Comparison of Fermentation Properties and Quality Changes during Cold Storage of Goat’s Milk Fermented by Lactobacillus acidophilus and Bifidobacterium

In this study,Lactobacillus acidophilus and Bifidobacterium were compared for proliferation and acid-producing properties in fresh goat’s milk as well as proteolytic activity and survival rate during cold storage of fermented goat’s milk.The results showed that during the fermentation period,compared with Bifidobacterium,Lactobacillus acidophilus revealed better acid-producing characteristics and proteolytic activity(P 0.05),and consistent change trend in proliferation.During the subsequent cold storage,the difference in acid-producing capacity between both probiotic strains became less or even disappeared until the 11th day.The proteolytic activity of Lactobacillus acidophilus was significantly higher than that of Bifidobacterium(P 0.05).The high-level activities of Bifidobacterium and Lactobacillus acidophilus were preserved with no significance during 21 days of storage(P 0.05).Between the storage days 21 and 26,the activities exhibited a distinct decrease of approximately 80.8% and 88.4% in survival rate(P 0.05).In a word,both probiotics have similar proliferation and fermentation performance in goat’s milk.However,Lactobacillus acidophilus is better than Bifidobacterium in acidproducing characteristics,survival rate and proteolytic activity.