Ho, Wing Ho. / On t.p. "beta" appears as the Greek letter. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 157-183). / Abstracts in English and Chinese. / Thesis committee --- p.ii / Statement --- p.iii / Acknowledgements --- p.iv / Abstract --- p.vi / 摘要 --- p.vii / Table of Contents --- p.viii / List of Tables --- p.xv / List of Figures --- p.xvii / List of Abbreviations --- p.xxiii / Chapter Chapter 1 --- General Introduction --- p.1 / Chapter Chapter 2 --- Literature Review --- p.4 / Chapter 2.1 --- Vitamin A --- p.4 / Chapter 2.1.1 --- Genral and properties --- p.4 / Chapter 2.1.2 --- Biological importance of vitamin A --- p.6 / Chapter 2.1.3 --- Dietary source of vitamin A --- p.12 / Chapter 2.1.3.1 --- Plant-derived provitamin A and animal-derived vitamin A --- p.12 / Chapter 2.1.3.2 --- Dependence on the plant-derived provitamin A by the poor --- p.14 / Chapter 2.1.3.2.1 --- Plant-derived provitamin A --- p.14 / Chapter 2.1.3.2.1.1 --- General and properties --- p.14 / Chapter 2.1.3.2.1.2 --- Biosynthesis of provitamin A in plants --- p.17 / Chapter 2.1.3.2.1.2.1 --- Assembly of C40 backbone … --- p.17 / Chapter 2.1.3.2.1.2.2 --- Desaturation and cyclization --- p.26 / Chapter 2.1.3.2.1.2.3 --- Oxygenation --- p.29 / Chapter 2.1.3.2.1.2.4 --- Carotenogenic enzymes --- p.31 / Chapter 2.1.4 --- Metabolism of dietary vitamin A and provitamin A in human system --- p.35 / Chapter 2.1.4.1 --- Digestion and absorption --- p.35 / Chapter 2.1.4.2 --- Biocon version --- p.37 / Chapter 2.1.4.2.1 --- "Beta, beta '-carotene 15, 15'-monooxygenase (BCMO)" --- p.40 / Chapter 2.1.4.3 --- "Transport, uptake and storage" --- p.43 / Chapter 2.1.4.4 --- Provision or excretion --- p.46 / Chapter 2.2 --- Vitamin A deficiency (VAD) --- p.48 / Chapter 2.2.1 --- Green revolution --- p.48 / Chapter 2.2.2 --- Rice as the major staple food for feeding the poor --- p.49 / Chapter 2.2.3 --- Provitamin A content in processed rice seeds --- p.49 / Chapter 2.2.4 --- Symptoms of VAD --- p.51 / Chapter 2.2.5 --- Global prevalence of VAD --- p.53 / Chapter 2.3 --- Previous efforts for dealing with the deficiency --- p.55 / Chapter 2.3.1 --- The key for dealing with the deficiency --- p.55 / Chapter 2.3.2 --- Selective plant breeding --- p.55 / Chapter 2.3.3 --- Supplementation and post-harvesting fortification --- p.56 / Chapter 2.3.4 --- Bio-fortification by genetic engineering --- p.57 / Chapter 2.3.4.1 --- Advantages of genetic engineering --- p.57 / Chapter 2.3.4.1.1 --- Genetic engineering of non-cereal crops --- p.58 / Chapter 2.3.4.1.2 --- Genetic engineering of cereal crops --- p.62 / Chapter 2.3.4.1.2.1 --- Golden Rice 1 --- p.62 / Chapter 2.3.4.1.2.2 --- Golden Rice 2 --- p.64 / Chapter 2.4 --- Motivation for striking forward --- p.67 / Chapter 2.4.1 --- Recommended Dietary Amount of vitamin A --- p.67 / Chapter 2.4.2 --- Factors affecting the bioefficacy of provitamin A in human body --- p.68 / Chapter 2.4.2.1 --- Bioavailability --- p.68 / Chapter 2.4.2.2 --- Bioconvertibility --- p.69 / Chapter 2.4.2.3 --- Health and nutritional status --- p.71 / Chapter 2.4.3 --- Further improvement for dealing with the deficiency --- p.73 / Chapter 2.5 --- Hypothesis --- p.75 / Chapter Chapter 3 --- Materials and Methods --- p.78 / Chapter 3.1 --- Chemicals --- p.78 / Chapter 3.2 --- Bacterial strains --- p.78 / Chapter 3.3 --- Transient expression of BCMOs in plant system --- p.79 / Chapter 3.3.1 --- Choice of BCMOs --- p.79 / Chapter 3.3.2 --- Plasmids and genetic material --- p.79 / Chapter 3.3.3 --- Construction of chimeric genes for transient expression --- p.82 / Chapter 3.3.4 --- Microprojectile bombardment and GUS assay --- p.83 / Chapter 3.4 --- Construction of chimeric genes for rice co-transformation --- p.84 / Chapter 3.4.1 --- Choice of carotenogenic