Effect of refrigerated storage time on the viability of probiotic bacteria in fermented probiotic milk drinks

摘要

The viability of Lactobacillus acidophilus and Bifidobacterium lactis in fermented milks A, B and AB, containing respectively these strains separately and mixed, was studied over 21 days of storage at 5pC. Samples were analysed for titratable acidity and viable cell counts of probiotics. Milks A and AB showed post-acidification mainly due to the o-galactosidase activity of L. acidophilus. Generally, the viability of the probiotics decreased during storage, whereas, in some cases, the proteoletic activity of L. acidophilus resulted in a higher survival rate of the probiotics even with the adverse effects of low temperature and organic acids.