Submitted by (lucia.rodrigues@ufrpe.br) on 2017-02-10T14:31:41Z No. of bitstreams: 1 Vania Freire Lemos.pdf: 1507844 bytes, checksum: cbb75eb979bd39586c08dadf5aea6579 (MD5) / Made available in DSpace on 2017-02-10T14:31:41Z (GMT). No. of bitstreams: 1 Vania Freire Lemos.pdf: 1507844 bytes, checksum: cbb75eb979bd39586c08dadf5aea6579 (MD5) Previous issue date: 2013-02-11 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / The objective of this work was to evaluate dynamics of the proteinogram of blood serum and whey protein of Santa Ines sheep breed following the antipartum period and during lactation, and to compare/to quantify proteins detected at eletrophoresis of the whey protein from healthy and infectious mammary glands in different phases of lactation. Thrirty four sheeps submitted to half-intensive system with same sanitary and nutritional management has been followed. For accomplishment of proteinogram of the sheep, they had been investigated during approximately 10 days from antipartum and 15, 30, 60 and 90 days postpartum, moments where clinical examination of mammary gland was carried through. Blood serum was evaluated at antipartum moment and proteinogram of whey protein at subsequent moments. Bacteriological culture and biochemist characterization of milk samples for confirmation of healthy and infected glands was performed. Separation of protein fractions was carried through using sodium dodecil sulphate polyacrylamide gel eletrophoresis (SDS-PAGE). For the blood serum it was observed quantification of nine proteins with significant influence in IgG. At whey protein, influence of the phases of lactation was identified eigth proteins, having albumin, IgG and β - lactoglobulin.. Comparing healthy and infected glands it was verified that hatptoglobin and α-1 acid glycoprotein, lactoferrin, albumin and immunoglobulins IgA and IgG in whey protein act as potentials biomarkers of infection in mammary gland of ovine species. / Objetivou-se neste trabalho avaliar a dinâmica do proteinograma do soro sangüíneo e lácteo de ovelhas da raça Santa Inês acompanhadas no período que antecedeu o parto e durante a lactação e comparar/quantificar as proteínas detectadas no traçado eletroforético do soro lácteo de glândulas mamárias sadias e infectadas em diferentes fases da lactação. Foram acompanhadas 34 ovelhas submetidas ao sistema de criação semi-intensivo, com mesmo manejo higiênico, sanitário e nutricional. Para a realização do proteinograma as ovelhas foram investigadas durante, aproximadamente 10 dias que precedeu o parto e 15, 30, 60 e 90 dias após o parto, momentos em que foi realizado o exame clínico da glândula mamária. O proteinograma sangüíneo foi efetuado a partir do momento pré parto e o proteinograma do soro lácteo nos momentos subseqüentes. Realizou-se o cultivo bacteriológico e a caracterização bioquímica das amostras de leite para confirmação de glândulas sadias e infectadas. A separação das frações protéicas foi realizada utilizando-se eletroforese em gel de poliacrilamida contendo dodecil sulfato de sódio (SDS-PAGE). Para o soro sanguíneo observou-se a quantificação de nove proteínas observando influência significativa somente na IgG; no soro lácteo identificou-se oito proteínas havendo influência das fases de lactação na albumina, IgG e β - lactoglobulina. Ccomparando glândulas sadias e infectadas verificou-se que a hatptoglobina, α-1 glicoproteína ácida, lactoferrina, albumina e as imunoglobulinas IgA e IgG presentes no soro lácteo atuam como biomarcadores de infecção na glândula mamária na espécie ovina.

O presente trabalho objetivou avaliar o efeito da adição de inulina (I) e a substituição parcial da gordura do leite (G) pelo concentrado de proteína de soro de leite (WPC) sobre a sobrevivência dos probióticos Lactobacillus acidophilus NCFM e Bifidobacterium animalis subsp. lactis HN019 em sorvete de graviola com teor reduzido de gordura, ao longo do período de armazenamento e frente às condições encontradas no trato gastrointestinal (TGI) simuladas in vitro. Adicionalmente, avaliou-se a influência desses ingredientes (6% I; 1,5% WPC; 3% e 1,5% G) sobre as características tecnológicas e a aceitabilidade do sorvete funcional. Empregou-se um planejamento fatorial 22, para 4 formulações produzidas, em triplicata, totalizando 12 ensaios: F1- controle (- I, - WPC); F2 (+ I, - WPC); F3 (- I, + WPC) e F4 (+ I, + WPC). Todas as formulações foram armazenadas a -18±3ºC e avaliadas após 2, 28, 56, 84 e 112 dias de armazenamento. A determinação das características tecnológicas foi realizada com as análises de dureza instrumental (em analisador de textura TA-XT2), fração de derretimento, overrun (durante a elaboração do produto) e perfil lipídico. Para o teste de aceitabilidade do produto, utilizou-se uma escala hedônica estruturada de 9 pontos. Elevada viabilidade probiótica foi observada para todas as formulações, com médias de populações acima de 8,0 log UFC/g, não diferindo significativamente