The focus of this research was to develop a plant-based microcapsule for flax oil by complex coacervation. Complex coacervation involves the electrostatic attraction between two polymers of opposing charges. Specifically, the research aimed to: a) identify the ideal biopolymer and solvent conditions required for complex coacervation involving pea protein isolate (PPI) and gum Arabic (GA); b) understand the functional behaviour of PPI-GA complexes as food and biomaterial ingredients; and c) develop methodologies for encapsulating flax oil within PPI-polysaccharide capsules. Complex coacervation between PPI-GA was found to be optimized at a biopolymer weight mixing ratio of 2:1 in the absence of salt. The functional behaviours of the optimized biopolymer mixture were then investigated as a function of pH (4.30-2.40) within a region dominated by complex coacervation. Emulsion stability was found to be greater for PPI-GA mixture systems relative to PPI alone at pH values between 3.10 and 4.00; emulsions produced under one-step emulsification exhibited higher stability compared to those of two-step emulsification at all pH values. Foam expansion was independent of both biopolymer content and pH, whereas foam stability improved for the mixed system between pH 3.10 and 4.00. The solubility minimum was broadened relative to PPI at more acidic pH values. These findings suggested that the admixture of PPI and GA under complexing conditions could represent a new food and/or biomaterial ingredient, and has potential as an encapsulating agent. Two encapsulation processes were employed in this research: high speed mixing (two-step emulsification) and low speed mixing (one-step emulsification). Flax oil capsules formed using the gelatin-GA mixture (as control) under high speed mixing exhibited low moisture content, water activity and surface oil, and afforded adequate protection against oxidation relative to free oil over a 25 d storage period. The PPI-GA mixture failed to produce acceptable capsules using either high or low speed mixing. In contrast, PPI-alginate capsules were produced and exhibited similar chemical properties as gelatin-GA capsules, except with lower encapsulated flax oil content (30% vs. 50% w/w). However, oxidative stability may adversely affected by the low speed mixing condition during encapsulation.

The focus of this research was to develop a plant-based microcapsule for flax oil by complex coacervation. Complex coacervation involves the electrostatic attraction between two polymers of opposing charges. Specifically, the research aimed to: a) identify the ideal biopolymer and solvent conditions required for complex coacervation involving pea protein isolate (PPI) and gum Arabic (GA); b) understand the functional behaviour of PPI-GA complexes as food and biomaterial ingredients; and c) develop methodologies for encapsulating flax oil within PPI-polysaccharide capsules. Complex coacervation between PPI-GA was found to be optimized at a biopolymer weight mixing ratio of 2:1 in the absence of salt. The functional behaviours of the optimized biopolymer mixture were then investigated as a function of pH (4.30-2.40) within a region dominated by complex coacervation. Emulsion stability was found to be greater for PPI-GA mixture systems relative to PPI alone at pH values between 3.10 and 4.00; emulsions produced under one-step emulsification exhibited higher stability compared to those of two-step emulsification at all pH values. Foam expansion was independent of both biopolymer content and pH, whereas foam stability improved for the mixed system between pH 3.10 and 4.00. The solubility minimum was broadened relative to PPI at more acidic pH values. These findings suggested that the admixture of PPI and GA under complexing conditions could represent a new food and/or biomaterial ingredient, and has potential as an encapsulating agent. Two encapsulation processes were employed in this research: high speed mixing (two-step emulsification) and low speed mixing (one-step emulsification). Flax oil capsules formed using the gelatin-GA mixture (as control) under high speed mixing exhibited low moisture content, water activity and surface oil, and afforded adequate protection against oxidation relative to free oil over a 25 d storage period. The PPI-GA mixture failed to produce acceptable capsules using either high or low speed mixing. In contrast, PPI-alginate capsules were produced and exhibited similar chemical properties as gelatin-GA capsules, except with lower encapsulated flax oil content (30% vs. 50% w/w). However, oxidative stability may adversely affected by the low speed mixing condition during encapsulation.

Le travail réalisé au cours de cette thèse est le fruit d’une collaboration étroite entre une équipe de l’Université du MAINE et la société ASHLAND qui est spécialisée dans la synthèse de polymères.Le sujet de cette thèse concerne la synthèse d’un polymère biomimétique de la gélatine afin de l’engager dans un procédé de coacervation complexe permettant l’encapsulation de principes actif ou de colorants.La micro-encapsulation est une méthode permettant d’envelopper de petites particules individuelles ou de gouttelettes dans une couche protectrice de polymères. Largement utilisée en pharmacie, agroalimentaire, cosmétique, les biotechnologies, le phénomène d’encapsulation nécessite la protection des matières et de contrôler la libération de l’actif.Parmi les nombreux procédés d’encapsulation existant, nous nous sommes particulièrement orientés vers une méthodologie de coacervation complexe.Cette dernière est basée sur la complexation entre deux polyélectrolytes de charges opposées. Ainsi, cette technique requiert un polymère anionique et un polymère cationique qui interagissent ensemble (interactions électrostatiques, liaisons hydrogène…) pour former des coacervats.Un des systèmes les plus utilisés de la coacervation complexe est le système gomme d’acacia avec la gélatine en raison de leur abondance et de leur biodégradabilité. Cependant, à cause de son origine animale, l’objectif du travail a consisté à remplacer la gélatine dans le processus d’encapsulation. Pour ce faire, nous avons synthétisé plusieurs polymères spécifiques à partir de différents monomères méthacryliques / méthacrylamides permettant la coacervation et