genes --- p.84 / Chapter 3.4.2 --- Choice of promoters --- p.84 / Chapter 3.4.3 --- Necessities and choice of transit peptide (TP) --- p.85 / Chapter 3.4.4 --- Arrangement of chimeric gene-cassettes --- p.86 / Chapter 3.4.5 --- Plasmids and genetic materials --- p.87 / Chapter 3.4.6 --- Construction of chimeric gene expressing PSY and PDS coordinately --- p.87 / Chapter 3.4.7 --- "Construction of chimeric gene expressing PSY, PDS and TP equipped CHBCMO coordinately" --- p.92 / Chapter 3.4.8 --- "Construction of chimeric gene expressing PSY, PDS and TP equipped ZEBCMO coordinately" --- p.98 / Chapter 3.4.9 --- Construction of chimeric gene expressing ZDS and LYCB coordinately --- p.103 / Chapter 3.4.10 --- Confirmation of sequence fidelity --- p.108 / Chapter 3.5 --- Rice co-transformation --- p.109 / Chapter 3.5.1 --- Plant materials --- p.109 / Chapter 3.5.2 --- Preparation of Agrobacterium tumefaciens --- p.109 / Chapter 3.5.3 --- Agrobacterium mediated co-transformation --- p.110 / Chapter 3.5.3.1 --- Callus induction from mature rice seeds --- p.110 / Chapter 3.5.3.2 --- Callus induction from immature rice seeds --- p.110 / Chapter 3.5.3.3 --- "Co-cultivation, selection and regeneration" --- p.111 / Chapter 3.6 --- Detection of transgene expression --- p.112 / Chapter 3.6.1 --- Detection at DNA level --- p.112 / Chapter 3.6.1.1 --- Genomic DNA extraction --- p.112 / Chapter 3.6.1.2 --- PCR screening --- p.112 / Chapter 3.6.1.3 --- Synthesis of DIG-labeled DNA probes --- p.114 / Chapter 3.6.1.4 --- Southern blot analysis --- p.115 / Chapter 3.6.2 --- Detection at RNA level --- p.116 / Chapter 3.6.2.1 --- Total RNA extraction --- p.116 / Chapter 3.6.2.2 --- Northern blot analysis --- p.116 / Chapter 3.6.3 --- Detection at product level --- p.117 / Chapter 3.6.3.1 --- Phenotypic identification --- p.117 / Chapter 3.6.3.2 --- HPLC analysis --- p.117 / Chapter 3.6.3.2.1 --- Extraction of total carotenoids and retinoids --- p.117 / Chapter 3.6.3.2.2 --- HPLC identification --- p.118 / Chapter 3.6.3.2.3 --- HPLC quantification --- p.118 / Chapter Chapter 4 --- Results --- p.119 / Chapter 4.1 --- Transient expression of BCMOs in plant system --- p.119 / Chapter 4.1.1 --- Construction of chimeric genes for transient expression --- p.119 / Chapter 4.1.2 --- Microprojectile bombardment and GUS assay --- p.120 / Chapter 4.2 --- Construction of chimeric genes for rice co-transformation --- p.121 / Chapter 4.3 --- Rice co-transformation --- p.123 / Chapter 4.3.1 --- Callus induction from mature and immature rice seeds --- p.123 / Chapter 4.3.2 --- "Co-cultivation, selection and regeneration" --- p.124 / Chapter 4.4 --- Detection of transgene expression --- p.126 / Chapter 4.4.1 --- Detection at DNA level --- p.126 / Chapter 4.4.1.1 --- PCR screening --- p.126 / Chapter 4.4.1.2 --- Southern blot analysis --- p.129 / Chapter 4.4.2 --- Detection at RNA level --- p.133 / Chapter 4.4.2.1 --- Northern blot analysis --- p.133 / Chapter 4.4.3 --- Detection at product level --- p.135 / Chapter 4.4.3.1 --- Phenotypic identification --- p.135 / Chapter 4.4.3.2 --- HPLC identification --- p.137 / Chapter 4.4.3.3 --- HPLC quantification --- p.147 / Chapter Chapter 5 --- Discussion --- p.150 / Chapter Chapter 6 --- Conclusion --- p.156 / References --- p.157

No description available.

