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The aim of this study was to evaluate the influence of the growth of lipolytic bacteria in raw goat milk stored under refrigeration for different periods on quality parameters of goat milk powder during its shelf life. Fresh goat milk (100L) was collected after milking, divided into 3 identical fractions, and stored at 4°C for 1, 3, and 5d. On d 1, 3, and 5, one sample (1L) was collected and used for microbiological and chemical analysis, and the remaining fraction (almost 30L) was spray dried and stored at 25°C. Milk powder was submitted to microbiological, chemical, and sensory analysis immediately after production, and on d 60, 120, and 180. Lipolytic psychrotrophic counts and total free fatty acid content did not increase in raw milk during storage. However, peroxide value, caprylic and capric acid concentrations, and total free fatty acid content of milk powder increased during 180d of storage, with higher levels found in milk powder manufactured with raw milk stored for 5d. Capric odor and rancid flavors increased in milk powder during storage, regardless the of storage of raw milk for 1, 3, or 5d. Heat treatments used during powder processing destroyed lipolytic psychrotrophic bacteria, but did not prevent lipolysis in milk powder. Results of this trial indicate that the storage of raw goat milk at 4°C should not exceed 3d to preserve the quality of goat milk powder during its shelf life of 180d.

In this study, physical characteristics of goat milk powder produced with the addition of soy lecithin at levels of 0 (control), 0.4, 0.8 and 1.0 g lecithin ⁄ 100 g of total solids in concentrated milk before the spray drying process were investigated. Goat milk was pasteurised, concentrated at 40% of total solids, spray dried and packed in plastic bags under vaccum conditions. Lecithin addition decreased the wetting time of milk powders, although no influence was observed on dispersibility, water sorption, water activity and particle size distribution of the powders. Powders with higher levels of lecithin showed significantly lower brightness, with a greater intensity of yellow colour. It was concluded that lecithin addition before spray drying process at the minimal proportion in concentrated milk of 0.4 g lecithin ⁄ 100 g of total solids in concentrated milk is useful for achieving more rapid wetting time of goat milk powder.

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resumoForam avaliados diferentes períodos (0, 3 e 6 dias) e 2 temperaturas (4° e 10 °C) no armazenamento do leite de cabra cru e sua influência sobre a qualidade e vida útil do produto pasteurizado. Nos períodos descritos de armazenamento, procedeu-se à pasteurização lenta do leite (65 °C/30 min), sendo o produto processado armazenado a 10 °C por mais 6 dias. As amostras do leite cru foram caracterizadas imediatamente após a ordenha e após o 3° e 6° dias de armazenagem. O leite pasteurizado foi caracterizado imediatamente após a pasteurização e após o 3º e 6º dias de armazenagem a 10 °C. Foram realizadas as seguintes análises: contagens de microrganismos mesófilos, psicrotróficos totais, lipolíticos e proteolíticos, coliformes totais e fecais e físico-químicas: acidez, gordura e ácidos graxos livres (AGL). As populações de microrganismos no leite cru tiveram maior desenvolvimento na temperatura de 10 °C do que a 4 °C. A acidez manteve-se dentro do aceitável na armazenagem a 4 °C por 6 dias, mas não a 10 °C. Foi observado decréscimo significativo (p < 0,05) no teor de gordura do leite cru durante o armazenamento em ambas as temperaturas e o aumento gradativo da quantidade de ácidos graxos livres (AGL). A pasteurização foi eficiente na redução microbiana, sendo que os microrganismos psicrotróficos lipolíticos e proteolíticos não foram mais detectados após o processo. Contudo, as alterações ocorridas durante o período de estocagem do leite cru influenciaram as características físico-químicas do leite pasteurizado. Durante o armazenamento do leite pasteurizado, os valores de acidez e teor de gordura permaneceram estáveis, enquanto a quantidade de AGL continuou aumentando significativamente. Concluiu-se que o leite de cabra cru pode ser armazenado por até 3 dias a 4 °C, para o produto pasteurizado ter uma vida útil de 6 dias. A temperatura 10 °C não deve ser utilizada na conservação do leite cru. palavras-chave: qualidade de leite, refrigeração do leite, microbiologia do leite, lipólise, caprinos. abstract QUALITY OF IN NATURA GOAT MILK AND PASTEURIZED PRODUCT STORED FOR DIFFERENT PERIODS. Different periods (0, 3and 6 days) and 2 temperatures (4 °C and 10 °C) of raw goat's milk storage and its impact on pasteurized product quality and shelf life were evaluated. In the described periods, slow pasteurization (65 °C/30 min) was carried out and the pasteurized product was stored at 10 °C for 6 days. Raw milk samples were characterized after milk handling and after 3 and 6 days of storage. Pasteurized milk was evaluated immediately after heat treatment and after 3 and 6 days of storage at 10 °C. The counting of mesophiles, total, lipolytic and proteolytic psichotrophic bacteria, total and fecal coliforms, acidity, fat and free fatty acid (FFA) contents were determined. The microorganisms' populations had a higher growth at 10 °C than 4 °C. Acidity remained in acceptable levels during storage at 4 °C for 6 days, but not at 10 °C. There was a significant decrease (p < 0.05) in raw milk fat content during storage in both tem...

ABSTRACT: The objective of this study was to analyze the potential of the jabuticaba peel flour (JPF) as an ingredient in whole-grain bread. Pan bread formulations with different concentrations of jabuticaba peel flour were made: 0% (T0), 5% (T1), 10% (T2), and 15% (T3). Proximate composition, pH, water activity, color, phenolic compounds and antioxidant activity of bread were determined. The addition of JPF to the bread formulations led to a reduction of carbohydrate levels (51.14 to 46.55 g 100 g-1), lipids (4.79 to 3.35 g 100 g-1) and an increase in moisture (31.06 to 37.31 g 100 g-1) and ash (0.22 to 0.35 g 100 g-1). The fiber content increased up to three times, and the phenolic compounds up to seven times, thus increasing the antioxidant activity of the JPF-based bread when compared to the control. Bread made with the addition of JPF presented lower L* values (46.72 to 36.07) and higher a* values (3.10 to 9.07) compared to the control. Therefore, jabuticaba peel flour can be considered a potential ingredient for addition to whole-grain pan bread with desirable nutritional and functional characteristics.

Fillet Spoto, pelo apoio e ensinamentos; À Prof. Dra. Ivanete Susin, pelo apoio, carinho e pela matéria-prima utilizada neste trabalho. Ao Prof. Dr. Carlos Tadeu dos Santos Dias, pelo auxílio durante a análise estatística; Aos funcionários do Capril da ESALQ/USP, pela assistência e amizade; Às funcionárias do Depto. de Agroindústria, Alimentos e Nutrição Cleomar Maria de Carvalho e Denise de Almeida Leme Baptista, pelo auxílio e amizade; Aos funcionários do Depto. de Agroindústria, Alimentos e Nutrição Luiz Carlos Rodrigues e Rubens César Pereira, pelo auxílio em informática; À Prof. Dra. Maria Isabel Franchi Vasconcelos Gomes (Bel), da UNESP-Botucatu, pela fundamental colaboração para minha formação profissional e principalmente amizade ao longo dos últimos anos; Aos provadores do leite de cabra pasteurizado, pela compreensão e dedicação ao trabalho; Às amigas Aline Brigato, Naiane Sangaletti, Fabiana Jordão, Cristiane Pires, Mônica Félix e Ana Cláudia Rossi pela amizade, companheirismo, auxílio, ensinamentos, conselhos e alegrias.