durante o armazenamento de 112 dias (p>0,05). B. animalis subsp. lactis HN019 apresentou uma maior resistência em relação a L. acidophilus NCFM quando submetido aos sucos gastrointestinais artificiais, uma vez que a população de NCFM e de HN019 diminuíram, respectivamente, cerca de 5,2 log UFC/g e de 1,2 log UFC/g, durante o armazenamento. O efeito protetor do WPC e/ou I sobre a resistência de L. acidophilus aos sucos gastrointestinais artificiais foi observada no 56º dia e, para B. animalis subsp. lactis no 2º dia de armazenamento (p<0,05). Os sorvetes com WPC apresentaram menores valores de dureza, aos 7º e 112º dias de estocagem (p<0,05). A adição de inulina influenciou no aumento da dureza para F2 após 56 dias e para F4 durante todo período de armazenamento (p<0,05). Os resultados mostraram, também, que a presença do WPC e/ou inulina reduziu a velocidade de derretimento dos sorvetes durante todo o armazenamento (p<0,05). Elevados escores médios (entre 6,8 e 8,0) foram obtidos no teste de aceitabilidade sensorial dos sorvetes probióticos, indicando excelente aceitação pelos consumidores e não diferiram significativamente durante o armazenamento de até 84 dias. Já para F4, a adição do WPC + I aumentou a aceitação do produto após 56 dias (p<0,05). Os resultados obtidos sugerem que a utilização do WPC como substituto parcial da gordura láctea separadamente ou combinada com a inulina pode ser vantajosa no desenvolvimento de sorvete probiótico com baixo teor de gordura, uma vez que a presença desses ingredientes desempenhou um papel importante na proteção dos probióticos contra o efeito dos fluidos gastrointestinais nos testes in vitro. Além deste efeito protetor, a utilização da inulina e WPC também melhorou as características tecnológicas e sensoriais do sorvete funcional reduzido de gordura. / This study aimed to assess the effect of the addition of inulin (I) and the partial substitution of the milk fat (MF) by whey protein concentrate (WPC) on Lactobacillus acidophilus NCFM and Bifidobacterium animalis subsp. lactis HN019 viability incorporated in low fat graviola (Annona muricata L.) ice-cream and on probiotic survival under in vitro simulated gastrointestinal conditions throughout 112 days of storage. Moreover, the influence of these ingredients (6% I; 1,5% WPC; 3% and 1,5% MF) on the functional ice-cream technological and sensorial features was also evaluated. Employing a 22 factorial design, four formulations were produced, in triplicates: F1- control (- I, - WPC); F2 (+ I, - WPC); F3 (- I, + WPC) and F4 (+ I, + WPC). The product were stored at -18±3ºC and analyzed after 2, 28, 56, 84, and 112 days of storage. Ice-creams from each trial were used for determination of L. acidophilus and B. animalis subsp. lactis viability in the products and survival in ice-creams submitted to gastrointestinal simulated conditions during storage at -18±3ºC for up to 112 days. For the determination of technological features, instrumental hardness (in TA-XT2 Texture Analyser), melting rate, overrun (during production), and lipid profile were determined. For sensory acceptability evaluation, a 9 point hedonic scale was used. High probiotic viability was observed for all formulations, with mean populations above 8.0 cfu/g and which did not differ significantly throughout 112 days of storage (p>0.05). B. animalis subsp. lactis HN019 resistance to the artificial gastrointestinal juices was higher than for L. acidophilus NCFM, since the NCFM and the HN019 populations decreased approximately 5.2 log cfu/g and 1.2 log cfu/g, respectively, throughout storage. The protective effect of WPC and/or WPC + I on the L. acidophilus resistance to artificial gastrointestinal juices was observed on the 56th day and for B. animalis subsp. lactis on the 2nd day of storage (p<0.05). The ice-creams with WPC presented lower hardness in the 7th and 112nd days of frozen storage (p<0.05). The addition of inulin led to an incresed hardnes for F2 after 56 days and for F4 during the whole storage (p<0.05). The results also showed that the presence of the WPC and/or inulin reduced the ice-creams melting rates during the whole storage (p<0.05). The high mean scores obtained (between 6.8 and 8.0) in the acceptability test indicated that the functional ice-creams evaluated were very well accepted, and did not differ significantly throughout storage of up to 84 days. Except for F4, the addition of the WPC + I improved the acceptability after 56th days of frozen storage (p<0.05). The results suggest that the use of WPC for the partial substitution of the milk fat separately or combined with inulin may be advantageous in the development of low-fat synbiotic ice-cream, since the presence of these ingredients played an important role in the probiotic protection against gastrointestinal juices in the in vitro simulated assays. Besides these protective effects, inulin and WPC also improved the technological and sensory features of the low-fat functional ice-cream.