A utilização de bioativos naturais como ingredientes está em constante expansão na indústria alimentícia, devido ao aumento das exigências pelos consumidores por alimentos mais saudáveis. Por isso, há uma busca constante de tecnologias que possibilitem a incorporação de tais substâncias em alimentos. O β-caroteno é uma substância hidrofóbica, cujos benefícios estão relacionados principalmente à sua ação antioxidante. Devido à sua característica hidrofóbica, a utilização deste pigmento implica em desafios tecnológicos para ser incorporado em formulações alimentícias de base aquosa. Por este motivo, a encapsulação em lipossomas pode ser uma ótima alternativa, devido à capacidade de englobar tais substâncias em sua bicamada lipídica. Além da proteção, essas matrizes encapsulantes podem proporcionar a liberação controlada dos ingredientes encapsulados, bem como aumento de sua biodisponibilidade. O objetivo deste trabalho foi produzir e caracterizar dispersões de lipossomas encapsulando β-caroteno estabilizadas com a adição de hidrocolóides(goma xantana ou mistura de goma xantana e goma guar). O diâmetro médio hidrodinâmico, a distribuição de tamanho das partículas e a morfologia foram avaliadas. Os lipossomas produzidos foram vesículas multilamelares (MLV), as distribuições de tamanho dos lipossomas apresentaram-se heterogêneas e as micrografias revelaram a forma esférica dos lipossomas dispersos no meio aquoso, assim como a integridade da sua bicamada lipídica. Foram realizadas análises de quantificação do β-caroteno e colorimetria instrumental, sendo que todas as dispersões mostraram-se eficientes na preservação do β-caroteno ao longo do período de armazenamento. Os hidrocolóides adicionados foram eficazes no aumento da viscosidade da fase contínua, evitando a agregação das vesículas ao longo do tempo, exceto para dispersão estabilizada com a mistura de goma xantana e goma guar, com 0,15% de goma total. Em relação à adição das dispersões de lipossomas em iogurte, as formulações mostraram-se homogêneas, com ausência de grumos ou qualquer tipo de separação de fases, e também foram aprovados por uma parcela de painelistas na análise sensorial. / The use of natural bioactives as ingredients is in constant expansion in the food industry, due to increasing consumer demands for healthier foods. Therefore, there is a constant search for technologies capable of incorporating such substances in food. β-carotene is a hydrophobic substance, whose benefits are mainly related to its antioxidant action. Because of its hydrophobic characteristics, the use of this pigment implies technical challenges to be incorporated into aqueous-based food formulations. For this reason, encapsulation in liposomes may be a good alternative, because of their ability to incorporate such substances in their lipid bilayer. Besides the protection, these encapsulants matrix can provide controlled release of the encapsulated ingredients, as well as increasing its bioavailability. The objective of this study was to produce and characterize dispersions of liposomes encapsulating β-carotene, which were stabilized with the addition of hydrocolloids: xanthan gum or a mixture of xanthan gum and guar gum. The mean hydrodynamic diameter, distribution of particle size and its morphology were studied. The obtained dispersions were multilamellar vesicles (MLV), the liposomes size distributions were heterogeneous and the micrographs revealed the liposomes spherical shape dispersed in aqueous medium, as well as the integrity of their lipid bilayer. The quantification of β-carotene and instrumental colorimetry analyses indicated the liposomes were efficient in the preservation of β-carotene during the storage period. The hydrocolloids added in the dispersions were highly efficient to increase the viscosity of the continuous phase. Therefore, the hydrocolloids were responsible for the prevention of aggregation of the vesicles during the storage period, except for stabilized dispersion with the mixture of xanthan gum and guar gum, with 0.15% gum total. Regarding the dispersions of liposomes added in yoghurt, the formulations were homogeneous, with absence of lumps or any phase separation, and also have been approved by a significant number of the panelists.