ensuite la réticulation des coacervats formées. Dans un premier temps, nous avons créé une approche permettant de déterminer les conditions optimales de formation des coacervats (le pH d’encapsulation, le ratio de polymère, la force ionique) par potentiel zêta, mesure de la turbidité et par spectroscopie infra-rouge. Par la suite, des essais d’encapsulation avec plusieurs polymères anioniques ont permis de confirmer que la méthodologie établie précédemment était adéquate. Ensuite, un test de réticulation a été réalisé à l’aide d’agents de réticulation afin de rigidifier les parois des coacervats. Enfin, des analyses de force de rupture et de stabilité dans des détergents standards ont été réalisées afin de valider l’application de ces capsules en cosmétique. / The work realized during the last three years CIFRE PhD program consist in a collaborative research between a polymer team of the University of LE MANS and ASHLAND company which the first goal is the synthesis of polymers.The aim of this thesis is the synthesis of biomimetic polymers of the gelatin which were further engaged in the process of encapsulation by complex coacervation.Micro-encapsulation is an effective method of wrapping small individual particles or droplets in polymers protective coating widely used in the fields of food, pharmaceutics, cosmetics, pesticides, biotechnologies. The encapsulation phenomenon target is to protect functional materials and control its release. Among many existing processes, we particularly focused our attention on complex coacervation to produce microcapsules. Complex coacervation is a methodology based on the complexation between two oppositely charged polymers as polyelectrolyte. Thus, this technique requires one anionic and one cationic polymer which are capable to interact together (through electrostatic attractions, hydrogen bond) to form coacervats. One of the most used systems for complex coacervation is the gelatin / acacia gum system. These two natural polymers are widely used as wall material for the capsules due to their abundance and biodegradability. However, gelatin polymer needs to be replaced in the encapsulation process due to its animal origin. In order to substitute gelatin by synthetic polymers in the complex coacervation process, we synthesized several polymers from various monomers authorizing coacervation and further crosslinking. Firstly, we stetted up an approach allowing the evaluation of the optimal conditions of coacervation (pH, ratio, ionic strength) by zetâ potential, and infra-red analysis.Furthermore, encapsulation tests with several anionic polymers were performed which tended to confirm that the methodology was appropriate. Moreover, a test of crosslinking was successfully realized using crosslinkers in order to rigidify coacervats walls. Finally, break strength analysis and the stability in surfactants were conducted to validate the process for cosmetic applications.

A microencapsulação tem sido utilizada promissoramente para melhorar a viabilidade de probióticos. Porém, pouco se sabe sobre o impacto desta na manutenção da funcionalidade do probiótico in vivo. Este trabalho teve como objetivo avaliar duas cepas de lactobacilos, encapsular essas cepas por um sistema envolvendo partículas lipídicas recobertas por interação eletrostática de polímeros e avaliar o efeito da encapsulação na manutenção da capacidade imunomoduladora das cepas. Na primeira etapa do estudo L. rhamnosus 64 e L. paracasei BGP1 foram avaliados quanto à resistência à lisozima e aos fluidos gastrointestinais simulados, perfil de hidrofobicidade da parede celular, susceptibilidade a antibióticos, atividade antagonista contra patógenos e capacidade de utilização de prebióticos. Em etapa seguinte as cepas foram encapsuladas e as microcápsulas avaliadas quanto à morfologia, tamanho e distribuição de partículas, umidade, atividade de água e efeito do pH e temperatura em sua estabilidade. Para avaliar a susceptibilidade dos microrganismos ao processo de encapsulação e estresse tecnológico, investigou-se o impacto do efeito da homogeneização com Ultra-Turrax, tolerância à temperatura, salinidade, diferentes pH e fluidos gastrointestinais simulados na viabilidade das bactérias. A viabilidade dos microrganismos durante a estocagem também foi estudada. Por fim, avaliou-se a manutenção da capacidade imunomoduladora dos microrganismos microencapsulados por meio da dosagem de citocinas pró e anti-inflamatórias e determinação da capacidade protetora contra infecção de Salmonella entérica sorovar Typhimurium em modelo animal. Os microrganismos demonstraram resistência à lisozima, com taxas de sobrevivência superiores a 80%. O perfil de hidrofobicidade da parede celular, foi baixo, entre 8,47 e 19,19%. Demonstraram resistência apenas à vancomicina (35 µg) e eritromicina (15 µg). As duas cepas foram capazes de antagonizar o crescimento de Escherichia coli V517, Salmonella enteritidis OMS-Ca, Staphylococcus aureus 76 e Listeria monocytogenes ATCC 15313. Quanto à capacidade de utilização de prebióticos, os microrganismos apresentaram comportamentos inversos, utilizaram preferencialmente inulina, raftilose 95 e lactulose. Nos testes de resistência aos fluidos gastrointestinais simulados constatou-se declínio significativo de células viáveis, com subtração de até 3,37 log UFC/mL. As cápsulas obtidas apresentaram formato típico e tamanhos médios de 80,12 ± 1,89 e 83,92 ± 1,70 µm. Condições de pH extremos (1,5 e 9,0) e temperatura superior a 50 °C comprometeram a estabilidade das cápsulas. A encapsulação melhorou significativamente a tolerância dos microrganismos à altas concentrações de sal e elevação de temperatura. Além disso, favoreceu a resistência dos microrganismos frente aos fluidos gastrointestinais simulados. A estabilidade dos microrganismos durante o período de estocagem também foi favorecida, após 120 dias de estocagem a 7 e 25 °C a concentração de microrganismos viáveis permaneceu superior a 7,0 log UFC/g. Nos testes in vivo para avaliação da manutenção da capacidade de imunomodulação constatou-se através de dosagem de citocinas (IL-2, IL-6, IL-10 e TNF-α) e IgA secretora, que a encapsulação não alterou a resposta imunológica provocada pelas cepas estudas. Concluiu-se que os microrganismos apresentaram comportamento in vitro de acordo com o