Survival of Bifidobacterium bifidum in cow- and camel-milk yogurts enriched with Cinnamomum verum and Allium sativum

AbstractThe effects of Allium sativum and Cinnamomum verum water extracts on the survival of Bifidobacterium bifidum during 21days of refrigerated storage and after simulated gastrointestinal digestion (SGD) were investigated. Two types of yogurt (cow- and camel-milk yogurts) were prepared in the presence of A. sativum or C. verum. The viable cell counts (VCC) of B. bifidum in fresh A. sativum- or C. verum-cow milk yogurt (1day) were higher (8.1×109cfu/ml and 6.6×109cfu/ml, respectively; p<0.05) than plain-yogurt (1.9×109cfu/ml). In contrast, B. bifidum VCC in fresh plain-camel milk yogurt was 1.99×109cfu/ml whereas the presence of A. sativum or C. verum in yogurt increased (p<0.05) VCC to 19.61×109cfu/ml and 25.55×109cfu/ml, respectively. The VCC of B. bifidum in both herbal-yogurts decreased (p<0.05) during refrigerated storage for both types of yogurt. The VCC of B. bifidum was ∼1.3×109cfu/ml in all fresh cow milk yogurts after 1h gastric digestion. Intestinal digestion (1h) increased VCC of B. bifidum in all fresh yogurts but not in 7day old yogurts (plain- and A. sativum-yogurts). However, prolonged digestion to another 1h in intestine reduced (p<0.05) VCC of B. bifidum in all fresh and storage yogurts. In contrast, all fresh camel milk yogurts showed VCC of B. bifidum ⩽1×109cfu/ml after SGD. Seven day old A. sativum – camel milk yogurt showed the lowest survival of B. bifidum after gastric digestion compared to plain- and C. verum-yogurt. The VCC reduced (p