Submitted by Cássia Santos (cassia.bcufg@gmail.com) on 2015-02-26T14:26:31Z No. of bitstreams: 2 Tese - Gizelda de Siqueira Pedrosa Cardoso - 2014.pdf: 1778576 bytes, checksum: 2498b64eac789a9f7c7e2270a4e23dd0 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2015-03-02T11:38:36Z (GMT) No. of bitstreams: 2 Tese - Gizelda de Siqueira Pedrosa Cardoso - 2014.pdf: 1778576 bytes, checksum: 2498b64eac789a9f7c7e2270a4e23dd0 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2015-03-02T11:38:36Z (GMT). No. of bitstreams: 2 Tese - Gizelda de Siqueira Pedrosa Cardoso - 2014.pdf: 1778576 bytes, checksum: 2498b64eac789a9f7c7e2270a4e23dd0 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2014-10-30 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Milkagroindustrial sector is one of the largest agribusiness systems in the world. Brazil is traditionally a large producer of this noble food and even whey along with the production of cheese. This study aimed to evaluate the physical, chemical and microbiological composition of milk and milk whey, as well as, fresh and mozzarella cheeses stored under different temperature conditions. The experiment was conducted during two different periods of the year 2013. We carried out physico-chemical and microbiological analyzes in milk, and pH measurements, determination of titratable acidity, protein content, electrophoretic profile and microbiological analyzes in milk whey, after 21 days of storage at temperatures at 4±1 ºC and 8±1 ºC. Data were compared using intervals of 95% confidence, built in each time, from the Student t variable, and the analyzes performed using the R version of 3.0.3 software. The results of physical-chemical analysis of milk samples analyzed indicated rates at odds with current legislation. In microbial count, both milk and milk whey studied presented values of non-compliance with legislation. Throughout the storage period, only the whey of fresh cheese, stored at 4±1 ºC showed compliance with the rules for pH and titratable acidity. The average levels of total protein in the whey of cheeses studied at temperatures of 4±1 ºC and 8±1 ºC were in accordance with the rules and, regardless of the type of cheese, no significant differences in protein (p > 0.05 ), was verified throughout the observation period. The electrophoretic profile of milk whey allows observation of a greater concentration in the bands representing up to the seventh day of storage at 09 th to 11th proteins with molecular weights of between 14.4 to 116 kDa in both gels produced. / O setor agroindustrial do leite representa um dos maiores sistemas agroindustriais do mundo. O Brasil é, tradicionalmente, um grande produtor deste nobre alimento e, inclusive de soro lácteo juntamente com a produção de queijo. Objetivou-se avaliar a composição físico-química e microbiológica do leite e dos soros lácteos dos queijos minas frescal e mussarela estocado sob diferentes condições de temperatura. O experimento foi conduzido durante dois períodos distintos do ano de 2013. No leite foram realizadas análises físico-químicas e microbiológicas. Nos soros lácteos, acompanhados por 21 dias de estocagem nas temperaturas de 4±1ºC e 8±1ºC, foram realizadas aferições de pH, determinações da acidez titulável, teor protéico, perfil eletroforético e análises microbiológicas. Os dados foram comparados por meio de intervalos de 95% de confiança, construídos, em cada tempo, a partir da variável t-Student, e as análises realizadas com o software R versão 3.0.3. Os resultados das análises físico-químicas das amostras dos leites analisados indicaram índices em desacordo com a legislação vigente. Na contagem microbiana, tanto o leite como os soros lácteos estudados apresentaram valores de não conformidade com a legislação. Durante todo o período de estocagem, somente o soro do queijo minas frescal, armazenado a 4±1 ºC apresentou conformidade com a legislação para o pH e acidez titulável. Os teores médios de proteína total nos soros dos queijos pesquisados, nas temperaturas de 4±1 ºC e 8±1 ºC apresentaram-se em acordo com a legislação e, independente do tipo de queijo, não apresentaram diferenças significativas de proteínas (p> 0,05), ao longo do período de observação. O perfil eletroforético dos soros lácteos permitiu a observação de uma concentração mais acentuada nas bandas representativas de até o sétimo dia de armazenamento com 09 a 11 proteínas com pesos moleculares entre 14,4 a 116 kDa, em ambos os géis produzidos.