desejado para candidatos ao uso de probióticos. A microencapsulação foi bem-sucedida, proporcionando as duas cepas maior resistência frente às condições adversas e de estresse tecnológico. / Microencapsulation has been used successfully to improve the viability of probiotics microorganisms. The aim of this work was to evaluate two strains of lactobacilli, to encapsulate these strains by a system involving lipid particles coated by electrostatic interaction of polymers and to evaluate the effect of encapsulation in the maintenance of immunomodulatory capacity of these strains. In the first stage of the study L. rhamnosus 64 and L. paracasei BGP1 were evaluated for resistance to lysozyme and simulated gastrointestinal fluids, cell wall hydrophobicity profile, susceptibility to antibiotics, antagonist activity against pathogens and prebiotic utilization capacity. In the next step, the strains were encapsulated and the microcapsules evaluated regarding morphology, particle size and distribution, moisture, water activity and pH and temperature. The tolerance to temperature, salinity, different pH and simulated gastrointestinal fluids in the viability of the bacteria were also evaluated. The probiotics viability during the storage period was also studied. Finally, the maintenance of the immunomodulatory capacity of the encapsulated microorganisms was evaluated by means of the dosage of pro and anti-inflammatory cytokines and IgA. L. rhamnosus 64 and L. paracasei BGP1 demonstrated resistance to lysozyme, with survival rates above 80%. The hydrophobicity profiles of the cell wall were from 8.47 to 19.19%. Susceptibility to antibiotics also corroborated the literature, demonstrating resistance only to vancomycin (35 µg) and erythromycin (15 µg). The two strains were able to antagonize the growth of Escherichia coli V517, Salmonella enteritidis OMS-Ca, Staphylococcus aureus 76 and Listeria monocytogenes ATCC 15313. As far as the capacity of using prebiotics the two strains of lactobacilli presented inverse behaviors, they used preferably inulin, raftilose 95 and lactulose. In the tests of resistance to the simulated gastrointestinal fluids it was verified a significant decline of viable cells, with subtraction of up to 3.37 log CFU / mL, justifying the application of encapsulation technology. In the encapsulation step the capsules were produced with gum arabic, porcine gelatin and vegetable fat. The obtained capsules presented a typical format and average sizes of 80.12 ± 1.89 and 83.92 ± 1.70 µm. Extreme pH conditions (1.5 and 9.0) and temperature above 50 ° C compromised the stability of the capsules. The encapsulation significantly improved the tolerance of microorganisms to high salt concentrations and elevation of temperature. In addition, it favored the resistance of the microorganisms to the simulated gastrointestinal fluids. The stability of the microorganisms during the storage period was also favored, after 120 days of storage at 7 and 25 ° C the concentration of viable microorganisms remained higher than 7.0 log CFU / g. In the in vivo tests for evaluation of the maintenance of the immunomodulation capacity, the cytokines (IL-2, IL-6, IL-10 and TNF-α) and secretory IgA were determined, that encapsulation did not alter the immunological response by the strains of lactobacilli studied. It was concluded that the microorganisms presented in vitro behavior in accordance with the one desired for probiotic candidates. Microencapsulation was successful, giving both strains greater resistance to adverse conditions and technological stress.

Orientador: Lireny Aparecida Guaraldo Gonçalves / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-16T15:19:46Z (GMT). No. of bitstreams: 1 Mascarenhas_Maria_Cristina_Chiarinelli_Nucci_M.pdf: 34073658 bytes, checksum: 2317d29ea00a70488b5f569fb05c6ce5 (MD5) Previous issue date: 2010 / Mestrado / Mestre em Tecnologia de Alimentos

Orientador: Carlos Raimundo Ferreira Grosso / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-05T13:49:57Z (GMT). No. of bitstreams: 1 Alvim_IzabelaDutra_D.pdf: 8886794 bytes, checksum: 16da2e8dd31802c6ce217aae14d9e70f (MD5) Previous issue date: 2005 / Resumo: A microencapsulação é uma técnica para recobrimento de substâncias para a proteção e/ou liberação controlada das mesmas. As microcápsulas podem ser uma alternativa para obtenção de uma dieta para alimentação das larvas de peixe na piscicultura intensiva. Dois métodos de microencapsulação foram empregados para produção de micropartículas, potenciais na substituição do alimento vivo (rotíferos e artêmias) oferecido às larvas de peixe nos primeiros estágios de desenvolvimento. O primeiro baseou-se na secagem em spray dryer de uma dieta líquida. Essa dieta desidratada sofreu aglomeração e recobrimento para manipulação do diâmetro médio das partículas e solubilidade. Os diâmetros médios dos aglomerados foram significativamente maiores que da dieta desidratada sem aglomeração. As solubilidades em sólidos solúveis e em proteínas solúveis da dieta sem recobrimento foram altas para 120 minutos de permanência em água. A adição de óleo à dieta desidratada e o recobrimento polimérico reduziu esses valores de solubilidade. O aspecto apresentado pela dieta desidratada sem recobrimento foi característico de produtos desidratados por spray dryer. Os aglomerados apresentaram camada de recobrimento com falhas, o que justificou as baixas diminuições de solubilidades observadas. O segundo processo de microencapsulação foi a coacervação complexa entre gelatina e goma arábica, e como recheios foram utilizados uma mistura de oleoresina de páprica e óleo de soja e dois compostos hidrofílicos (glicose ou isolado protéico de soro de leite) retidos em matrizes lipídicas sólidas. Por microscopias diversas (confocal, ótica e eletrônica de varredura) as micropartículas coacervadas se apresentaram esféricas e multinucleadas. As micropartículas coacervadas contendo oleoresina de páprica e óleo de soja foram reticuladas com glutaraldeído ou com transglutaminase, e submetidas à secagem por estufa com circulação de ar, liofilizador e spray dryer. A secagem em estufa não permitiu a obtenção de um material com micropartículas individualizadas enquanto a liofilização permitiu a manutenção da estrutura esférica para todas as amostras inclusive a sem