mercado e detecção de fraudes. Para atingir esse objetivo, isolou-se o glicerol de compostos lácteos como requeijões, especialidades lácteas, leite e óleos vegetais (empregados como padrões de origem animal e vegetal, respectivamente) e aplicou-se a metodologia isotópica. O glicerol foi isolado através da centrifugação. Foram analisadas todas as marcas de requeijões e similares (28 marcas) disponíveis nos supermercados da cidade de Piracicaba, e depois, agrupadas conforme sua identificação: requeijão cremoso, especialidade láctea com requeijão cremoso, alimento à base de requeijão e creme vegetal, requeijão cremoso com amido e não identificado. Do total, cinco marcas apresentaram resultados com diferença significativa (p<0,05) quando comparados ao controle (padrão animal leite). A metodologia isotópica permitiu identificar a origem do material analisado e detectar alterações nos padrões. Comprovou-se a eficácia da metodologia isotópica na identificação da origem da matéria graxa de requeijões e a aplicabilidade da técnica no controle de qualidade de lácteos, auxiliando tanto no recebimento de matéria-prima como de produto final. The objective of this study was to validate the application of the isotopic methodology of identification of glycerol origin in the fat fraction of "requeijões" (Brazilian soft cheeses) and similar products aiming at the identification of a quality control instrument for market fiscalization and fraud detection. In order to pursue the specific objectives of this study, the glycerol was isolated from spreadable dairy products such as "requeijões" and others. Cow's milk and vegetable oils of known origins were adopted as standards. The isotopic methodology was applied to identify the origin of the carbon present in the glycerol molecule of the fats present in those foods. Glycerol was isolated according to a conventional based on centrifugation. Twenty-eight commercial brands of "requeijões" available in the supermarkets of Piracicaba city were classified according to the information provided in the lables and analyzed. Out of the total, 5 brands were significantly different (p<0,05) when compared to the control (animal pattern - milk), indicating absence of the milk fat in the formulation. The isotopic methodology allowed to identify the origin of the analyzed material and to detect alterations in the patterns. The effectiveness of the isotopic methodology in the identification of origin of the lipid constituents of "requeijão" was proven as well as the applicability of the technique in dairy industry quality control, both in the final product as well as in process supplies.

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19

Tu, Qingshi. "Fats, Oils and Greases to Biodiesel: Technology Development and Sustainability Assessment." University of Cincinnati / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1448037796.

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20

Jia, Huanfei. "Pretreatment of wastewater containing fats and oils using an immobilized enzyme." Thesis, Curtin University, 2002. http://hdl.handle.net/20.500.11937/448.

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This thesis investigates an application of immobilized lipase for pre-treating wastewater containing fats and oils, which is difficult to treat practically. The kinetics of soluble lipase was studied for establishing background of the lipase. The immobilization of lipase was adopted in order to repeatedly use the expensive lipase. The developed immobilization methods were based on the characteristics of carriers, but covalent bonding of lipase was preferred because of strong adsorption nature. Three types of materials, nylon membrane and polystyrene-divinylbenzene and silica gel beads, were used for studying the lipase immobilization characteristics. The lipase from Canada rugosa was chosen because of its relatively high catalytic activity and commercial availability. The oily wastewater sources used were a simulated mixture of olive oil and distilled water as well as actual restaurant oily wastewater. A packed bed reactor packed with immobilized lipase was suitable for the study. Moreover, a comparative study of anaerobic digestion of lipase treated and un-treated oily wastewater was undertaken to evaluate the efficiency of the lipase pre-treatment method due to lack of the relevant literature in the enzymatic wastewater treatment field. The kinetics of lipase catalyzed hydrolysis reactions was investigated in a stirred tank reactor. The experimental results confirmed that the lipase catalyzed reaction obeyed Michaelis-Menten model. The optimal pH and temperature of the lipase catalysed hydrolysis reaction were 7 and 37°C, respectively. The conversion of oil to fatty acid was dependent on the reaction time and mass of the enzyme used. The lipase activities depended on the concentrations of some selected additives. Calcium ion improved lipase activity significantly amongst the additives used.The immobilization of lipase was carried out using different materials, nylon membranes, polystyrene-divinylbenzene beads, and silica gel. Covalent adsorption was simple and successful for immobilizing the lipase onto nylon membrane which was pre-treated with HC1 solution for releasing amino groups. The adsorption of lipase was completed after only a 2-hour reaction time. It was much more practical for this shorter adsorption time (2 hours) rather than the 24 hours required for physical capillary adsorption of lipase. The properties of the immobilized lipase and the performance of the reactors we compared amongst the soluble and immobilized lipase forms. The immobilization, particularly for covalent bonding, made lipase more resistant to thermal deactivation. It was evident that the optimum temperature was shifted from 37°C for the soluble lipase to 45 and 40°C for immobilized lipase adsorbed onto nylon and polystyrene-divinylbenzene beads, respectively. The immobilized lipase could be used repeatedly with only little activity loss. The repeatedly operational stability made the reuse of the immobilized lipase possible. Comparison was also made between two types of beads, polystyrene-divinylbenzene beads and silica gels. Though polystyrene-divinylbenzene beads showed higher lipase activity and shorter adsorption time when compared to silica gels, the forme beads were not suggested for large scale study because of high cost of the beads. On improvement achieved in this work was that the 24 hours required for silanization of silica gel was reduced to only a few hours using evaporating 3-APTES in acetone instead of refluxing 3-APTES in toluene.It is worthwhile to point out that much higher enzyme activity was obtained using the packed bed reactor as against the membrane reactor when aqueous oil emulsion was fed into the reactors. The lipase activity was 64.2% of soluble lipase activity for the immobilized lipase in the packed reactor but its activity was hardly detectable in the membrane reactor. Moreover, the operation of the packed bed reactor solved the of separating problem that severely hampered the lipase catalytic activity in the membrane reactor in aqueous phase. This result suggests that the packed bed reacts with the immobilized lipase is applicable in treating oily wastewater. The intrinsic parameters, Vmax and Km, were evaluated to study the internal diffusional effects of the porous spherical silica gel on the immobilized lipase. The changes of Vmax and Km for the immobilized lipase from those of the soluble lipase indicated that some alteration in the lipase intrinsic properties was caused by the immobilization of lipase. However, the magnitude of Thiele modulus suggested the immobilized lipase was most likely reaction controlling. In addition, good agreement for Vmax and Km from experiments and numerical model estimations seemed to suggest that the numerical model could be used for estimating Vmax and Km for the immobilized lipase.An application was tried for conducting the hydrolysis of oily restaurant wastewater by soluble and the immobilized lipase. Enzyme activity of both forms was severely inhibited by the oily wastewater. The enzymatic activity was only 20% and 15% for soluble and the immobilized lipase, respectively, when compared to the initial activity value for the hydrolysis of olive oil by soluble lipase. Evaluation of the efficiency for the proposed lipase pre-treatment method was carried out by monitoring the performance of two anaerobic digesters. These two digesters were fed with lipase treated and untreated restaurant wastewater that was neutralised with KOH solution prior to feeding. The oil-floating problem was minimised by this saponification of fatty acids with potassium hydroxide. However, there was no clear sign of an improvement for the treatment efficiency of the anaerobic digesters in terms of COD removal and methane production rate resulted in digesting lipase treated oily wastewater when compared to the one without lipase pre-treatment.