Alfalfa is Generally regarded as one of the world's most valuable cultivated forage crops. Few crops, if any, are equal to it in capacity to produce heavy yields of highly nutritious, palatable feed. A combination of desirable attributes as a forage plant and adaptation to a wide diversity of soil and climatic conditions has led to the use of alfalfa in the world to an extent probably exceeding that of any other single legume or grass. Alfalfa constantly proves itself as a valuable feed for most types of livestock. This is especially true in the states where a large amount of hay is harvested and stored for the wintering of livestock, and where it is dehydrated, ground and incorporated into poultry rations. As better methods are developed for the harvesting, handling and storage of alfalfa so as to retain maximum nutrient value, its importance will constatly increase. The nutrient value of the hay may be influenced by the variety of alfalfa grown as shown by Thompson (1949) and the fertility level of the soil as shown by several authors encluding Barakat (1950), kashemsri (1952) and Jones (1953). Because of alfalfa's growing importance it is desirable to determine the most economical methods of producing maximum yields of hay with high nutritive value.

Molecules of anthocyanins and quinones possess distinctive electrophilic character, which is demonstrated by their facile reactions with nucleophiles such as sulfite, thiols, amines and water. In food systems, one of their likely targets would be nucleophilic centers in the side chains of amino acids. Our experiments revealed that on a short-term exposure (1 72 h) to free amino acids in solutions with pH < 7 glycosides of cyanidin and quinones of phenolic acids did not yield nucleophilic addition products with most of the amino acids. A notable exception was cysteine, which reacted with oxidized phenolic acids and caused anthocyanin bleaching at elevated temperature. Thermodynamic aspects of the nucleophilic addition reactions were investigated with the aid of computational chemistry. We have also found that enzymatic browning in apricot puree does not lead to trans-cis -carotene isomerization, contrary to some previous reports. Increased availability of -carotene for extraction was recorded for browned apple- and pear-apricot purees in comparison with the non-browned purees. / Food Science and Technology

Thesis (M.S.)--University of Hawaii at Manoa, 2004. / Includes bibliographical references (leaves 67-84). Also available via World Wide Web.

No description available.