reticulação. A secagem em spray dryer apresentou baixíssimo rendimento, e só foi possível para micropartículas reticuladas, com integridade das estruturas associada ao tipo/concentração de reticulante. A liberação da oleoresina foi avaliada em etanol absoluto por 120 minutos, para as micropartículas coacervadas úmidas com e sem reticulação e suas respectivas amostras desidratadas. A liberação do recheio foi alta (acima de 95%) para todas as amostras úmidas, exceto para a amostra reticulada com 1,0mM/g.ptn de glutaraldeído. As amostras desidratadas por liofilização tiveram liberação de seu conteúdo reduzida, não ultrapassando 35,4% após 120 minutos para todos os tratamentos. A liberação do recheio das micropartículas desidratadas por spray dryer foi baixa e proporcional a manutenção da integridade das partículas. Para veiculação dos compostos hidrofílicos nos coacervados, foram produzidas micropartículas lipídicas (spray chilling). Essas micropartículas lipídicas foram incorporadas com sucesso nos coacervados. A liberação dos compostos solúveis do interior dos coacervados foi maior para glicose que para a proteína, para 20 horas de permanência em água. A aceitação das micropartículas produzidas foi avaliada em um ensaio biológico in vivo com larvas de pacu. Foram testadas uma dieta aglomerada e quatro coacervados produzidos utilizando gelatina bovina ou gelatina de peixe na parede e óleo de soja ou gordura de peixe como recheio. O nível de aceitação das dietas foi de maiores valores para os coacervados produzidos com gelatina bovina/gordura de peixe e gelatina bovina/óleo de soja, seguidos pelo coacervado produzido com gelatina de peixe/óleo de soja, pelo aglomerado e por último o coacervado produzido com gelatina de peixe/gordura de peixe. Os coacervados produzidos com gelatina bovina contendo óleo de soja ou gordura de peixe apresentaram-se promissores como dietas necessitando ainda de ajustes nutricionais para atenderem as exigências das larvas em crescimento / Abstract: The microencapsulation is one technique for covering or evolving substances with the aim to provide protection and/or controlled release of the same ones. The microcapsules can be an alternative for attainment of a diet for feeding of the larvae of fish in the intensive aquaculture. Two methods of microencapsulation had been used for production of microparticles in the substitution of the alive food (rotifers and artemias) offered to the larvae of fish in the first periods of growing. The first one was based on the spray drying of one nutritionally and balanced liquid formulation. The dehydrated diet was agglomerated adjust the average size and solubility of the particles. The size of the agglomerated particles was increased efficiently. The solubilities in total soluble solids and soluble proteins of the diet without covering had been high with values (above 50%) for 120 minutes of permanence in water. The addition of oil to the dehydrated diet (OD) and the agglomation with pectate and calcium reduced the values of solubility. The aspect presented for the diet dehydrated without covering was characteristic of products dehydrated by spray dryer. The surface of the agglomerated particles presented some imperfections, which justified the low reductions of solubilities. The second process used was the complex coacervation between gelatin and acacia gum and as a core materials, a mixture of paprika oleoresin and vegetable soy oil and two hydrophilic composites (glucose or whey protein isolate). After, the lipidic microparticles were used as core material for microparticles obtained using complex coacervation. Using different types of microscopies (confocal, optical and scanning electronic microscopy) it was possible to characterize the coacervated microparticles that showed spherical geometry and multinuclear distribution of the core material. The microparticles containing paprika oleoresin of paprika and vegetable soy oil as core material had been crosslinked with glutaraldehyde or transglutaminase, and were dried using one oven with air circulation, spray dryer and freeze drying processes. The drying using oven did not allowed the attainment of a dry material presenting free flowing. The freeze drying, on the other side, allowed the attainment of microparticulated material showing spherical structure and free flowing for all samples including samples without cross-linking. The yield of the spray drying process was very low. This process did not work when non crosslinked samples were dried. The high level of cross-linking using 1.0mM/g of ptn showed the best results compared with transglutaminase or glutaraldehyde at 0.1mM/g of protein (reaction time of 18 hour for both) showing the maintenance of the moist microparticles structure. The release of the oleoresin was evaluated for the moist and dehydrated samples with and without crosslinking using ethanol as the release medium during 120 minutes. The core release observed was above 95% for moist coacervated without crosslinking, crosslinked using transglutaminase and for samples crosslinked with the low level of glutaraldehyde. The release level decreased when concentration of glutaraldehyde was increased. Dryed samples using freeze drying showed a great decrease on the release amount, not exceeding 35.4% after 120 minutes for all the treatments. The release of the core from the dehydrated microparticles using spray dryer was proportional to the maintenance of the integrity of particles. Again, cross-linking using high concentration of glutaraldehyde/g.ptn produced the best results.Lipídic microparticles had been incorporated successfully in the coacervated microparticles. The amount of released soluble composites using water solution was high to glucose and relative low for the protein after 20 hours of experiment. The acceptance of the microparticles was evaluated in a live biological assay using larvae of pacu. A diet agglomerated with calcium pectate and four coacervated microparticles using bovine gelatin or fish gelatin as the wall materials and vegetable soy oil or fat fish as core materials had been tested. Ranking of acceptance of the diets showed bigger values for the coacervated microparticles produced with gelatin/fat fish or gelatin/soy oil, followed by the microparticles produced with fish gelatin/soy oil, agglomerated particles and finally coacervate particles using fish gelatin/fat fish. The coacervation process showed interesting results but improvement on the nutritional balance needs to be done / Doutorado / Nutrição Experimental e Aplicada à Tecnologia de Alimentos / Doutor em Alimentos e Nutrição