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21

Jia, Huanfei. "Pretreatment of wastewater containing fats and oils using an immobilized enzyme." Curtin University of Technology, Department of Chemical Engineering, 2002. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=13326.

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This thesis investigates an application of immobilized lipase for pre-treating wastewater containing fats and oils, which is difficult to treat practically. The kinetics of soluble lipase was studied for establishing background of the lipase. The immobilization of lipase was adopted in order to repeatedly use the expensive lipase. The developed immobilization methods were based on the characteristics of carriers, but covalent bonding of lipase was preferred because of strong adsorption nature. Three types of materials, nylon membrane and polystyrene-divinylbenzene and silica gel beads, were used for studying the lipase immobilization characteristics. The lipase from Canada rugosa was chosen because of its relatively high catalytic activity and commercial availability. The oily wastewater sources used were a simulated mixture of olive oil and distilled water as well as actual restaurant oily wastewater. A packed bed reactor packed with immobilized lipase was suitable for the study. Moreover, a comparative study of anaerobic digestion of lipase treated and un-treated oily wastewater was undertaken to evaluate the efficiency of the lipase pre-treatment method due to lack of the relevant literature in the enzymatic wastewater treatment field. The kinetics of lipase catalyzed hydrolysis reactions was investigated in a stirred tank reactor. The experimental results confirmed that the lipase catalyzed reaction obeyed Michaelis-Menten model. The optimal pH and temperature of the lipase catalysed hydrolysis reaction were 7 and 37°C, respectively. The conversion of oil to fatty acid was dependent on the reaction time and mass of the enzyme used. The lipase activities depended on the concentrations of some selected additives. Calcium ion improved lipase activity significantly amongst the additives used. The immobilization of lipase was carried out using different materials, nylon membranes, polystyrene-divinylbenzene beads, and silica gel. Covalent adsorption was simple and successful for immobilizing the lipase onto nylon membrane which was pre-treated with HC1 solution for releasing amino groups. The adsorption of lipase was completed after only a 2-hour reaction time. It was much more practical for this shorter adsorption time (2 hours) rather than the 24 hours required for physical capillary adsorption of lipase. The properties of the immobilized lipase and the performance of the reactors we compared amongst the soluble and immobilized lipase forms. The immobilization, particularly for covalent bonding, made lipase more resistant to thermal deactivation. It was evident that the optimum temperature was shifted from 37°C for the soluble lipase to 45 and 40°C for immobilized lipase adsorbed onto nylon and polystyrene-divinylbenzene beads, respectively. The immobilized lipase could be used repeatedly with only little activity loss. The repeatedly operational stability made the reuse of the immobilized lipase possible. Comparison was also made between two types of beads, polystyrene-divinylbenzene beads and silica gels. Though polystyrene-divinylbenzene beads showed higher lipase activity and shorter adsorption time when compared to silica gels, the forme beads were not suggested for large scale study because of high cost of the beads. On improvement achieved in this work was that the 24 hours required for silanization of silica gel was reduced to only a few hours using evaporating 3-APTES in acetone instead of refluxing 3-APTES in toluene. It is worthwhile to point out that much higher enzyme activity was obtained using the packed bed reactor as against the membrane reactor when aqueous oil emulsion was fed into the reactors. The lipase activity was 64.2% of soluble lipase activity for the immobilized lipase in the packed reactor but its activity was hardly detectable in the membrane reactor. Moreover, the operation of the packed bed reactor solved the of separating problem that severely hampered the lipase catalytic activity in the membrane reactor in aqueous phase. This result suggests that the packed bed reacts with the immobilized lipase is applicable in treating oily wastewater. The intrinsic parameters, Vmax and Km, were evaluated to study the internal diffusional effects of the porous spherical silica gel on the immobilized lipase. The changes of Vmax and Km for the immobilized lipase from those of the soluble lipase indicated that some alteration in the lipase intrinsic properties was caused by the immobilization of lipase. However, the magnitude of Thiele modulus suggested the immobilized lipase was most likely reaction controlling. In addition, good agreement for Vmax and Km from experiments and numerical model estimations seemed to suggest that the numerical model could be used for estimating Vmax and Km for the immobilized lipase. An application was tried for conducting the hydrolysis of oily restaurant wastewater by soluble and the immobilized lipase. Enzyme activity of both forms was severely inhibited by the oily wastewater. The enzymatic activity was only 20% and 15% for soluble and the immobilized lipase, respectively, when compared to the initial activity value for the hydrolysis of olive oil by soluble lipase. Evaluation of the efficiency for the proposed lipase pre-treatment method was carried out by monitoring the performance of two anaerobic digesters. These two digesters were fed with lipase treated and untreated restaurant wastewater that was neutralised with KOH solution prior to feeding. The oil-floating problem was minimised by this saponification of fatty acids with potassium hydroxide. However, there was no clear sign of an improvement for the treatment efficiency of the anaerobic digesters in terms of COD removal and methane production rate resulted in digesting lipase treated oily wastewater when compared to the one without lipase pre-treatment.

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22

Salam, Darine. "Fate and Impacts of Vegetable Oil Spills in Aquatic Environments." University of Cincinnati / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1321367790.

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23

Zamani, Younes. "Determination of physical characteristics of food fats." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape10/PQDD_0007/MQ44324.pdf.