Made available in DSpace on 2017-07-10T19:25:13Z (GMT). No. of bitstreams: 1 henry.pdf: 2217836 bytes, checksum: f01d367fdd6ecd64b7d0ccf6ae52d669 (MD5) Previous issue date: 2012-07-02 / In Brazil, the grain harvest in 2007/08 was about 145 million tons, a record for the domestic agriculture. In 2008 soybeans led to participation in the value of production of temporary and permanent crops with 39.18% which were superseded by the 2009/2010, in which the Paraná state reached the first place in soybean production in Brazil. As possible benefits of diets containing soy we could mention the anticarcinogenic effects, reduction of cholesterol levels, protective effects against obesity and symptoms such as hot flashes during menopause, treatment of coronary heart disease and osteoporosis. According to this economic and health context, this work aimed the development of a hydrosoluble soybean extract fermented with probiotic microorganisms, plus inulin (prebiotic substance) and whey protein concentrate, in order to meet the consumers expectations on health, nutrition and functionality due to their symbiotic nature. Physical and chemical, microbiological, sensory analyzes and probiotic bacteria counting were carried out, considering different types of sugars such as sucrose and glucose. Twelve formulations were prepared from hydrosoluble soybean extract with whey protein concentrate and inulin, by varying the inoculated cultures (Lactobacillus acidophilus, Lactobacillus casei and SAB) and sugar (100% glucose treatment, 100% sucrose treatment, 50% glucose and 50% sucrose treatment, and 0% sugar treatment). The sensory evaluation experiment was completely randomized, applying analysis of variance-ANOVA and Means Test (Tuckey). In the fermentation process the formulation A5 (EHS 10%, 2.5% WPC, 2% inulin, sugar and inoculum SAB) presented the shortest time register, with 5 hours and 53 minutes to achieve the optimum pH. For an optimal therapeutic effect, it is estimated that the probiotic food must contain a number above than 107 CFU / mL, and all formulations reached this viable cell count during 28 days of storage, especially the Treatment A9 with an initial count of 1,20 x1014 CFU / mL. The increased acidity values reached 85 ºD, maintaining the pH value close to 4.31, which means a suitable pH. The results of the microbiological analyzes of fermented beverages were in accordance to the standards established by the Brazilian legislation, ensuring the safety of the samples. The rate of acceptance achieved by sensory evaluation of the beverages was above 70% considering the formulations A2 (EHS 10%, 2.5% WPC, 2% of inulin, 100% sucrose and L. casei inoculum) and A10 (EHS 10% 2.5% WPC, 2% of inulin, and 100% sucrose and L. acidophilus inoculum), which means that these formulations would be well accepted in the consumers market. / A safra brasileira de grãos 2007/08 foi de cerca de 145 milhões de toneladas, um recorde para a agricultura interna. No ano de 2008 a soja liderou a participação no valor da produção de lavouras temporárias e permanentes com 39,18%, participação que foi superada pela safra 2009/2010, na qual o Paraná garantiu o primeiro lugar na produção de soja no Brasil. Como possíveis benefícios de dietas contendo soja podem ser mencionados os efeitos anticarcinogênicos, redução dos níveis de colesterol, efeitos protetores contra a obesidade e sintomas como ondas de calor na menopausa, tratamento de doenças coronarianas e osteoporose. Diante deste contexto econômico e de saúde, almejou-se desenvolver uma bebida à base de extrato hidrossolúvel de soja fermentada com micro-organismos probióticos, acrescida de inulina (substância prebiótica) e proteína concentrada do soro do leite, visando atender às expectativas de consumidores quanto à saúde, nutrição e funcionalidade, devido ao seu caráter simbiótico. Foram realizadas análises físico-químicas, microbiológicas, sensoriais e contagem de bactérias probióticas, considerando-se diferentes tipos de açúcares, como sacarose e glicose. Foram elaboradas doze formulações a partir de extrato hidrossolúvel de soja, adicionado de proteína concentrada de soro de leite e inulina, variando as culturas inoculadas (fermentos lácteos Lactobacillus acidophilus, Lactobacillus casei e SAB) e o açúcar (Tratamento com 100% de glicose, tratamento com 100% de sacarose, tratamento com 50% de glicose e 50% de sacarose e tratamento com 0% de açúcar). O delineamento experimental na avaliação sensorial foi inteiramente casualizado, aplicando-se a análise de variância (ANOVA) e teste de médias (Tuckey). No processo de fermentação a formulação contendo 10% EHS, 2,5% WPC, 2% de inulina, sem açúcar e o inóculo SAB sobressaiu-se com o menor tempo, totalizando 5 horas e 53 minutos para alcançar o pH ótimo. Para obter um efeito terapêutico ótimo, estima-se que o alimento probiótico deva conter um número maior que 107 UFC/mL, sendo que todas as formulações elaboradas alcançaram este propósito durante os 28 dias de armazenamento, tendo como destaque a formulação A9 com uma contagem inicial de 1,20 x1014 UFC/mL. Os valores de acidez aumentaram até aproximadamente 85º D, mantendo o valor de pH próximo a 4,31, o que significa um pH adequado. Os resultados das análises microbiológicas das bebidas fermentadas apresentaram-se em conformidade com os padrões estabelecidos pela legislação brasileira, assegurando a inocuidade das amostras. O índice de aceitabilidade obtido pela avaliação sensorial das bebidas foi superior a 70% para as formulações A2 (10% EHS, 2,5% WPC, 2% de inulina, 100% sacarose e o inóculo L. casei ) e A10 (10% EHS, 2,5%WPC,2% de inulina, 100%sacarose e o inóculo L. acidófilos), o que significa que estas formulações seriam bem aceitas no mercado consumidor.