Orientador: Carlos Raimundo Ferreira Grosso / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-12T17:22:27Z (GMT). No. of bitstreams: 1 Celis_FernandoTello_M.pdf: 11548005 bytes, checksum: 269edd777d012837321ae7b167499c40 (MD5) Previous issue date: 2009 / Resumo: Micropartículas foram produzidas por coacervação complexa utilizando gelatina e goma arábica como materiais formadores de parede e uma mistura de oleoresina de páprica-óleo de soja (1:10) em quantidade que corresponde a 50% de massa dos materiais de parede. A ordem de produção das emulsões, gelatina/oleoresina de páprica-óleo de soja ou goma arábica/oleoresina de páprica-óleo de soja, a reticulação das micropartículas com transglutaminase (10 a 50U/g.ptn) ou com glutaraldeído (1mM/g.ptn) e a melhora de características funcionais em função desses fatores foram avaliadas. Foram avaliadas a capacidade de inchamento, resistência à solução de dodecil sulfato de sódio (SDS, 2 e 5%), à temperatura (65 e 97°C/15 min), valores de pH 1, 2 e 7 e resistência a condições simuladas do pH do estômago e intestino (temperatura e enzimas). Adicionalmente foi acompanhado o efeito dos tratamentos na liberação do recheio hidrofóbico em óleo de girassol. Microscopia ótica, eletrônica de varredura e espectrofotometria foram utilizadas para as avaliações de resistência e de liberação. As micropartículas apresentaram forma esférica e tamanho médio na faixa de 55-70mm, com o recheio distribuído de forma multinuclear e homogênea. As micropartículas resistiram, mantendo-se íntegras, nas temperaturas testadas, às soluções de SDS, às condições drásticas de pH ácido simulando o suco gástrico (pH, pepsina e temperatura) especialmente aquelas tratadas com transglutaminase a partir de 20U/g.ptn enquanto as não reticuladas se desfizeram. Todas as micropartículas produzidas se desfizeram nas condições simuladas do intestino (pH, pancreatina e temperatura). A liberação de oleoresina de páprica-óleo de soja em óleo de girassol foi inversamente proporcional a quantidade de agente reticulante utilizado. O aumento do reticulante diminuiu a quantidade liberada do composto de cor. Melhores resultados de liberação foram obtidos para micropartículas produzidas com a emulsão goma arábica/oleoresina de páprica-óleo de soja. As avaliações da liberação da oleoresina de páprica-óleo de soja após submeter às micropartículas às condições entéricas ácido-enzima mostraram que micropartículas sem reticulação liberaram em torno de 55% da oleoresina de páprica-óleo de soja encapsulada enquanto para micropartículas reticuladas com transglutaminase a 50U/g.ptn liberaram em torno de 33% da oleoresina de páprica-óleo de soja encapsulada. Melhor retenção foi observada para micropartículas reticuladas com glutaraldeído que liberaram em torno de 11% da oleoresina de páprica-óleo de soja encapsulada. No teste gástrico a ordem de preparação da emulsão não apresentou diferenças na quantidade liberada após a incubação em meio fortemente ácido contendo pepsina / Abstract: Microparticles were produced by complex coacervation using gelatin and gum Arabic as wall forming materials and a mixture of paprika oleoresin-soy oil (1:10) in a quantity that correspond to 50% of wall material mass. The emulsions production order, gelatin/ paprika oleoresin-soy oil or gum Arabic/paprika oleoresin:soy oil, the crosslinking of the microparticles with transglutaminase (10 to 50 U/g.ptn) or with glutaraldehyde (1mM/g.ptn) and the improvement of functional characteristics as a function of these factors were evaluated. Swelling capacity, resistance to sodium dodecyl sulfate solution (SDS, 2 and 5%), to temperature (65 and 97°C/15 min), to pH values 1, 2 and 7 and the r esistance to simulated stomach and intestine pH (temperature and enzymes) were evaluated. Additionally, the effect of treatments on the release of hydrophobic core in sunflower oil was measured. Optic and scanning electronic microscopy and spectrophotometry were used to the resistance and release evaluations. The microparticles showed spherical shape and mean diameter from 55 to 70 mm, with the core distribution multinuclear and homogeneous. The microparticles remained intact in the temperatures tested, in SDS solutions, in drastic conditions of acid pH simulating the gastric juice (pH, pepsin, and temperature) specially the ones treated with transglutaminase concentration at least 20 U/g.ptn while the ones not crosslinked were broken. All the microparticles were solubilized in the simulated intestine conditions (pH, pancreatin, and temperature). The release of paprika oleoresin-soy oil in sunflower oil was inversely proportional to crosslinking agent quantity used. The increasing of crosslinking agent decreased the release of color compound quantity. The best results of release were obtained for microparticles produced with an emulsion gum Arabic/paprika oleoresin-soy oil. In acid-enzyme enteric conditions, the microparticles without crosslinking released around 55% of encapsulated paprika oleoresin-soy oil while crosslinked microparticles with transglutaminase at 50U/g.ptn released around 33% of initially encapsulated paprika oleoresin-soy oil. The best retention was observed for microparticles crosslinked with glutaraldehyde that released around 11% of encapsulated paprika oleoresin-soy oil. In the gastric test, the emulsion preparation order not showed differences in the released quantity after incubation in the strong acid environment containing pepsin / Mestrado / Consumo e Qualidade de Alimentos / Mestre em Alimentos e Nutrição