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24

Ziniades, Catherine. "The development of an industrial process to produce AC γ-linolenic acid using Choanephora cucurbitarum". Master's thesis, University of Cape Town, 1990. http://hdl.handle.net/11427/22047.

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Bibliography: pages 163-169. The objective of this work was to produce γ-linolenic acid (γLA) using a fungus in submerged fermentation. Selection work was aimed at identifying a fungal strain capable of yielding a high level of γLA in an industrial fermentation. Thirty-nine fungal strains were screened under shake flask conditions. The major criteria used in evaluating these strains were, the yield of γLA per unit volume (g/l) and γLA as a percentage of fatty acids, which is important in the downstream processing of γLA . Other parameters of industrial importance such as strain handling and the fatty acid profile were also considered. Eleven fungi in the order Phycomycetes were identified after initial screening. From these fungi, a strain of Choanephora cucurbitarum was found to give superior γLA yields. c. cucurbitarum produced γLA yields of 331mg/l and 674mg/l in shake flask and laboratory fermenters respectively. This strain had other industrially beneficial qualities such as good sporulation, a good biomass of 22, 5g/l and a relatively high yield of γLA of 2,99g/100g dry matter. Subsequently a Zygorhynchus heterogamus strain was found to give similar yields of γLA to c. cucurbitarum. z. heterogamus also had a high γLA : linoleic acid ratio which aids the purification of γLA . This is the first known report of a high level of γLA in the genus Zygorhynchus. The industrial development of γLA production by Zygorhynchus is not reported.

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25

Lligadas, Puig Gerard. "Biobased thermosets from vegetable oils. Synthesis, characterization and properties." Doctoral thesis, Universitat Rovira i Virgili, 2006. http://hdl.handle.net/10803/9007.

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Biobased Thermosets from Vegetable Oils. Synthesis, Characterization, and Properties Gerard Lligadas Puig El desenvolupament sostenible va esdevenir com una de les idees claus del segle 20. S'entén per desenvolupament sostenible aquell tipus de desenvolupament que és capaç de satisfer les necessitats actuals sense comprometre els recursos i possibilitats de les futures generacions. Per assolir un desenvolupament sostenible és necessari promoure un desenvolupament social i econòmic pendent en tot moment del medi ambient. La conservació i la gestió dels residus és especialment important en aquest procés. La creixent demanda de productes derivats del petroli, juntament amb la disminució progressiva de les reserves de petroli són algunes de les moltes raons que han encoratjat la industria química a començar a utilitzar les fonts renovables com a matèria prima. En aquest context, en els darrers anys l'atenció s'ha centrat en la utilització de recursos anualment renovables, com són els recursos agrícoles, en la producció d'una gran varietat de productes industrials. Un dels recursos renovables més interessants per a la indústria química són els olis vegetals degut a la seva elevada disponibilitat i el seu ampli ventall d'aplicacions. Els olis vegetals formen part de la família de compostos químics coneguts com lípids, i estan constituïts majoritàriament per molècules de triglicèrids. Els triglicèrids estan formats per tres molècules d'àcid gras unides a una molècula de glicerol mitjançant enllaços ester. Els àcids grassos que es troben en la majoria d'olis vegetals estan constituïts per cadenes alifàtiques insaturades de entre 14 i 22 àtoms de carboni. La explotació industrial dels recursos naturals està actualment en el punt de mira de la comunitat científica. Concretament, el desenvolupament de materials polimèrics derivats de fonts renovables està rebent un interès creixent degut a la incertesa en el preu i les reserves de petroli. La substitució del petroli per productes derivats de fonts renovables és consistent amb el concepte de desenvolupament sostenible. El propòsit del treball portat a terme en aquesta tesi doctoral va ser desenvolupar nous materials termoestables utilitzant olis vegetals com a productes de partida. En el capítol 1 es discuteix la contribució de la química en el desenvolupament sostenible i es descriuen les possibilitats dels olis vegetals com a productes de partida en la síntesi de materials polimèrics. El capítol 2 descriu la preparació de dos noves famílies de materials híbrids orgànics-inorgànics derivats d'olis vegetals. Es descriu síntesi i caracterització de polímers híbrids derivats d'àcids grassos que contenen dobles enllaços carboni-carboni terminals utilitzant la reacció d'hidrosililació com a reacció d'entrecreuament, i la preparació de polímers derivats d'oli de llinosa epoxidat nanoreforçats amb silsesquioxans polièdrics. En el capítol 3 es descriu la síntesi d'un nou compost fosforat derivat de fonts renovables. Aquest compost s'ha utilitzat com a compost retardant a la flama reactiu en la preparació de resines epoxi derivades de fonts renovables amb propietats de resistència a la flama. La incorporació de fòsfor en resines epoxi d'aquest tipus ha donat lloc a polímers amb bones propietats de resistència a la flama. Finalment, en el capítol 4 es descriu la preparació d'una nova família de polièter poliols derivats d'oleat de metil epoxidat com a font renovable. Aquests poliols s'han utilitzat en la síntesi de poliuretans amb aplicacions específiques: poliuretans que incorporen silici amb propietats de resistència a la flama, i poliuretans segmentats amb aplicacions en biomedicina. Biobased Thermosets from Vegetable Oils. Synthesis, Characterization, and Properties Gerard Lligadas Puig Sustainable development, which became a key idea during the 20th century, may be regarded as the progressive and balanced achievement of sustained economic development, and improved social equity and environmental quality. Sustainable development comprises the three components of society, environment, and economy, and its goals can only be achieved if all three components can be satisfied simultaneously. The conservation and management of resources is especially important to this process. The growing demand for petroleum-based products and the resulting negative impact on the environment, plus the scarcity of non-renewable resources, are some of the many factors that have encouraged the chemical industry to begin using renewable resources as raw materials. This situation has led to considerable attention being focused recently on the use of annually renewable agricultural feedstock to produce a wide range of base chemicals and other industrial products. The renewable raw materials that are most important to the chemical industry are natural oils and fats because of their high availability and versatile applications. Vegetable oils constitute about 80% of the global oil and fat production, with 20% (and declining) being of animal origin. The use of these materials offers an alternative approach that is both sustainable and, with the right application, far more environmentally benign than fossil sources. Vegetable oils and fats form part of a large family of chemical compounds known as lipids. Vegetable oils are predominantly made up of triglyceride molecules, which have the three-armed star structure. Triglycerides comprise of three fatty acids joined at a glycerol junction. Most of the common oils contain fatty acids that vary from 14 to 22 carbons in length, with 0 to 3 double bonds per fatty acid. Research into the industrial exploitation of products derived from renewable resources is currently of immense international importance. In particular, the development of polymer materials from renewable resources is receiving considerable attention since the availability of crude oil will become severely restricted within the foreseeable future. The replacement of crude oil by renewable raw materials is also consistent with the aim of global sustainability. The purpose of the study reported in this thesis was to develop new biobased thermosetting polymers from vegetable oils as renewable resources. To achieve this goal, the experimental work focused on exploiting the reactivity of unsaturated fatty compounds. Chapter 1 discusses the contribution of chemistry to sustainable development, and also presents an overview of recent developments in the chemistry of vegetable oil-based polymers. Chapter 2 describes the preparation of two new types of organic-inorganic hybrid materials from vegetable oils. Hybrids with promising properties for optical applications were prepared by the hydrosilylation of alkenyl-terminated fatty acid derivatives with several hydrosilylating agents, and the first example of the preparation of biobased polyhedral oligomeric silsesquioxanes-nanocomposites from vegetable oil derivatives is reported. Chapter 3 describes the synthesis of a new phosphorus-containing fatty acid derivative. This compound is used as a reactive flame-retardant in the preparation of flame-retardant epoxy resins from terminal epoxy fatty acid derivatives. The incorporation of phosphorous into biobased epoxy resins yields polymers with good flame-retardant properties. Finally, chapter 4 describes the preparation of a new family of epoxidized methyl oleate based polyether polyols. These polyols are used in the synthesis of polyurethanes, some with specific applications: silicon-containing polyurethanes with enhanced flame-retardant properties, and polyurethane networks with potential applications in biomedicine.