Made available in DSpace on 2017-05-12T14:48:38Z (GMT). No. of bitstreams: 1 henry.pdf: 2217836 bytes, checksum: f01d367fdd6ecd64b7d0ccf6ae52d669 (MD5) Previous issue date: 2012-07-02 / In Brazil, the grain harvest in 2007/08 was about 145 million tons, a record for the domestic agriculture. In 2008 soybeans led to participation in the value of production of temporary and permanent crops with 39.18% which were superseded by the 2009/2010, in which the Paraná state reached the first place in soybean production in Brazil. As possible benefits of diets containing soy we could mention the anticarcinogenic effects, reduction of cholesterol levels, protective effects against obesity and symptoms such as hot flashes during menopause, treatment of coronary heart disease and osteoporosis. According to this economic and health context, this work aimed the development of a hydrosoluble soybean extract fermented with probiotic microorganisms, plus inulin (prebiotic substance) and whey protein concentrate, in order to meet the consumers expectations on health, nutrition and functionality due to their symbiotic nature. Physical and chemical, microbiological, sensory analyzes and probiotic bacteria counting were carried out, considering different types of sugars such as sucrose and glucose. Twelve formulations were prepared from hydrosoluble soybean extract with whey protein concentrate and inulin, by varying the inoculated cultures (Lactobacillus acidophilus, Lactobacillus casei and SAB) and sugar (100% glucose treatment, 100% sucrose treatment, 50% glucose and 50% sucrose treatment, and 0% sugar treatment). The sensory evaluation experiment was completely randomized, applying analysis of variance-ANOVA and Means Test (Tuckey). In the fermentation process the formulation A5 (EHS 10%, 2.5% WPC, 2% inulin, sugar and inoculum SAB) presented the shortest time register, with 5 hours and 53 minutes to achieve the optimum pH. For an optimal therapeutic effect, it is estimated that the probiotic food must contain a number above than 107 CFU / mL, and all formulations reached this viable cell count during 28 days of storage, especially the Treatment A9 with an initial count of 1,20 x1014 CFU / mL. The increased acidity values reached 85 ºD, maintaining the pH value close to 4.31, which means a suitable pH. The results of the microbiological analyzes of fermented beverages were in accordance to the standards established by the Brazilian legislation, ensuring the safety of the samples. The rate of acceptance achieved by sensory evaluation of the beverages was above 70% considering the formulations A2 (EHS 10%, 2.5% WPC, 2% of inulin, 100% sucrose and L. casei inoculum) and A10 (EHS 10% 2.5% WPC, 2% of inulin, and 100% sucrose and L. acidophilus inoculum), which means that these formulations would be well accepted in the consumers market. / A safra brasileira de grãos 2007/08 foi de cerca de 145 milhões de toneladas, um recorde para a agricultura interna. No ano de 2008 a soja liderou a participação no valor da produção de lavouras temporárias e permanentes com 39,18%, participação que foi superada pela safra 2009/2010, na qual o Paraná garantiu o primeiro lugar na produção de soja no Brasil. Como possíveis benefícios de dietas contendo soja podem ser mencionados os efeitos anticarcinogênicos, redução dos níveis de colesterol, efeitos protetores contra a obesidade e sintomas como ondas de calor na menopausa, tratamento de doenças coronarianas e osteoporose. Diante deste contexto econômico e de saúde, almejou-se desenvolver uma bebida à base de extrato hidrossolúvel de soja fermentada com micro-organismos probióticos, acrescida de inulina (substância prebiótica) e proteína concentrada do soro do leite, visando atender às expectativas de consumidores quanto à saúde, nutrição e funcionalidade, devido ao seu caráter simbiótico. Foram realizadas análises físico-químicas, microbiológicas, sensoriais e contagem de bactérias probióticas, considerando-se diferentes tipos de açúcares, como sacarose e glicose. Foram elaboradas doze formulações a partir de extrato hidrossolúvel de soja, adicionado de proteína concentrada de soro de leite e inulina, variando as culturas inoculadas (fermentos lácteos Lactobacillus acidophilus, Lactobacillus casei e SAB) e o açúcar (Tratamento com 100% de glicose, tratamento com 100% de sacarose, tratamento com 50% de glicose e 50% de sacarose e tratamento com 0% de açúcar). O delineamento experimental na avaliação sensorial foi inteiramente casualizado, aplicando-se a análise de variância (ANOVA) e teste de médias (Tuckey). No processo de fermentação a formulação contendo 10% EHS, 2,5% WPC, 2% de inulina, sem açúcar e o inóculo SAB sobressaiu-se com o menor tempo, totalizando 5 horas e 53 minutos para alcançar o pH ótimo. Para obter um efeito terapêutico ótimo, estima-se que o alimento probiótico deva conter um número maior que 107 UFC/mL, sendo que todas as formulações elaboradas alcançaram este propósito durante os 28 dias de armazenamento, tendo como destaque a formulação A9 com uma contagem inicial de 1,20 x1014 UFC/mL. Os valores de acidez aumentaram até aproximadamente 85º D, mantendo o valor de pH próximo a 4,31, o que significa um pH adequado. Os resultados das análises microbiológicas das bebidas fermentadas apresentaram-se em conformidade com os padrões estabelecidos pela legislação brasileira, assegurando a inocuidade das amostras. O índice de aceitabilidade obtido pela avaliação sensorial das bebidas foi superior a 70% para as formulações A2 (10% EHS, 2,5% WPC, 2% de inulina, 100% sacarose e o inóculo L. casei ) e A10 (10% EHS, 2,5%WPC,2% de inulina, 100%sacarose e o inóculo L. acidófilos), o que significa que estas formulações seriam bem aceitas no mercado consumidor.