Orientadores: Carlos Raimundo Ferreira Grosso, Carmen Silvia Favaro Trindade / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-12T17:20:57Z (GMT). No. of bitstreams: 1 Rocha_GlauciaAguiar_M.pdf: 2611402 bytes, checksum: 8ceadf584c80cdf50874a2ee378e5e9b (MD5) Previous issue date: 2009 / Resumo: O interesse no licopeno cresceu em anos recentes, devido aos estudos que o associam à diminuição do risco de desenvolvimento de doenças cardiovasculares e câncer. Porém, devido ao seu alto grau de insaturação, este carotenóide é propenso à isomerização e oxidação durante o processamento e a estocagem, dificultando sua utilização na indústria de alimentos. A microencapsulação pode amenizar essa situação, aumentando sua estabilidade e tornando possível sua incorporação em sistemas alimentícios sem a perda de suas propriedades funcionais. Assim, o objetivo deste trabalho foi microencapsular licopeno pelos métodos de coacervação complexa e spray drying, utilizando gelatina e goma arábica como agentes encapsulantes para o primeiro método, seguido de secagem do material coacervado por liofilização e amido modificado (Capsul®) para o segundo método. As variáveis na obtenção das micropartículas foram a concentração de polímeros de parede (somente na coacervação) e a quantidade de recheio. As micropartículas obtidas foram avaliadas morfologicamente por microscopia ótica (somente coacervadas) e quanto à eficiência de encapsulação. Foram submetidas a um teste de estabilidade em comparação ao material de recheio na forma livre e foram também caracterizadas quanto à densidade, higroscopicidade e morfologia (ótica e eletrônica de varredura). Foi realizada a incorporação das micropartículas e do material livre em uma formulação de bolo, que foi utilizada como sistema modelo, a qual foi avaliada quanto à cor. Os valores de eficiência de encapsulação foram superiores a 90% para as micropartículas coacervadas e entre 20 e 30% para as obtidas por spray drying. Através do teste de estabilidade foi possível verificar que os dois métodos de microencapsulação ofereceram maior proteção ao licopeno em relação à sua forma livre. A aplicação em bolo das micropartículas coacervadas não liofilizadas e das obtidas por spray drying foi satisfatória, enquanto que para a aplicação das micropartículas coacervadas liofilizadas houve baixa transferência de cor / Abstract: The interest in lycopene increased in recent years due the studies that associate it with the reduction of the risk of cardiovascular diseases and cancer development. However, due the high degree of insaturation, this carotenoid is propense to isomeration and oxidation during the processing and storage, being difficult its use in food industry. The microencapsulation can improve this situation, increasing its stability and rendering possible its addition in food systems without losses of its functional properties. Thus, the aim of this work was to microncapsulate lycopene by complex coacervation and spray drying methods, using gelatin and arabic gum as wall materials to the first method, followed by the drying of the coacervated material by liofilization, and modified starch (Capsul®) for the second method. The differences in the process to obtain the microcapsule were the polymers concentration (only for coacervation) and amount of lycopene. The microcapsules obtained were morphologically evaluated by optic microscopy (only coacervates) and about the encapsulation efficiency. They were submitted to a stability test in comparison with the free material and also were characterized about density, hygroscopicity and morphology (optical and scanning electron). The addition of capsules and free lycopene in a cake formulation was carried out and they were evaluated about the intensity of the color. The values of encapsulation efficiency were higher than 90% to coacervates capsules and between 20 and 30% to those obtained by spray drying. The study of stability showed that microencapsulation offered higher protection to lycopene than its in free way. The addition of coacervates (no freeze dried) and spray dryed microcapsules in cake was satisfactory, whereas for the application of freeze dried coacervates particles, the color transference was low / Mestrado / Consumo e Qualidade de Alimentos / Mestre em Alimentos e Nutrição

Orientador: Carlos Raimundo Ferreira Grosso / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-23T08:09:57Z (GMT). No. of bitstreams: 1 Braga_AndreaHelenaFerreira_D.pdf: 2190091 bytes, checksum: 46376779b7866dd62ac05c2a6abc7be6 (MD5) Previous issue date: 2013 / Resumo: A eficiente combinação entre proteínas e polissacarídeos produz filmes biodegradáveis com melhores propriedades funcionais, a interação associativa entre os grupamento presentes na cadeia polimérica dos biopolímeros gera uma rede polimérica mais coesa e resistente. Esta associação, em geral, ocorre através das interações eletrostáticas entre os biopolímeros que é controlada pelas condições de pH, força iônica e proporção estequiométrica dos polimeros, entre outros parâmetros. O objetivo deste trabalho foi utilizar o método de coacervação na elaboração de filmes a base de gelatina-quitosana (GEL/QUI), gelatina-pectina (GEL/PEC) e de gelatina-goma arábica (GEL/GAR) com o intuito de promover maiores interações intermoleculares entre os biopolímeros, formando filmes mais resistentes mecanicamente e menos susceptíveis a ação da água. O desenvolvimento deste trabalho pode ser dividido em: 1-) Análise da solução filmogênica de GEL/QUI ou PEC ou GAR (em várias proporções estequiométricas): nesta etapa foi feito um estudo para definir o pH de coacervação para cada formulação utilizando o ?-potencial zeta. No pH de coacervação ocorre a máxima interação eletrostática entre os biopolímeros gerando carga elétrica neutra para a solução filmogênica (?-potencial zeta igual a zero), devido a neutralização da carga elétrica positiva (-NH4+) com a carga elétrica negativa (-COO-) dos biopolímeros. 2-) Elaboração dos filmes coacervados foi realizada em várias proporções estequiométricas no seu devido pH de coacervação. 3-) Caracterização dos filmes de acordo com o aspecto visual, propriedades mecânicas, permeabilidade ao vapor de água (PVA), solubilidade em água (SOL), umidade (UMI) e opacidade (Op). Análises complementares de difração de raio-X (DRX), espectroscopia de infravermelho (FTIR), microscopia eletrônica de varredura (MEV) e calorimetria diferencial de varredura (DSC) foram realizadas em alguns filmes. 4-) Seleção dos filmes: foi escolhida a proporção estequiométrica que produziu filmes com maior resistência mecânica, menor PVA e SOL. 5-) Concentração do material polimérico: na formulação selecionada foram testadas maiores concentrações de material polimérico (4, 6, 8 e 10%) com o intuito de reduzir o tempo de secagem dos filmes coacervados. Estes filmes foram novamente caracterizados (propriedades mecânicas, PVA, SOL e UMI). A concentração de material polimérica escolhida para prosseguir o estudo associou o menor tempo de secagem sem alterar a PVA e SOL dos filmes. 