Buffalo milk increases viability and resistance of probiotic bacteria in dairy beverages under in vitro simulated gastrointestinal conditions

Probiotic dairy beverages prepared from buffalo and cow milks with different levels of whey (0, 25, and 50%) were evaluated for kinetic fermentation parameters, protein and fat contents, post-acidification profile, viability of Streptococcus thermophilus, Lactobacillus bulgaricus, and Lactobacillus acidophilus during 21 d of refrigerated storage, and resistance to in vitro gastrointestinal conditions. Progressive acidification that occurred during storage of all dairy products was reduced in the presence of whey. Lactic acid bacteria showed viable cell counts at the end of shelf life, with the highest values (7.33 to 8.83 log cfu/mL) detected in buffalo dairy products. Compared with fermented cow milk products, those made with buffalo milk showed better bacterial viability during in vitro simulated gastrointestinal digestion, which suggests a beneficial protective effect on human microbiome.