Made available in DSpace on 2014-12-17T15:01:51Z (GMT). No. of bitstreams: 1 PriscillaDLS_TESE_Partes autorizadas.pdf: 314555 bytes, checksum: 661601c05f1dc510316e74f62a201622 (MD5) Previous issue date: 2011-02-25 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / This work targetet the caprine ice cream production added with probiotic bacteria Bifidobacterium animalis subsp. lactis. It is divided into two parts. In the first one, four caprine ice cream formulations were evaluated, in which it was used hydrogenated fat (F1 and F3) or fat substitute (F2 and F4) in two different flavors (F1 and F2, passion fruit, F3 and F4, guava). Statistical differences (p<0.05) were detected for their physical-chemical properties, mainly for total solids and fat, but no differences were observed for melting test results. When it went to sensory acceptance, all four ice cream formulations reached high acceptance indexes, mostly formulation F4, which was selected for further studies. In the second part, F4 formulation was prepared with the addition of probiotic bacteria Bifidobacterium animalis subsp. lactis. The growth kinetics was studied and it was observed that the cellular concentration peak was reached after four fermentation hours (10.14 log UFC/g). This time was selected for pre-fermentation procedure and posterior addition at ice cream syrup. In this part of the study, two experimental groups were evaluated: group G1, in which the probiotic addition occurred before the maturation step and group G2, which included a pre-fermentation step and probiotic addition after ice cream maturation. The physical-chemical properties of these two ice cream groups were similar, except for pH, which was higher for group G2 (p<0.05). G1 samples had superior melting rate (3.566 mL/min) and both groups presented microbiological and sanitary results in accordance to current Brazilian legislation. Also, G1 and G2 were considered sensory accepted due to their acceptance indexes higher than 70%. G1 and G2 sensory profiles were similar (p>0.05), and both ice cream samples exhibited high creaminess (6.76 to 6.91) and mouth melting sensation (6.53 to 6.67) scores, while low sandiness scores (0.85 to 0.86) were observed, positive characteristics for this kind of food product. During the first 24 hours after ice cream production, the population of B. animalis subsp. lactis decreased, reaching 7.15 e 6.92 log CFU/g for G1 and G2, respectively. Probiotic bacteria counts fluctuated in ice cream samples during the first 108 days at frozen storage, especially for G2 group. Decreased probiotic viability was observed for G1 samples during the first 35 days of frozen storage, mild variation between 35 and 63 days and stabilized counts were observed after this time. After 21 days at frozen storage, ice cream samples of G1 and G2 groups reached 1.2 x 109 and 1.3 x 109 CFU/portion, respectively. After 108 days under these storage conditions, the survival rate of B. animalis subsp. lactis was 94.26% and 81.10% for G1 and G2 samples, respectively. After simulation of gastroenteric conditions, G2 group reached 9.72 x 105 CFU/portion. Considering the current requirements of Brazilian legislation, which stipulates that functional foods must have minimum probiotic count between 108 and 109 CFU/portion and detectable probiotic bacteria after being submitted to gastroenteric conditions, it is concluded that the ice cream with the addition of Bifidobacterium animalis subsp. lactis made as shown in this work, can be considered as a dairy functional food / O presente trabalho teve o objetivo de estudar a produ??o de sorvete elaborado com leite caprino com adi??o da bact?ria probi?tica Bifidobacterium animalis subsp. lactis. Foi estruturado em duas etapas. Inicialmente foram avaliadas quatro formula??es de sorvete, nas quais foi utilizada gordura vegetal hidrogenada (F1 e F3) e substituto de gordura (F2 e F4) em dois sabores (F1 e F2, maracuj?; F3 e F4, goiaba). Os c?lculos de densidade aparente e overrun foram feitos levando em considera??o as especifica??es da RDC n?. 266 de setembro de 2005. Tamb?m foram realizadas determina??es de pH, acidez total titul?vel e s?lidos totais, s?lidos sol?veis e res?duo por incinera??o, m?todo Kjeldahl para determina??o de prote?na bruta, lip?dios, a??cares redutores e totais. Al?m destas an?lises foram realizados o teste de derretimento e as an?lises microbiol?gicas nos sorvetes elaborados. As formula??es apresentaram diferen?as significativas (p<0,05) quanto ? composi??o f?sico-qu?mica, sobretudo no que diz respeito ao teor de s?lidos totais e gordura, mas n?o foi observada influ?ncia da formula??o sobre o perfil de derretimento das amostras. Quanto ? avalia??o sensorial, as quatro formula??es apresentaram elevados ?ndices de aceita??o, sobretudo a formula??o F4. Essa formula??o foi selecionada para dar prosseguimento aos estudos, cujo objetivo foi estudar os procedimentos de elabora??o do sorvete de leite de cabra com adi??o de B. animalis subsp. lactis. O pico de concentra??o celular (10,14 log UFC/g) foi alcan?ado ap?s quatro horas de cultivo sendo esse ponto escolhido para o procedimento de pr?