The present study was aimed at extending our knowledge of the antioxidative properties of the milk protein products, whey protein isolate (WPI) and sodium caseinate (NaCas), in oil-in-water (O/W) emulsions rich in polyunsaturated fatty acids (PUFAs). In particular, the objective was to contribute to our understanding of the compositional and processing factors that influence the oxidative stability of protein-stabilised O/W emulsions. Linoleic acid (approximately 60 %) was used as the lipid for the oil phase (10.6 %). The emulsion samples were usually incubated at 50 °C to accelerate lipid oxidation. Lipid oxidation indicators were lipid hydroperoxides and headspace hexanal, determined by solid phase microextraction (SPME) combined with gas chromatography (GC). WPI- or NaCas-stabilised emulsions were prepared using a wide range of protein concentrations (0.5, 1.0, 2.0, 3.0, 4.0, 7.0 or 10.0 %) at two droplet sizes (d32 = 0.31 and 0.65 µm). In general, higher lipid oxidation levels were found for the larger droplet size. Increasing protein concentration led to a decrease in the lipid oxidation rate. The greatest decrease in lipid hydroperoxide levels (values after 4 h) occurred at up to 4.0 % protein concentration. The greatest decrease in hexanal levels (values after 24 h) occurred at up to 4.0 % protein concentration in WPI emulsions (0.31 µm). The hexanal levels were more independent of the protein concentration in the other emulsion types. The hexanal level decreased at protein concentrations > 4.0 % in NaCas emulsions (0.31 and 0.65 µm) and at protein concentrations > 7.0 % in WPI emulsions (0.65 µm). The difference between lipid hydroperoxide generation in emulsions with small and large droplet sizes decreased with increasing protein concentration. This effect was more pronounced in NaCas emulsions. In general, NaCas was a better inhibitor of lipid oxidation than WPI, but WPI appeared to be the better antioxidant at some droplet size/protein concentration combinations. The protein in the continuous phase, i.e. the unadsorbed protein, played an important role in lipid oxidation. In principal, the lipid hydroperoxide and hexanal levels showed the same development over the continuous phase protein concentration as over the protein concentration in WPI and NaCas emulsions (d32 = 0.31 µm). A low NaCas level in the continuous phase already led to a relatively low hexanal level, whereas a higher WPI level was required. When NaCas solution was added to a WPI emulsion or WPI solution was added to a NaCas emulsion, a synergistic antioxidative effect was observed. The high molecular weight fractions (molecular weight = 12000-14000) of WPI and NaCas contained pro-oxidative metal ions that contributed to lipid oxidation in the emulsions. An enrichment of NaCas emulsions with the low molecular weight fraction of NaCas (with a molecular weight = 12000-14000) notably inhibited lipid oxidation. An enrichment of WPI emulsions with the low molecular weight fraction of WPI (with a molecular weight = 12000-14000) also seemed to inhibit lipid oxidation, but the effect was not significant. The protein solutions were enriched with these fractions before emulsion preparation. Pure WPI solution or mixed WPI/NaCas (1:1, weight/weight) solution with 1.12 or 2.24 % protein concentration was heated at 84 °C for up to 40 min, cooled and then used to prepare emulsions. Lipid oxidation was generally not affected by the heat treatment or the degree of whey protein denaturation. However, at the lower WPI concentration, more hexanal was produced for the longer heating times (20, 30 and 40 min) and this appeared to be connected with the physical instability of the emulsions. Greater oxidative stability was found at the higher protein concentration and when the proteins were mixed, pointing to a possible synergistic antioxidative effect of WPI and NaCas. The addition of the free radical source 2,2’-azobis(2-amidinopropane) dihydrochloride (AAPH) greatly increased the oxygen uptake and the generation of lipid hydroperoxides in the emulsions. The oxidative stability increased with increasing protein concentration (1.0, 4.0 and 7.0 %). NaCas had a greater antioxidative effect than WPI. The inhibition of oxygen uptake appeared to be largely influenced by the free-radical-scavenging activity of the system, determined by the protein type and the protein concentration, as the radicals were produced linearly over time and oxygen was consumed linearly over time. It can therefore be concluded that free-radical-scavenging activity represents a major antioxidative mechanism of the milk proteins. Oxygen was consumed much faster in emulsions than in protein solutions when the same level of AAPH was incorporated. In a WPI (1.0 % protein) emulsion, much lower levels of protein hydroperoxides than of lipid hydroperoxides developed. This pointed to a much greater reactivity of linoleic acid than of the milk proteins with oxygen. In contrast, the exposure of WPI to oxidising linoleic acid in an emulsion (1.0 % protein) or to AAPH in aqueous solution led to oxidative damage of the whey proteins, indicated by the loss of amino acids. The loss of specific amino acids was different for proteins in the continuous phase or cream phase of an emulsion or in WPI solution. The present study confirms the antioxidative potential of WPI and NaCas and gives new insights into their functionality as oxidative stabilisers in O/W emulsions.