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26

Fernandes, Vanda Filipa Silva. "Characterization of biodiesels produced from mixtures of vegetable oils." Master's thesis, Universidade de Aveiro, 2010. http://hdl.handle.net/10773/3141.

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Mestrado em Engenharia Química Nos últimos anos o biodiesel tem recebido uma atenção notável devido à sua capacidade de substituir os combustíveis fósseis. É considerado um amigo do ambiente, devido às suas imensas vantagens. Este biocombustível é obtido a partir de recursos renováveis, portanto é considerado biodegradável, CO2-neutro, nãotóxico e reduz significativamente as emissões gasosas com efeito de estufa. É composto por uma mistura de ésteres mono alquílicos obtidos a partir de óleos vegetais, tais como, o óleo de soja, óleo de jatropha, óleo de colza, óleo de palma, óleo de girassol ou a partir de outras fontes como a gordura animal (sebo, banha), restos de óleo e gorduras de cozinha. O processo mais comum para a sua produção é através de uma reacção de transesterificação, onde o óleo vegetal reage com um álcool de cadeia curta na presença de um catalisador. Devido às suas propriedades muito semelhantes ao diesel, são mutuamente miscíveis e assim podem ser misturados em qualquer proporção em ordem a melhorar as suas qualidades. O conhecimento das suas propriedades termofísicas como a densidade e viscosidade, que são afectadas pela temperatura, são muito importantes para a indústria automóvel. Contudo, o biodiesel apresenta algumas desvantagens como elevada densidade, viscosidade, ponto de turvação e escoamento/fluxação em comparação com diesel fuel. O seu comportamento a baixas temperaturas limita a sua aplicação em climas frios, sendo que este comportamento é influenciado pelas matérias-primas e álcool utilizado no processo de produção. Os biodieseis obtidos a partir de óleos com grande teor de ácidos gordos saturados induzem a um pior desempenho a baixas temperaturas, visto que são compostos sólidos a temperaturas mais baixas. Neste trabalho, misturas binárias e ternárias de biodiesel de soja, colza e palma, e diesel fuel foram preparadas e medidas as suas viscosidades dinâmicas e densidade em função da temperatura. Para prever as densidades e viscosidades a partir dos compostos puros são utilizadas regras de mistura. O comportamento a baixas temperaturas dos três biodieseis foi estudado. Onde a composição da fase líquida e sólida e a fracção de sólidos a temperaturas abaixo do ponto de turvação foram analisadas. Aplicou-se um modelo termodinâmico para descrever estes sistemas multifásicos e outros sistemas idênticos. Duas versões do modelo preditivo UNIQUAC, juntamente com uma abordagem que assume uma completa miscibilidade dos componentes na fase sólida, são avaliados em relação aos dados de equilíbrio de fases experimentais medidos. ABSTRACT: In recent years, biodiesel has received a notable attention due its ability to replace fossil fuels. It is considered an environmental friendly due their vast advantages. This biofuel is obtained from renewable resources, so it is considered biodegradable, CO2- neutral, non-toxic and significantly reduces the greenhouse gas emissions. It is composed by a mixture of mono alkyl esters obtained from vegetable oil, such as, soybean oil, jatropha oil, rapeseed oil, palm oil, sunflower oil or from other sources like animal fat (beef tallow, lard), waste cooking oil and grasses. The most common process for its production is by a transesterification reaction, where the vegetable oil reacts with a short chain alcohol in presence of a catalyst. Due to its properties very similar to diesel fuel, they are mutually miscible and so can be mixed in any proportion in order to improve its qualities. The knowledge of its thermophysical properties like density and viscosity, which are affected by temperature, is very import for automotive industries. However, biodiesel present some disadvantages like higher viscosity, density, cloud and pour point compared with diesel fuel. Its behaviour at low-temperature limiting its application in cold climate and these behaviour is influenced by raw materials and the alcohol used in production process. The biodiesel obtained from oils with a major level in saturated fatty acids esters induce a worse behaviour at low temperatures, since they are solid compounds at lower temperatures. In this work, binary and ternary blends of biodiesel of soybean, rapeseed and palm, and diesel fuel were prepared and its dynamic viscosities and densities were measured in function of temperature. Mixing rules are used for predicting the densities and viscosities from pure compounds. The low temperature behaviour of three biodiesel was studied. The liquid and solid phase compositions and solid fraction at temperatures below the cloud point were analyzed. A thermodynamic model was applied to describe these multiphase systems and other similar systems. Two versions of the predictive UNIQUAC model along with an approach that assuming complete immiscibility of the compounds in the solid phase are evaluated against the experimental phase equilibrium data measured.