A utilização de bioativos naturais como ingredientes está em constante expansão na indústria alimentícia, devido ao aumento das exigências pelos consumidores por alimentos mais saudáveis. Por isso, há uma busca constante de tecnologias que possibilitem a incorporação de tais substâncias em alimentos. O &#946;-caroteno é uma substância hidrofóbica, cujos benefícios estão relacionados principalmente à sua ação antioxidante. Devido à sua característica hidrofóbica, a utilização deste pigmento implica em desafios tecnológicos para ser incorporado em formulações alimentícias de base aquosa. Por este motivo, a encapsulação em lipossomas pode ser uma ótima alternativa, devido à capacidade de englobar tais substâncias em sua bicamada lipídica. Além da proteção, essas matrizes encapsulantes podem proporcionar a liberação controlada dos ingredientes encapsulados, bem como aumento de sua biodisponibilidade. O objetivo deste trabalho foi produzir e caracterizar dispersões de lipossomas encapsulando &#946;-caroteno estabilizadas com a adição de hidrocolóides(goma xantana ou mistura de goma xantana e goma guar). O diâmetro médio hidrodinâmico, a distribuição de tamanho das partículas e a morfologia foram avaliadas. Os lipossomas produzidos foram vesículas multilamelares (MLV), as distribuições de tamanho dos lipossomas apresentaram-se heterogêneas e as micrografias revelaram a forma esférica dos lipossomas dispersos no meio aquoso, assim como a integridade da sua bicamada lipídica. Foram realizadas análises de quantificação do &#946;-caroteno e colorimetria instrumental, sendo que todas as dispersões mostraram-se eficientes na preservação do &#946;-caroteno ao longo do período de armazenamento. Os hidrocolóides adicionados foram eficazes no aumento da viscosidade da fase contínua, evitando a agregação das vesículas ao longo do tempo, exceto para dispersão estabilizada com a mistura de goma xantana e goma guar, com 0,15% de goma total. Em relação à adição das dispersões de lipossomas em iogurte, as formulações mostraram-se homogêneas, com ausência de grumos ou qualquer tipo de separação de fases, e também foram aprovados por uma parcela de painelistas na análise sensorial. / The use of natural bioactives as ingredients is in constant expansion in the food industry, due to increasing consumer demands for healthier foods. Therefore, there is a constant search for technologies capable of incorporating such substances in food. &#946;-carotene is a hydrophobic substance, whose benefits are mainly related to its antioxidant action. Because of its hydrophobic characteristics, the use of this pigment implies technical challenges to be incorporated into aqueous-based food formulations. For this reason, encapsulation in liposomes may be a good alternative, because of their ability to incorporate such substances in their lipid bilayer. Besides the protection, these encapsulants matrix can provide controlled release of the encapsulated ingredients, as well as increasing its bioavailability. The objective of this study was to produce and characterize dispersions of liposomes encapsulating &#946;-carotene, which were stabilized with the addition of hydrocolloids: xanthan gum or a mixture of xanthan gum and guar gum. The mean hydrodynamic diameter, distribution of particle size and its morphology were studied. The obtained dispersions were multilamellar vesicles (MLV), the liposomes size distributions were heterogeneous and the micrographs revealed the liposomes spherical shape dispersed in aqueous medium, as well as the integrity of their lipid bilayer. The quantification of &#946;-carotene and instrumental colorimetry analyses indicated the liposomes were efficient in the preservation of &#946;-carotene during the storage period. The hydrocolloids added in the dispersions were highly efficient to increase the viscosity of the continuous phase. Therefore, the hydrocolloids were responsible for the prevention of aggregation of the vesicles during the storage period, except for stabilized dispersion with the mixture of xanthan gum and guar gum, with 0.15% gum total. Regarding the dispersions of liposomes added in yoghurt, the formulations were homogeneous, with absence of lumps or any phase separation, and also have been approved by a significant number of the panelists.

Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2017-02-16T15:54:37Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) INFLUÊNCIA DA RADIAÇÃO GAMA NA COMPOSIÇÃO QUÍMICA DO TOMATE (Solanum Lycopersicum).pdf: 1401969 bytes, checksum: feb3a80a7b1738da16023772afc5c60f (MD5) / Made available in DSpace on 2017-02-16T15:54:37Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) INFLUÊNCIA DA RADIAÇÃO GAMA NA COMPOSIÇÃO QUÍMICA DO TOMATE (Solanum Lycopersicum).pdf: 1401969 bytes, checksum: feb3a80a7b1738da16023772afc5c60f (MD5) Previous issue date: 2016-07-29 / A técnica de conservação de alimentos por meio da radiação gama tem-se mostrado eficiente para o aumento do tempo de prateleira de diversos alimentos de origem vegetal. Dentre os vegetais com grandes índices de perda pós–colheita encontrasse o tomate (Lycopersicumesculentum), sendo este a segunda cultura agrícola, de maior difusão no mundo para consumo in natura ou processado. Este alimento tem sido amplamente estudado, uma vez que contêm diversos antioxidantes, como carotenóides, vitamina C, além de tocoferóis e flavonóides que contribui para diversas funções no organismo. Este trabalho tem por objetivo analisar os efeitos da radiação gama nos teores de licopeno, β-caroteno, vitamina C, pH, acidez titulável, coliformes e Samonellas, em tomates comercializados em feiras livres de Recife–PE. Sendo os tomates divididos em três grupos, um controle (não irradiado) e dois irradiados a uma dose de 0,5 kGy e 1,0 kGy a partir de uma fonte de 60Co, com taxa de dose de 2,629 kGy/h. Dentre as observações constatadas pode-se verificar que a radiação ionizante provocou uma diminuição nos teores de licopeno e β- caroteno. Constatou-se uma redução nos teores de vitamina C para as amostras irradiadas, sendo que a dose de 1,0 kGy apresentou maior redução. A análise estatística comprovou que a radiação gama nos tomates estudados permitiu um aumento no tempo de prateleira, evidenciando ser está uma técnica efetiva para conservação no pós-colheita. / The food storage technique by means of gamma radiation has proved effective in increasing the shelf life of many foods of plant origin. Among the vegetables with large post-harvest loss ratios found tomatoes (Lycopersicumesculentum), which is the second crop, the most widespread in the world for fresh consumption or processed. This food has been widely studied since they contain many antioxidants such as carotenoids, vitamin C, and tocopherol, and flavonoids that contributes to various functions in the body. This work aims to analyze the effects of gamma radiation on lycopene content, β-carotene, vitamin C, pH, titratable acidity, coliforms and Samonellas in tomatoes sold in street markets of Recife-PE. As the tomatoes divided into three groups, a control (non-irradiated) and two irradiated at a dose of 0.5 kGy 1.0 kGy from a 60Co source, dose rate of 2,629 kGy / hr. Among the noted observations it can be seen that ionizing radiation caused a decrease in levels of lycopene and β- carotene. It was observed a reduction in vitamin C content for samples irradiated, and the dose of 1.0 kGy showed a reduction. Statistical analysis has shown that the gamma radiation tomatoes studied led to an increase in shelf life, thus demonstrating that it is an effective technique for conservation in postharvest.

Orientador: Lucimara Gaziola de la Torre / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química / Made available in DSpace on 2018-08-23T18:43:23Z (GMT). No. of bitstreams: 1 Zompero_RafaelHenriquedeFreitas_M.pdf: 2571362 bytes, checksum: c3df7d704fb350757e99b3e400dee050 (MD5) Previous issue date: 2013 / Resumo: Este trabalho teve como objetivo principal o desenvolvimento e otimização de um processo escalonável de produção de lipossomas contendo ?-caroteno, visando sua posterior aplicação em produtos de interesse da indústria alimentícia. Para tanto, os efeitos das variáveis que influenciam o processo foram analisados, proporcionando um maior conhecimento a respeito da fenomenologia envolvida na produção dos nanoagregados e maior controle sobre as respostas produzidas pelo sistema. O ?-caroteno é um antioxidante natural, pró-vitamínico e que pode ser empregado como corante natural em formulações alimentícias. Porém sua elevada hidrofobicidade dificulta a aplicação em alimentos de base aquosa. Dentre as metodologias disponíveis para produção de lipossomas, o método de injeção de etanol apresenta-se como o mais facilmente adaptável as necessidades da indústria, possuindo baixo custo de implantação e operação. Na primeira etapa deste trabalho o método de injeção de etanol foi investigado visando a otimização dos parâmetros operacionais para a produção de nanoagregados tendo como objetivo obter propriedades físico químicas tais como diâmetro médio e polidispersidade de forma. Análises estatísticas dos resultados foram realizadas para determinação dos efeitos de cada variável e modelos foram desenvolvidos para predição do comportamento do sistema em diferentes condições de processo. Em seguida, a incorporação de ?