Chitosan, Whey Protein Isolate (WPI) and vital wheat gluten (WG) are three biomaterials that have quite promising properties for packaging purposes. They have good film forming properties and good gas barrier properties in dry conditions. Moreover, because they are produced from industrial waste of food processing, they offer an ecological advantage over polymers made from petroleum. However, their physicochemical characteristics still must be improved for them to be of commercial interest for the food packaging industry. The purpose of this work was to study different strategies aiming to improve the water resistance and aging properties of these polymers, which are some of the key disadvantages of these materials. The produced solution cast chitosan and WPI films were characterised with scanning electron microscopy (SEM), density measurements and thermogravimetry. The water vapour transmission rate was determined at a relative humidity of 11%. In the first part, mechanical properties of solid films and seals were assessed by tensile testing. WG film’s tensile properties and oxygen and water vapour permeabilities were measured as a function of aging time. The changes in the protein structure were determined by infrared spectroscopy and size-exclusion high-performance liquid chromatography and the film structure was revealed by optical and scanning electron microscopy. Gluten-clay nanocomposites were characterised by tensile testing, X-ray diffraction and transmission electron microscopy. The incorporation of a hydrophobic biodegradable polymer, poly ( ε-caprolactone), PCL, in both chitosan and whey protein, yielded a significant decrease in water vapour transmission rate. It was observed that a certain amount of the PCL particles were ellipsoidal in chitosan and fibrous in WPI. The obtained data also indicated that the particle shape had an important influence in the water vapour transmission rate. In the second part, the aging properties of WG films, plasticized with glycerol and cast from water/ethanol solutions with pH=4 or pH=11 were investigated. WG films made from alkaline solutions were mechanically more time-stable than the acidic ones, the latter being initially very ductile but turning brittle towards the end of the aging period. The protein solubility measurements indicated that the protein structure of the acidic films was initially significantly less aggregated than the in basic films. During aging the acidic films lost more mass than the basic films through slow evaporation of volatiles (water/ethanol) and through migration of glycerol to the paper support. The oxygen permeability was also lower for the basic films. In the last part, the properties of new and aged glycerol-plasticized WG films at acidic and basic conditions containing ≤4.5 wt% natural or quaternary-ammonium-salt-modified montmorillonite were studied. Films of WG with montmorillonite were possible to produce by solution casting. The aging rate of acidic and basic films was unaffected by the incorporation of clay. However, the large reduction in water vapour permeability for most systems suggested that the clay sheets were evenly distributed within the films. The film prepared from basic solution and containing natural clay was almost completely exfoliated as revealed by transmission electron microscopy and X-ray diffraction. The best water vapour barrier properties were obtained by using modified clay. / QC 20101013

The present study was aimed at extending our knowledge of the antioxidative properties of the milk protein products, whey protein isolate (WPI) and sodium caseinate (NaCas), in oil-in-water (O/W) emulsions rich in polyunsaturated fatty acids (PUFAs). In particular, the objective was to contribute to our understanding of the compositional and processing factors that influence the oxidative stability of protein-stabilised O/W emulsions. Linoleic acid (approximately 60 %) was used as the lipid for the oil phase (10.6 %). The emulsion samples were usually incubated at 50 °C to accelerate lipid oxidation. Lipid oxidation indicators were lipid hydroperoxides and headspace hexanal, determined by solid phase microextraction (SPME) combined with gas chromatography (GC). WPI- or NaCas-stabilised emulsions were prepared using a wide range of protein concentrations (0.5, 1.0, 2.0, 3.0, 4.0, 7.0 or 10.0 %) at two droplet sizes (d32 = 0.31 and 0.65 µm). In general, higher lipid oxidation levels were found for the larger droplet size. Increasing protein concentration led to a decrease in the lipid oxidation rate. The greatest decrease in lipid hydroperoxide levels (values after 4 h) occurred at up to 4.0 % protein concentration. The greatest decrease in hexanal levels (values after 24 h) occurred at up to 4.0 % protein concentration in WPI emulsions (0.31 µm). The hexanal levels were more independent of the protein concentration in the other emulsion types. The hexanal level decreased at protein concentrations > 4.0 % in NaCas emulsions (0.31 and 0.65 µm) and at protein concentrations > 7.0 % in WPI emulsions (0.65 µm). The difference between lipid hydroperoxide generation in emulsions with small and large droplet sizes decreased with increasing protein concentration. This effect was more pronounced in NaCas emulsions. In general, NaCas was a better inhibitor of lipid oxidation than WPI, but WPI appeared to be the better antioxidant at some droplet size/protein concentration combinations. The protein in the continuous phase, i.e. the unadsorbed protein, played an important role in lipid oxidation. In principal, the lipid hydroperoxide and hexanal levels showed the same development over the continuous phase protein concentration as over the protein concentration in WPI and NaCas emulsions (d32 = 0.31 µm). A low NaCas level in the continuous phase already led to a relatively low hexanal level, whereas a higher WPI level was required. When NaCas solution was added to a WPI emulsion or WPI solution was added to a NaCas emulsion, a synergistic antioxidative effect was observed. The high molecular weight fractions (molecular weight = 12000-14000) of WPI and NaCas contained pro-oxidative metal ions that contributed to lipid oxidation in the emulsions. An enrichment of NaCas emulsions with the low molecular weight fraction of NaCas (with a molecular weight = 12000-14000) notably inhibited lipid oxidation. An enrichment of WPI emulsions with the low molecular weight fraction of WPI (with a molecular weight = 12000-14000) also seemed to inhibit lipid oxidation, but the effect was not significant. The protein solutions were enriched with these fractions before emulsion preparation. Pure WPI solution or mixed WPI/NaCas (1:1, weight/weight) solution with 1.12 or 2.24 % protein concentration was heated at 84 °C for up to 40 min, cooled and then used to prepare emulsions. Lipid oxidation was generally not affected by the heat treatment or the degree of whey protein denaturation. However, at the lower WPI concentration, more hexanal was produced for the longer heating times (20, 30 and 40 min) and this appeared to be connected with the physical instability of the emulsions. Greater oxidative stability was found at the higher protein concentration and when the proteins were mixed, pointing to a possible synergistic antioxidative effect of WPI and NaCas. The addition of the free radical source 2,2’-azobis(2-amidinopropane) dihydrochloride (AAPH) greatly increased the oxygen uptake and the generation of lipid hydroperoxides in the emulsions. The oxidative stability increased with increasing protein concentration (1.0, 4.0 and 7.0 %). NaCas had a greater antioxidative effect than WPI. The inhibition of oxygen uptake appeared to be largely influenced by the free-radical-scavenging activity of the system, determined by the protein type and the protein concentration, as the radicals were produced linearly over time and oxygen was consumed linearly over time. It can therefore be concluded that free-radical-scavenging activity represents a major antioxidative mechanism of the milk proteins. Oxygen was consumed much faster in emulsions than in protein solutions when the same level of AAPH was incorporated. In a WPI (1.0 % protein) emulsion, much lower levels of protein hydroperoxides than of lipid hydroperoxides developed. This pointed to a much greater reactivity of linoleic acid than of the milk proteins with oxygen. In contrast, the exposure of WPI to oxidising linoleic acid in an emulsion (1.0 % protein) or to AAPH in aqueous solution led to oxidative damage of the whey proteins, indicated by the loss of amino acids. The loss of specific amino acids was different for proteins in the continuous phase or cream phase of an emulsion or in WPI solution. The present study confirms the antioxidative potential of WPI and NaCas and gives new insights into their functionality as oxidative stabilisers in O/W emulsions.