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27

Valverde, Marlen A. "Green plastics, rubbers, coatings, and biocomposites from vegetable oils." [Ames, Iowa : Iowa State University], 2009. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3389154.

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28

McGill, Jeremy Parker Firman Jeffre D. "Effect of high peroxide value fats on performance of broilers in normal and immune challenged states." Diss., Columbia, Mo. : University of Missouri--Columbia, 2009. http://hdl.handle.net/10355/6471.

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Title from PDF of title page (University of Missouri--Columbia, viewed on Feb 18, 2010). The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Thesis advisor: Dr. Jeffre D. Firman. Includes bibliographical references.

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29

Roy, Dibakar. "Modification of vegetable oils as a potential base oil and a multifunctional lube oil additive." Thesis, University of North Bengal, 2021. http://ir.nbu.ac.in/handle/123456789/4365.

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30

Morlok, Kathleen M. "Food scientist's guide to fats and oils for margarine and spreads development." Manhattan, Kan. : Kansas State University, 2010. http://hdl.handle.net/2097/4205.

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31

Lambert, Marc S. "Hepatic metabolism of chylomicron remnants derived from different dietary oils and fats." Thesis, Royal Veterinary College (University of London), 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.522619.

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32

Barton, Paul. "Enhancing separation of fats, oils and greases (FOGs) from catering establishment wastewater." Thesis, Cranfield University, 2012. http://dspace.lib.cranfield.ac.uk/handle/1826/8052.

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Removal of fats, oils and greases (FOG) from commercial food premises prior to discharge of wash waters into the sewer is critical in restricting blockage events. The FOG droplets that form are commonly removed in passive gravity separators. Enhanced separation through design modification, would allow a reduction in size required to achieve target removal. The aim of the project was to determine the feasibility of enhancing removal of FOGs in gravity separation devices and or in post treatment units. The thesis work examined the effect characteristics of oil droplet size and density had on FOG removal with a view to increasing droplet rise rates and hence separation. Examination of kitchen wastewater from a number of restaurants established that droplet sizes were typically in the mechanically emulsified oil size range, often with high zeta potential indicating electrostatic stabilisation of suspensions. Oil removal rates were examined using different oils typical of food preparations in laboratory scale experiments. Under a fixed energy input the different oils produced different droplet size distributions such that very different separation efficiencies were observed. The removal rates obtained allowed the prediction of oil removal from a sample in a given time when the median droplet size and density of the oil were known. For effective understanding of separator design and testing, droplet densities and sizes must be adequately measured and replicated. In addition, the light fuel oil used in the certification test produced very unstable suspensions, easily separable in the standard testing conditions, proving it a poor surrogate test material. Pre-formed droplets of sunflower oil were treated in a vertically aligned reaction chamber with an ultrasonic transducer fitted at the base. FOG removal, measured as HEM removal, was monitored as a function of power input, frequency, reactor size and residence time, the incoming flow entered counter currently to the ultrasonic wave propagation. The ultrasound treatment procedure removed 80% of oil from a suspension of droplets in the mechanically emulsified oil size range during the course of a 54 minute continuous experiment compared to 20-30% removal in the case of an equivalent separated without ultrasonic enhancement. The enhanced separation was found to be dependent on the power input and the reactor size. Application of ultrasound energy in modified grease separators to remove short-circuiting droplets would allow a reduction in overall size of units through reduced residence time requirement.

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Bailie, Pamela M. "An investigation into the hydrolysis of fats and oils using immobilised lipases." Thesis, Queen's University Belfast, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.286852.

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Sadeghi-Jorabchi, Houtan. "The development of vibrational spectroscopy for the analysis of fats and oils." Thesis, University of East Anglia, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.303016.

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Morlok, Kathleen M. "Food scientist’s guide to fats and oils for margarine and spreads development." Kansas State University, 2010. http://hdl.handle.net/2097/4205.

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Master of Science Food Science Institute - Animal Science & Industry Kelly J. K. Getty Fats and oils are an important topic in the margarine and spreads industry. The selection of these ingredients can be based on many factors including flavor, functionality, cost, and health aspects. In general, fat is an important component of a healthy diet. Fat or oil provides nine calories per gram of energy, transports essential vitamins, and is necessary in cellular structure. Major shifts in consumption of fats and oils through history have been driven by consumer demand. An example is the decline in animal fat consumption due to consumers’ concern over saturated fats. Also, consumers’ concern over the obesity epidemic and coronary heart disease has driven demand for new, lower calorie, nutrient-rich spreads products. Fats and oils can be separated into many different subgroups. “Fats” generally refer to lipids that are solid at room temperature while “oils” refer to those that are liquid. Fatty acids can be either saturated or unsaturated. If they are unsaturated, they can be either mono-, di-, or poly-unsaturated. Also, unsaturated bonds can be in the cis or trans conformation. A triglyceride, which is three fatty acids esterified to a glycerol backbone, can have any combination of saturated and unsaturated fatty acids. Triglycerides are the primary components of animal and vegetable fats and oils. The ratio of saturated to unsaturated fatty acids in these fats and oils has a great impact on their functionality. Common fats and oils include butterfat, beef tallow, fish oils, soybean oil, rapeseed (canola) oil, corn oil, cottonseed oil, olive oil, sunflower oil, palm oil, palm kernel oil, coconut oil, linseed (flax) oil, and safflower oil. Typical fat and oil modification techniques include hydrogenation, interesterification, alternative hydrogenation, fractionation, blending, farm/field practices and genetic modification, and the use of fat replacers. There are many processing techniques that can be utilized in margarine and spreads production. The process can be optimized for each margarine or spreads product. There are many fats and oils in margarine and spreads formulations. Familiarity with commonly used fats and oils in regards to availability, cost, nutrition, chemistry, and functionality are important when creating a cost-effective, functional margarine or spreads product.

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Lunnbäck, Johan. "Hydrodynamic cavitation applied to anaerobic degradation of fats, oils and greases (FOGs)." Thesis, Linköpings universitet, Tema Miljöförändring, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-140685.