6-) Adição do plastificante: nesta etapa foi avaliado o tipo de plastificante (triacetina e glicerol) e a sua concentração (2,5, 5, 7,5, 10, 15, 20, 25 e 30g de plastificante/100g de material polimérico). Os filmes coacervados de GEL/QUI foram elaborados em pH alcalino (pH de coacervação entre 6,2-7,2) por combinar um polissacarídeo catiônico (QUI) com a GEL. Formulações com maior teor de GEL (10:1 e 20:1 de GEL/QUI) confere ao filme coacervado maior resistência à ruptura, flexibilidade e menor PVA. As análises de difração de raio-X e de FTIR evidenciam a presença de interações eletrostáticas atrativas entre as cadeias da gelatina e a quitosana. Ao comparar os filmes coacervados com os filmes compostos (sem ajuste de pH) verificou-se que o método de coacervação conferiu ao filme maior tensão na ruptura, menor PVA e menor SOL. Ao aumentar a concentração de material polimérico de 2% para 6% constatou-se redução pela metade do tempo de secagem, além de promover maior resistência a ruptura e menor PVA. Os filmes coacervados de GEL/PEC e GEL/GAR foram elaborados em pH ácido (pHcoacervação igual a 4,0 e 4,5-5,0, respectivamente), isto ocorre devido a interação do grupo carboxil (-COO-) dos polissacarídeos aniônicos com o grupo amina (-NH4+) da GEL, já que a proteína encontra-se carregada positivamente somente em pHs abaixo do seu ponto isoelétrico - pI (pI da GEL 4,8-5,2). Para filme coacervado de GEL/PEC, somente a solução filmogênica contendo 20:1 de GEL/PEC apresentou-se homogênea e com em condição de coacervação (pHcoacervação=4,0). O espectro de FTIR do filme coacervado de GEL/PEC (20:1) mostrou que o grupo carboxil da PEC pode estar interagido com o grupo amina da GEL gerando novos grupamentos amida (1630 e 1530 cm-1). A incorporação do glicerol foi mais eficiente na matriz polimérica da GEL/PEC do que a triacetina, isto foi comprovado pela análise visual e pela difração de raio-X. Filmes coacervados de GEL/GAR apresentaram-se coesos, uniformes e homogêneos. Filmes coacervados com alto teor de GEL mostraram-se mais resistentes e flexíveis e menos solúveis em água do que as formulações com menor teor de GEL (1:1 e 2:1 de GEL/GAR), resultados confirmados pelas análises de FTIR, DSC e DRX. O método de coacervação formou filmes mais resistentes mecanicamente e a ação da água do que nos filmes não coacervados (sem ajuste de pH). O aumento da concentração do material polimérico de 2 para 6% reduziu o tempo de secagem do filme de GEL/GAR (10:1) pela metade sem alterar suas propriedades funcionais. Todos os filmes coacervados de GEL/QUI, PEC ou GAR, de modo geral, apresentaram o mesmo comportamento frente a a adição do plastificante. A adição do glicerol foi mais eficiente devido sua melhor incorporação na matriz polimérica produzindo filmes coacervados mais flexíveis, mais resistentes, com menor PVA e mais transparentes do que os filmes coacervados contendo triacetina. Os resultados apresentados neste trabalho confirmam a eficiencia do método de coacervação em melhorar a compatibilidade, e consequentemente, intensificando a interação eletrostáticas entre a proteína e o polissacarídeo. Isto reflete diretamente nas propriedades funcionais dos filmes coacervados, pois a maior interação entre os biopolímeros promove a formação de uma rede polimérica mais densa e coesa, gerando filmes com maior TR, menor PVA, menor ELO e em alguns formulações mais resistentes a ação da água (menor SOL) / Abstract: The efficient combination of proteins and polysaccharides produces biodegradable films with improved functional properties; the associative interaction between the groupings present in the polymer chain of biopolymers generates a more cohesive and resistant polymer network. This association generally occurs through electrostatic interactions between the biopolymers which is controlled by the conditions of pH, ionic strength and stoichiometric ratio of polymers, among other parameters. The aim of this study was to use the coacervation method in developing films based on gelatin-chitosan (GEL/QUI), on gelatin-pectin (GEL/PEC) and on gelatin-gum arabic (GEL/GAR), in order to promote greater intermolecular interactions between biopolymers, forming mechanically stronger films and less susceptible to the action of water. The development of this work can be divided into: 1-) Analysis of the film solution GEL/QUI or PEC or GAR (in various stoichiometric ratios): in this step a study was done to determine the pH of coacervation for each formulation using ?-zeta potential. At pH of coacervation occurs maximum electrostatic interaction between biopolymers generating a neutral electric charge for filmogenic solution (? - zeta potential of zero), due to neutralization of the positive charge (-NH4+) with negative charge (-COO-) of biopolymers. 2-) Development of coacervated films was held in various stoichiometric ratios in its proper pH of coacervation. 3-) Characterization of films according to the visual appearance, mechanical properties, permeability to water vapor (PVA) water solubility (SOL), humidity (UMI) and opacity (Op). Complementary analyzes of X-ray diffraction (XRD), infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and differencial scanning calorimetry (DSC) were performed in some films. 4-) Selection of films: it was chosen a Stoichiometric ratio which produced films with higher mechanical strength and lower PVA SOL. 5-) Concentration of polymeric material: higher concentration of polymeric material (4, 6, 8, and 10% ) were tested in the selected formulation in order to reduce the drying time of the coacervated films. These films were further characterized (mechanical properties, PVA, SOL and UMI). The concentration of polymeric materials chosen for further study associated the lowest drying time without changing the SOL and PVA films. 