-caroteno nos lipossomas obtidos na melhor condição foi avaliada em razões ?-caroteno/lipídio pré-definidas. Ensaios de incorporação de ?-caroteno aos lipossomas revelaram que proporções molares ?-caroteno/lipídio de até 0,5% mostram-se estáveis e solúveis em meio aquoso, resultado confirmado pelos ensaios de monocamadas de Langmuir realizados. A formulação otimizada foi submetida a testes de estabilidade em condições controladas de stress e, em um segundo momento, incorporada a nanofibras de álcool polivinílico e óxido de polietileno através de processo de electrospinning, conferindo proteção extra ao ?-caroteno internalizado. Estas nanofibras produzidas foram caracterizadas quanto a morfologia, diâmetro, presença de fosfolipídios, homogeneidade da distribuição de ?-caroteno e estabilidade a exposição a luz ultravioleta. Testes de rehidratação destas nanofibras foram conduzidos, verificando através de microscopia eletrônica de transmissão a liberação de lipossomas na fase aquosa. Dessa forma, a partir dos resultados obtidos conclui-se que o método de injeção de etanol foi otimizado, sendo que os efeitos de cada uma das variáveis de processo foram elucidados, contribuindo para o desenvolvimento tecnológico da técnica. Os ensaios de aplicação de condições de stress mostram que existe uma barreira a ser vencida no que diz respeito a estabilidade de lipossomas em formulações alimentícias complexas, principalmente para situações de elevada concentração de sacarose e altos teores de NaCl. Por fim, os testes de incorporação em nanofibras mostraram-se bastante promissores, mostrando a viabilidade e benefícios que podem ser agregados ao sistema através da utilização de técnica de eletrofiação contribuindo no desenvolvimento de novos materiais e produtos a serem utilizados pelo setor industrial alimentício / Abstract: The main goal of the present work was the development and optimization of a scalable process for production of ?-carotene loaded liposomes, aiming its application in the food industry. In that way, the effects of the variables that have influence on the process were analysed, providing greater information about the phenomenology evolving the production of these nano aggregates and improved control over the system responses. ?-carotene is a natural antioxidant, pro-vitaminic, and can be employed as a natural colorant in food formulations. However, its high hydrophobicity makes it difficult to be applied in water based foods. The development of feasible processes that can be implemented in the food industry for ?-carotene encapsulation is a actual research challenge. On the first step of this work the ethanol injection method was investigated aiming process parameters optimization for liposomes production with controlled size and polidispersity. Statistical analyses of the results were performed for variables effects determination and mathematical models development for system behaviour prediction. Then, ?-carotene incorporation on liposomes produced at the optimized condition was evaluated studying different ?-carotene/lipid ratios. ?-carotene incorporation experiments revealed that 0.5% ?-carotene/lipid ratios show to be stable and soluble in aqueous media, result confirmed by Langmuir monolayer experiments. The optimized formulation was submitted to stability tests under controlled stress conditions and, in a second stage, incorporated to polyvinyl alcohol and polyethylene oxide nanofibers using electrospinning technique for extra ?-carotene protection. The produced nanofibers were characterized regarding morphology, diameter, phospholipids presence, ?-carotene homogeneity and stability to UV light exposure. Nanofibers rehydration tests were conducted, verifying using transmission electron microscopy that liposomes were released in the aqueous media. In that way, from the obtained results we can conclude that the ethanol injection method was successfully optimized and the evaluation of the effects of each variable was elucidated, contributing to the technological development of the technique. Experiments regarding application of different stress conditions to liposomes formulations show that there is a barrier that must be overcome related to stability of liposomes to complex food formulations. Finally, incorporation tests on nanofibers showed to be promising, demonstrating the feasibility and benefits that can be aggregated to the system by using electrospinning, contributing to the development of new materials and products to be used by the food processing industries / Mestrado / Engenharia Química / Mestre em Engenharia Química