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To increase profitability for biogas production, new innovative substrates and condition of operations needs to be implemented. At the current state, fats, oils and greases (FOGs) represent a promising substrate even though it brings operational challenges to the anaerobic digestion process. By utilizing hydrodynamic cavitation (HC) as a pre-treatment of the FOGs, the efficiency of FOGs’ co-digestion with wastewater sludge can be significantly improved. Preliminary experiments conducted on oil and water demonstrates that the HC pre-treatment improves the oil solubilisation as well as forms stable oil and water emulsion that last for several hours. The pre-treatment also improved the soluble chemical oxygen demand (COD) of biosludge (BiSl) by up to 115% and the initial degradation rate by up to 35%. In a semi-continues system, this allowed a significant increment in the specific methane yield depending on the organic loading rate (OLR) applied1. With sufficient process optimization, the HC-pre-treatment may prove to be an energy efficient and effective pre-treatment of FOGs.

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Stewart, David I. "The effect of low melting oils on the crystallisation of confectionery fats." Thesis, Loughborough University, 2017. https://dspace.lboro.ac.uk/2134/24420.

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This thesis concentrates on gaining a fundamental understanding of the crystallisation, phase behaviour, and melting in relatively simple fat/oil blends. This is the first reported study of hot stage microscopy (HSM) experiments on tripalmitin (PPP)/triolein (OOO), 1,3-dipalmitoyl-2-oleoylglycerol (POP)/OOO, and cocoa butter (CB)/hazelnut oil (HZ) systems. The HSM technique allows the visualisation of the initial crystallisation, polymorphic transformations, and melting of fat crystals; melting points can also help identify polymorphic form. Supporting experiments were also performed using differential scanning calorimetry (DSC), nuclear magnetic resonance (NMR), and X-ray diffraction (XRD). In PPP-OOO samples, HSM visualised for the first time a melt-mediated transformation from β' to β across a small liquid gap between the untransformed (β') and transformed (β) material. This behaviour was not seen with pure PPP. Melting points obtained by HSM for the PPP/OOO system were above those predicted by the Hildebrand equation, but this is attributed to the non-equilibration of concentration gradients within the system. This was evidenced by the fact that a rapid cooling rate (to produce a finer microstructure with smaller crystals, and hence reduce diffusion distances) combined with a slower remelt rate enabled samples to melt close to ideal. Indeed, final melting points obtained via HSM were consistently higher than DSC results across all systems; convection and the more three-dimensional system in DSC (as compared with the two-dimensional HSM system) may have aided melting. The POP/OOO system displayed complex remelting behaviour, especially when warmed at a relatively slow rate; this also resulted in a higher production of β. Liquid oil content was shown to not only be important in aiding transformation of lower forms to β, but also reduced the number of polymorphs observed upon remelting, as compared with pure fat samples. Liquid oil content was also shown to be crucial for transformation to β in the CB/HZ experiments; very few β crystals were seen in pure CB samples. Experiments carried out on DSC for both CB and CB-HZ cooling at 1°C/min or faster produced both α and β' crystals, but for CB-HZ this also then led to some transformation from α to β. The β polymorph was not observed when only β' was formed at slower cooling rates. A curious result was that the effect was stronger the longer the samples were held at 0°C before rewarming, with the α becoming more resilient against transforming to β' and instead transforming directly to β. More extensive transformation to β occurred if the sample was held for 30 min at 18°C or 22°C during the rewarming step. As well as showing differences in melting temperatures, the HSM and DSC results also did not always match with respect to polymorphic form. Small quantities of β crystals were seen in HSM samples that were not always seen in thermograms of equivalent DSC samples. This either highlights the limitations of DSC or suggests that polymorphic behaviour in the more fluid DSC system differs to that in HSM, or both. Growth rate analysis of PPP (in OOO) showed that both reduced supersaturation and supercooling can be correlated with the growth rates of β' and β. Growth rates of β that occurred via the melting of β' were well correlated with driving forces that took into account that the concentration of PPP in the liquid gap between β' and β (from which the β crystal was growing) was limited by the solubility of β' at the sample temperature. Whilst temperature is often seen as a key driver in governing polymorphic transformation, part of the temperature effect may be an indirect effect via the extra amount of liquid content at higher temperatures. The ability of oil to aid transformation to β may be relevant to food systems where this higher polymorphic form is the preferred type, such as chocolate. Potential applications could include producing novel fat blends with relatively stable fat network structures at a lower overall saturate level, or developing blends with bloom inhibiting properties.

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Good, Joanne Elizabeth. "Replacement of dietary fish oil with vegetable oils : effects on fish health." Thesis, University of Stirling, 2004. http://hdl.handle.net/1893/2005.

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The work presented in this thesis examined the effects of dietary fish oil replacement on fish innate and adaptive immune function, disease resistance tissue histopathology and fatty acid composition of lipids in peripheral blood leukocytes. Dietary trials with Atlantic salmon (Salmo salar), Sea bass (Dicentrarchus labrax), Atlantic cod (Gadus morhua) and Arctic char (Salvelinus alpinus) were conducted in which fish oil was replaced by rapeseed oil, linseed oil, olive oil, palm oil, echium oil or a mixture of these oils. A significant reduction in respiratory burst activity was most pronounced in salmon and sea bass fed high levels of rapeseed oil-containing diets. In addition, rapeseed and olive oil inclusion in the diets of salmon and sea bass significantly reduced the head kidney macrophage phagocytic capacity to engulf yeast particles. A reduction in prostaglandin E2 levels was found to be related to a reduction in macrophage respiratory burst activity in salmon fed linseed oil diets and sea bass fed a dietary blend of linseed, palm and rapeseed oils. Changes in macrophage function may be a contributing factor causing a reduction in serum lysozyme activity observed in some trials. No significant differences were detected in cumulative mortality of Atlantic salmon fed an equal blend of linseed and rapeseed oils challenged with Aeromonas salmonicida. However, resistance to Vibrio anguillarium was significantly impaired in Atlantic salmon fed a blended oil diet containing linseed, rapeseed and palm oil. The major histological difference of fish fed vegetable oil diets was the accumulation of lipid droplets in their livers. Dietary fatty acid composition significantly affected the fatty acid composition of peripheral blood leukocytes. Generally, fish fed vegetable oil diets had increased levels of oleic acid, linoleic acid and a-linolenic acid and decreased levels of eicosapentaenoic acid, docosahexaenoic acid and a lower n-3/n-6 ratio than fish fed a FO diet. In conclusion, the results from these studies suggest that farmed fish species can be cultured on diets containing vegetable oils as the added oil source. However, feeding high levels of some vegetable oils may significantly alter some immune responses in the fish, especially head kidney macrophage function, disease resistance and, in addition, may cause an increase in tissue histopathology.