6-) Addition of plasticizer: In this step the type of plasticizer (triacetin or glycerol) and its concentration was evaluated (2.5, 5, 7.5, 10, 15, 20, 25 and 30g plasticizer/100g polymeric material). The coacervated films GEL/CHI were prepared at alkaline pH (pH of coacervation between 6.2-7.2) by combining a cationic polysaccharide (QUI) with GEL. Formulations with higher content of gel (10:1 and 20:1 GEL/QUI) gave the coacervated film higher tensile strength, flexibility and less PVA. The analysis of X- ray diffraction and FTIR showed the presence of attractive electrostatic interactions between the chains of gelatin and chitosan. Comparing coacervated films with composite films (without pH adjustment) it was found that the coacervation method gave the highest film tensile strength, lower PVA and lower SOL. By increasing the concentration of polymeric material from 2% to 6% a reduction by half of the drying time was found promoting a greater resistance to breakage and lower PVA. The coacervate films GEL/PEC and GEL/GAR were prepared in acidic pH (pH of coacervation equal to 4.0 and 4.5 to 5.0, respectively), this occurs due to interaction carboxyl group (-COO-) of anionic polysaccharides with amino group (-NH4+) of GEL, since the protein is positively charged at pHs only below its isoelectric point - pI (pI of 4.8 to 5.2 GEL). To coacervate film GEL/PEC, only film solution containing 20:1 GEL/PEC appeared homogeneous and in condition coacervation (pH of coacervation = 4.0). The FTIR spectrum of the coacervated film GEL/PEC (20:1) showed that the carboxyl group of the PEC may have been interacted with the amino group generating new clusters of GEL amide (1630 and 1530 cm-1). The incorporation of the glycerol was more efficient in the polymer matrix of GEL/PEC than triacetin. It was confirmed by visual analysis and by X -ray diffraction. Films coacervated GEL/GAR presented themselves cohesive, uniform and homogeneous. Coacervated films with high gel content were more resistant and flexible and less soluble in water than the formulations with lower content of gel (1:1 to 2:1 GEL/GAR), which was confirmed by analysis of FTIR, DSC and XRD. The coacervation method formed films more mechanical and water resistant than in the non coacervated films. (without pH adjustment). Increasing the concentration the polymeric material from 2 to 6 % reduced the drying time of the film GEL/GAR (10:1) by half without altering their functional properties. All coacervated films GEL/QUI, PEC or GAR, in general, showed the same behavior in addition of plasticizer. The addition of glycerol was more efficient because of its better incorporation into the polymer matrix coacervated producing more flexible films, tougher, with less PVA and more transparent than coacervated films containing triacetin. The results presented here confirm the efficiency of the coacervation method to improve the compatibility, thus intensifying the electrostatic interaction between protein and polysaccharide. This highly reflects in the functional property of coacervated films, since the bigger interaction among biopolymers promotes the formation of more dense and united polymeric net, generating films with higher TR, smaller PVA, less ELO in some formulations and more resistant to the action of water (less SOL) / Doutorado / Consumo e Qualidade de Alimentos / Doutora em Alimentos e Nutrição

Le bénéfice de l’encapsulation des molécules bioactives a séduit les industries agroalimentaires depuis plusieurs décennies. Plus récemment des études ont montré la capacité de protéines alimentaires de charge opposée à s’assembler en microsphères par coacervation complexe. La compréhension des forces gouvernant le processus de coacervation entre protéines et l’influence exercée par la présence de bioactifs demeurent des prérequis pour l’utilisation des coacervats complexes comme agent d’encapsulation. Dans ce contexte, l’objectif de mon projet de thèse a été de comprendre le mécanisme de coacervation complexe entre la ¿-lactoglobuline (¿-LG) chargée négativement, et la lactoferrine (LF) chargée positivement, en absence et en présence de petits ligands. La LF a présenté une coacervation préférentielle avec le variant A de la¿¿-LG qui se distingue du variant B par la substitution de 2 acides aminés. Au niveau moléculaire, deux sites de fixation de la ¿-LG sur la LF ont été identifiés.En outre, par la mesure d’une part des coefficients de diffusion rotationnel et d’autre part de la cinétique de diffusion des entités moléculaires constituant les coacervats, il est suggéré que ces derniers sont formés à partir de -LG libre¿¿de pentamère, LF(-LG2)2, ainsi que des entités plus larges, (LF-LG2)n. Afin d’évaluer l’effet de la présence de petits ligands sur la coacervation complexe entre la -LG et la LF, des ligands modèles (ANS et acide folique) ont été utilisés. Dans les conditions expérimentales testées ces deux ligands n’ont pas d’affinité pour la -LG, mais après interact / Encapsulation of bioactives has been used by the food industries for decades and represents a great potential for the development of innovative products. Given their versatile functional properties, milk proteins in particular from whey have been used for encapsulation purposes using several encapsulation techniques. In parallel, recent studies showed the ability of oppositely charged food proteins to co-assemble into microspheres through complex coacervation. Understanding the driving forces governing heteroprotein coacervation process and how it is affected by the presence of ligands (bioactives) is a prerequisite to use heteroprotein coacervates as encapsulation device. In this context, the objective of my thesis work was to understand the mechanism of complex coacervation between -lactoglobulin (-LG) and lactoferrin (LF) in the absence and presence of small ligands. The conditions of optimal ¿-LG - LF coacervation were found at pH range 5.4-6 with a molar excess of ¿-LG. RemarkabAt molecular level, the presence of two binding sites on LF for -LG was evidenced. Moreover, the heterocomplexes such as pentamers LF(-LG2)2 and quite large complexes (LF-LG2)n were identified as the constituent molecular species of the coacervate phase. To evaluate the -LG - LF complex coacervation in the presence of small ligands, models of hydrophobic (ANS) and hydrophilic molecules (folic acid) were used. Although under the experimental conditions tested the small ligands did not interact with -LG, both interacted with LF inducing its self-association into nanoparticles. High relati