-fermenta??o e adi??o de B. animalis subsp. lactis na calda do sorvete. Foram avaliados dois grupos experimentais de sorvete caprino com adi??o de probi?ticos: o grupo G1, com adi??o das bifidobact?rias antes da matura??o e G2, com etapa de pr?-fermenta??o e adi??o ap?s a matura??o. As propriedades f?sico-qu?micas dos dois grupos foram similares, com exce??o do pH, cujo valor foi superior no grupo G2 (p<0,05). O grupo G1 apresentou maior (p<0,05) taxa de derretimento (3,566 mL/min) e ambos os tratamentos apresentaram padr?es microbiol?gicos e sanit?rios dentro do exigido pela legisla??o vigente. Os dois grupos foram considerados aceitos sensorialmente, por exibirem n?veis de aceita??o superiores a 70% em todos os atributos verificados. Os perfis sensoriais das amostras G1 e G2 foram semelhantes (p>0,05), com elevados escores para os atributos cremosidade (6,76 a 6,91) e derretimento na boca (6,53 a 6,67), al?m de pontua??o reduzida para o quesito arenosidade (0,85 a 0,86), resultados considerados positivos para esse tipo de alimento. Foi observado decr?scimo da popula??o de B. animalis subsp. lactis ap?s as primeiras 24 horas de produ??o com contagens de 7,15 e 6,92 log UFC/g para G1 e G2, respectivamente. A contagem de bact?rias probi?ticas apresentou varia??es ao longo do armazenamento congelado por 108 dias, sobretudo para o grupo G2. O grupo G1, por sua vez, apresentou queda de viabilidade durante os primeiros 35 dias de congelamento, leve varia??o entre 35 e 63 dias de armazenamento e tend?ncia ? estabiliza??o ap?s esse ponto. Ap?s 21 dias sob armazenamento congelado, as amostras G1 e G2 apresentaram contagem de 1,2 x 109 e 1,3 x 109 UFC/por??o, respectivamente, conforme determina a legisla??o para contagens m?nimas por por??o de comest?veis gelados. Por sua vez, ao final de 108 dias sob essas condi??es, as taxas de sobreviv?ncia do B. animalis subsp. lactis do grupo G1 e G2 foram respectivamente, 94,26% e 81,10%. Ap?s ser submetido a condi??es g?stricas e ent?ricas simuladas in vitro, o sorvete com quatro meses de armazenamento do tratamento G2 apresentou contagem 9,72 x 105 UFC/por??o. Considerando o disposto pela legisla??o nacional vigente, segundo a qual um alimento com alega??o funcional deve possuir contagem m?nima probi?tica entre 108 e 109 UFC/por??o e exist?ncia de microrganismos vi?veis ap?s exposi??o ?s condi??es gastroent?ricas, conclui-se que o sorvete com adi??o de B. animalis subsp. lactis, produzido no presente estudo, constitui alimento l?cteo funcional

Infant formula (IF) is a commonly used replacement whenever mother’s own milk is not available. Most IFs are based on cow milk (powders, liquids). Alternatives, based on other sources such as goat milk or plants, exist. Independent of the source, IF production and composition are strictly regulated. Besides proteins, minerals, and lipids, milk contains a variety of endogenous peptides. Whereas the human milk peptidome has been studied intensively, the peptidomes of IFs have been mostly neglected. This study investigated the peptidomes of different types of first stage IF, including cow milk-based powders and liquids, and powdered goat milk-based IF, highlighting major similarities and differences to human milk. Extracted native peptidomes were analyzed by nanoRPC-ESI-MS/MS using two different fragmentation techniques allowing the confident identification of 1587 peptides. β-Casein peptides dominated in all samples. Interestingly, powdered and liquid cow milk-based IFs differed in the numbers of β- and αS1-casein peptides, indicating processing-derived variations. However, the peptidomes of cow and goat milk-based IF appeared to be more comparable to each other than to human milk. Despite an overlap in the major source proteins, many peptide sequences were different, i.e., species-specific. Remarkably, the data indicate that the human milk peptidome might be donor-specific as well.