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Chan, Yip-wai Edward. "A preliminary study on cooking oil waste management in Hong Kong /." Hong Kong : University of Hong Kong, 1998. http://sunzi.lib.hku.hk/hkuto/record.jsp?B2012613X.

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He, Hanping, and 何漢平. "Oil and squalene in Amaranthus." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2003. http://hub.hku.hk/bib/B31244191.

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Lopes, Shailesh M. "Evaluation of fats and oils & their derivatives as potential phase change materials (PCM) for thermal energy storage /." free to MU campus, to others for purchase, 2003. http://wwwlib.umi.com/cr/mo/fullcit?p1418045.

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42

Park, Jonathan S. B. "An investigation of the reactions of nitric oxide with selected organic compounds." Thesis, University of St Andrews, 1996. http://hdl.handle.net/10023/14897.

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The reaction of nitric oxide (NO) with several organic and model biological compounds was studied to determine the ultimate fate of NO in a biological milieu, and to devise novel methods of trapping and analysing NO. A series of potential spin traps including anthracene, o-quinone and 2- acetylcyclohexanone was investigated by bubbling NO through a solution of the above compounds. The resulting mixture was analysed by EPR spectroscopy and GC-MS. The EPR spectra obtained showed no radicals were produced and GC-MS analysis revealed only unreacted starting material. Dienes were investigated because of their willingness to react with radical species. Trans-1,4-diphenyl-1,3-butadiene did not form a nitroxide when reacted with NO, but in the presence of molecular oxygen, 2,5-dimethyl-2,4-hexadiene gave a mixture of a di-t-alkyl nitroxide and a t-s-dialkyl nitroxide. Traps related to nitromethane anion were investigated in basic solution to generate the aci form, but the only compound to give a spin adduct was nitroethane, and this did not give the expected EPR spectrum. 2-Diazocycloheptanone was synthesised from cycloheptanone and reacted with NO. This reaction produced E and Z iminoxyl radicals and a carbonyl nitroxide. When the solvent was changed from t-butyl benzene to water, no reaction was observed. A known NO donor, S-nitroso-N-acetyl penicillamine (SNAP), was mixed with the spin trap and photolysed, but this did not produce a spin adduct. A second diazo compound, 5-diazouracil, was investigated, and this produced a radical species with complex but weak EPR spectra. Nitric oxide was reacted with stable free radicals to provide a quantitative spectrophotometric test for NO. Tetraphenylhydrazine was prepared which is in equilibrium with the diphenylaminyl radical in solution. The diphenylaminyl radical trapped NO and was detected by UV/vis spectroscopy, reaching a λ[sub]max after about one hour. When the solvent was changed from t-butyl benzene to acetonitrile, the reaction took place much more rapidly. From these results it appeared that NO could be detected at concentrations beteween 10 −4 and 10−7 M. Nitric oxide did not react with the parent compound, diphenylamine. When mixed with NO2, diphenylamine formed nitro addition products. Another stable radical, galvinoxyl, was investigated. This did not rapidly scavenge NO to give an identifiable adduct. Nitric oxide was reacted with several alkenes with electron-releasing groups and alkenes with electron-withdrawing groups. The reaction between n-butylvinyl ether and NO was investigated at room temperature. Many oxidation products were identified from the mass spectra obtained. Oxidation products were also identified from the reaction between NO and 1-cyclohexenyIoxytrimethylsilane. Analysis by EPR spectroscopy revealed the presence of two radicals, likely to be dialkyl nitroxides. No products were observed in the reaction of NO and methyl linoleate. EPR spectroscopy of a solution containing mesityl oxide and NO revealed the presence of three radicals, E and Z conformers of the iminoxyl radical, and a carbonyl nitroxide. 1-Acetylcyclohexene reacted with NO to give a di-t-alkyl nitroxide. Synthesis and subsequent photolysis of 1-acetylcyclohexenyl oxime confirmed this result. Another acceptor compound studied was tetracyanoethene; this did not react with NO. Cyclopropylacetyl peroxide was investigated, as decomposition gives the cyclopropyl methyl radical. Analysis of the resulting solution showed that bicyclohexyl had been formed, but there were no traces of any nitrogen-containing products. Nitric oxide did not react with either glutathione or dibenzyl disulphide, but NO2 reacted with L-tryptophan forming a radical adduct. Analysis by EPR spectroscopy yielded a strong three-line signal, characteristic of a nitroxide. The abstraction of hydrogen from, and the rearrangement of selected silylamines was investigated. The amines were photolysed in the presence of di-t-butyl peroxide in the cavity of the EPR spectrometer at temperatures ranging from 160K to 250K. The spectra obtained showed the unrearranged and rearranged radicals. No nitrogen-centred radicals were observed by EPR.

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Myint, Lay L. "Process analysis and optimization of biodiesel production from vegetable oils." [College Station, Tex. : Texas A&M University, 2007. http://hdl.handle.net/1969.1/ETD-TAMU-1267.

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Gamage, Padmasiri Kankanam. "Use of selected vegetable oils as plasticiser/stabiliser for PVC." Thesis, London Metropolitan University, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.507082.

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Hu, Chaohe. "Versatile biobased particles of acrylate vegetable oils : Synthesis and applications." Thesis, université Paris-Saclay, 2022. http://www.theses.fr/2022UPAST081.