Milk is provided to new borns as their first food source and it contains essential nutrients, vitamins and other beneficial components, such as enzymes and antibodies that are required for rapid growth and development of the new born and for sustained growth over time. Milk contains two main types of proteins; casein proteins and whey proteins. Although casein proteins account for up to 80% of the proteins found in bovine milk, it is the whey protein that has become of high interest because of its bioactive content. Whey, a very watery mixture of lactose, proteins, minerals and trace amounts of fat, is formed from milk when the milk is coagulated and/or the casein proteins are removed from the milk. Bovine whey protein, including both the acidic and basic fractions (low and high isoelectric point, respectively), has previously been studied in vitro (cell based) and in vivo (using rats) for its impact on bone to determine if it can help improve bone mineral density and help reduce the risk of developing bone diseases, such as osteoporosis. Bone is constantly undergoing a remodelling process of being dissolved and reformed and the two main cell types responsible for this bone remodelling process are mature osteoclasts, which dissolve (resorb) bone, and osteoblasts, which reform the bone. Prior work has shown that acidic protein fractions derived from different sources of whey protein concentrate (WPC) have both in vivo and in vitro activity on bone, particularly anti-resorptive properties. However, the component(s) which confer activity have not yet been identified. In this thesis, work was undertaken to better understand the analytical composition of three types of WPC (cheese, mineral acid and lactic acid) and their associated acidic protein fractions and relate this to bone activity in the hope of identifying where the activity lies. Bone activity was assessed using in vitro screening with osteoblast cells (MC3T3-E1) and osteoclast cells (RAW 264.7). Comparison of the cell-based bone activity of the parent WPCs and corresponding acidic fractions indicated that the acidic fractions derived from both mineral acid and lactic WPC were superior in their ability to inhibit osteoclast development. Although compositional data was complex and definitive correlations with both bone bioactivities could not be made, it appeared that elements common to both the acidic fractions were a higher proportion of GLYCAM-1 and bone sialoprotein-1 (osteopontin). Further studies to more closely investigate the bone bioactivity of the acidic fractions are warranted.

Milk is provided to new borns as their first food source and it contains essential nutrients, vitamins and other beneficial components, such as enzymes and antibodies that are required for rapid growth and development of the new born and for sustained growth over time. Milk contains two main types of proteins; casein proteins and whey proteins. Although casein proteins account for up to 80% of the proteins found in bovine milk, it is the whey protein that has become of high interest because of its bioactive content. Whey, a very watery mixture of lactose, proteins, minerals and trace amounts of fat, is formed from milk when the milk is coagulated and/or the casein proteins are removed from the milk. Bovine whey protein, including both the acidic and basic fractions (low and high isoelectric point, respectively), has previously been studied in vitro (cell based) and in vivo (using rats) for its impact on bone to determine if it can help improve bone mineral density and help reduce the risk of developing bone diseases, such as osteoporosis. Bone is constantly undergoing a remodelling process of being dissolved and reformed and the two main cell types responsible for this bone remodelling process are mature osteoclasts, which dissolve (resorb) bone, and osteoblasts, which reform the bone. Prior work has shown that acidic protein fractions derived from different sources of whey protein concentrate (WPC) have both in vivo and in vitro activity on bone, particularly anti-resorptive properties. However, the component(s) which confer activity have not yet been identified. In this thesis, work was undertaken to better understand the analytical composition of three types of WPC (cheese, mineral acid and lactic acid) and their associated acidic protein fractions and relate this to bone activity in the hope of identifying where the activity lies. Bone activity was assessed using in vitro screening with osteoblast cells (MC3T3-E1) and osteoclast cells (RAW 264.7). Comparison of the cell-based bone activity of the parent WPCs and corresponding acidic fractions indicated that the acidic fractions derived from both mineral acid and lactic WPC were superior in their ability to inhibit osteoclast development. Although compositional data was complex and definitive correlations with both bone bioactivities could not be made, it appeared that elements common to both the acidic fractions were a higher proportion of GLYCAM-1 and bone sialoprotein-1 (osteopontin). Further studies to more closely investigate the bone bioactivity of the acidic fractions are warranted.