Preliminary technological and probiotic characterization of bifidobacteria isolated from breast milk for use in dairy products.

ZACARÍAS, M. F.; BINETTI, A. G.; LACO, M.; REINHEIMER, J. A.; VINDEROLA, G.

JOURNAL OF APPLIED MICROBIOLOGY

WILEY-BLACKWELL PUBLISHING, INC

Año: 2011 vol. 21 p. 548 - 555

1364-5072

Aim: To isolate and identify bacteria of interest for the food industry from human breast milk, and to determine their technological and probiotic potential for use in dairy products. Methods and Results: Six strains of Bifidobacterium animalis subsp. lactis were isolated out of 16 samples of breast milk. Two strains gradually lost their capacity to grow in laboratory media. Bifidobacteria were present in levels ranging from 1.4 to 2.8 log orders (cfu mL-1). Strains were resistant to frozen storage (-20ºC and -70ºC, 6 months) and to the refrigerated storage (5ºC, 4 weeks) in lactic acid-acidified milk (pH 4.5). Strains were also able to grow in skim milk with 0.05% (w/v) of yeast extract and they were resistant to spray-drying in 20% skim milk. Spray-dried cultures maintained a high number of viable cells when stored at 5ºC for 6 months and were resistant to the rehydration in water up to 50ºC. The oral administration of B. animalis subsp. lactis for 3, 6 or 10 consecutive days to mice was able to enhance the number of IgA+ cells in the lamina propria of the small and large intestine. Conclusions: Bifidobacteria isolated in this study showed technological and probiotic potential for their incorporation to dairy products, fermented or not. Significance and Impact of the Study:  This work contributes to the knowledge of the microflora of breast milk, its functionality and its technological capability for use in the dairy food industry for the development of new functional products. Key words: bifidobacteria, breast milk, dairy products, IgA, probiotics