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Depuis ses débuts, au début des années 1920, l'industrie des polymères dépend fortement des ressources en combustibles fossiles. Environ 4 à 8 % du pétrole, du gaz et de leurs dérivés sont aujourd'hui transformés en matériaux polymères. La plupart d'entre eux sont non recyclables et non dégradables, ce qui entraîne de graves problèmes environnementaux, préjudiciables à la faune et à l'homme. Dans ce contexte, il est nécessaire de développer des produits polymères alternatifs qui, à partir de matières premières renouvelables, présenteront le même niveau de complexité que les produits actuels issus de l'industrie pétrolière.Parmi les différentes matières premières biosourcées utilisées pour fabriquer des matériaux polymères, les huiles végétales sont prometteuses pour leur faible coût et leur dégradabilité intrinsèque, mais aussi parce que leur production est déjà optimisée pour l'industrie alimentaire. L'huile de soja époxydée acrylée (AESO) est un exemple des dérivés d'huiles végétales qui sont utilisés comme additifs plastifiants pour la formulation du PVC. Seule, l'AESO peut être facilement et rapidement polymérisée pour donner un polymère thermodurci. Cependant, en raison de sa viscosité intrinsèque élevée, la plupart des recherches sur les polymères à base d'AESO se sont concentrées jusqu'à présent sur les propriétés de masse, de revêtement ou de film de ce matériau, laissant dans l'ombre la possibilité de fabriquer des matériaux à haute valeur ajoutée.Ce travail se concentre sur la fabrication et l'application des microparticules d'AESO. Nous présentons d'abord une approche simple à travers un mélangeur vortex pour préparer les particules AESO polydispersées basées sur la photopolymérisation en émulsion. Les microparticules AESO synthétisées présentent une bonne dégradabilité dans des conditions chimiques et enzymatiques. Ensuite, nous développons un dispositif microfluidique " one pot " avec une structure de focalisation du flux pour l'émulsification et une zone serpentine pour la réticulation induite par les UV, qui peut être utilisé pour produire en continu des particules AESO monodispersées avec une taille réglable. Nous démontrons également la méthode basée sur les puces microfluidiques modifiées pour préparer les particules non sphériques, où une puce avec une jonction de focalisation d'écoulement en forme de Y est utilisée pour préparer les particules AESO en forme de croissant et une autre puce avec une double jonction de focalisation d'écoulement est utilisée pour synthétiser les particules AESO structurées en coquille de trou. De plus, des microcapsules d'AESO sont fabriquées par la puce personnalisée et elles sont disponibles pour encapsuler des solutions ou des substances aqueuses. Enfin, nous montrons la capacité des microparticules AESO à transporter les molécules organiques dans leurs réseaux réticulés et utilisons des méthodes similaires pour charger les médicaments (curcumine et ibuprofène). Le comportement de libération des médicaments dans le fluide corporel simulé peut être observé, ce qui peut constituer un support prometteur pour d'autres applications pharmaceutiques Since its beginning, in the early 1920's, polymeric industry relies heavily on fossil fuel resources. Approximately 4%-8% oil, gas and their derivatives are nowadays transformed into polymeric materials. Most of them are non-recyclable and non-degradable, hence leading to serious environmental issues, detrimental to wildlife and humans. In this context, there is a need for the development of alternative polymeric products, which, starting from renewable commodities, will share the same level of complexity than current ones derived from oil industry.Among the various bio-sourced raw products used to make polymeric materials, vegetable oils are promising for their low cost and intrinsic degradability, but also because their production is already optimized for the food industry. Acrylated epoxidized soybean oil (AESO) is one example of the vegetable oil derivatives that are used as e.g. plastifying additives for the formulation of PVC. Alone, AESO can be readily and rapidly polymerized to give a thermoset polymer. However, as a consequence of its high intrinsic viscosity, most of the research on AESO-based polymer so far is only focused on the bulk, coating or film properties of this material, leaving the possibility to fabricate high added value materials a blind spot.Herein, this work focuses on the fabrication and application of the AESO microparticles. We first present a simple approach through a vortex mixer to prepare the polydispersed AESO particles based on the emulsion photopolymerization. The synthesized AESO microparticles present a good degradability in the chemical and enzymatic conditions. Then, we develop a “one pot” microfluidic device with a flow-focusing structure for emulsification and the serpentine zone for UV-induced reticulation, which can be used to continuously product the monodispersed AESO particles with a tunable size. We also demonstrate the method base on the modified microfluidic chips to prepare the non-spherical particles, where a chip with Y-shape flow-focusing junction is used to prepare the crescent-shaped AESO particles and another chip with a double flow-focusing junction is utilized to synthesize the hole-shell structured AESO particles. In addition, AESO microcapsules are fabricated by the customized chip, and they are available to encapsulate the aqueous solutions or substances. Finally, we show the ability of AESO microparticles to carry the organic molecules into their crosslinked networks and use the similar methods to load the drugs (curcumin and ibuprofen). The release behavior of drugs in simulated body fluid can be observed, which may be act as a promising drug carrier for further pharmacy applications

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Piccolo, Damiano. "Epoxidation of vegetable oils by conventional and non-conventional methods." Doctoral thesis, Università degli studi di Padova, 2020. http://hdl.handle.net/11577/3425915.

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The interest on epoxidised vegetable oils has been increasing in the last years thanks to their use as renewable and sustainable resource for a wide range of environmental-friendly and sustainable chemicals. The aim of this work is producing epoxidised soybean oil in newer, safer and more efficient ways. This PhD thesis is structured according to different experimental approaches, supported by a kinetic and mass transfer modelling to enable a complete understanding of the phenomena. The epoxidation process was carried out in two phases via peroxyacetic acid, produced by the reaction between acetic acid and hydrogen peroxide. Epoxidation of soybean oil was carried out in a batch calorimetric reactor, for an accurate study on kinetics, mass transfer and calorimetry. Furthermore, the microwave (MW) heating effect on the process was studied, by means of a comparative study using two geometrically similar reactors with different heating sources, conventional and MW heating. MW heating process is able to produce a uniform stable suspension halving the time to reach maximum yield. Epoxidation was tested also in a continuous system, for its potential industrial interest. The process was also effective in a continuous reactor, even though the mixture must be stabilised by means of a surfactant. The feasibility of using radiofrequency heating in the continuous reactor was tested for more controlled operation than MW heating.

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Gibert, Casamada Anna. "The utilization of filled milk in the manufacture of yogurt." Thesis, University of Lincoln, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.262208.

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Kalu, Clara U. U. "A chemical and organoleptic assessment of autoxidising oils." Thesis, Liverpool John Moores University, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.262066.

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Mursi, Eltigani Sidahmed. "Accelerated test methods for determination of the oxidative stability of oils and fats." Thesis, University of Reading, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.315355.

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50

Green, Travis. "An impact analysis on how biodiesel demand affects the fats and oils market." Diss., Columbia, Mo. : University of Missouri-Columbia, 2008. http://hdl.handle.net/10355/5642.

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Thesis (M.S.)--University of Missouri-Columbia, 2008. 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 August 12, 2009) Includes bibliographical references.

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Dissertations / Theses on the topic 'Vegetable oils and fats'

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