益生菌混合菌种在发酵豆乳中的优化

采用益生菌混合物AST和TLB分别在42℃进行豆乳的发酵,在发酵豆乳的发酵和贮存过程中(4℃下28d),观察pH值和活菌数的变化情况。在AST益生菌混合物(嗜酸性乳杆菌,双歧杆菌和嗜热链球菌)的培育下,42℃下发酵时间减少到8h。但嗜酸性乳杆菌在冷藏的过程中生存状态较差,其活菌数在冷藏后一周后未达到标准。将豆乳在42℃下用TLB益生菌(嗜热链球菌,保加利亚乳杆菌和动物双歧杆菌乳酸亚种Bb12)进行发酵,结果发酵时间缩短到4h,双歧杆菌活菌数目的对数增加了约一半,而且经过28d的冷藏,细菌数仍然维持在107 CFU/mL以上。

Optimizing Fermentation of Soymilk with Combination of Probiotic Bacteria

The objective of this study is to produce a probiotic fermented soymilk with the aim of shortening the fermentation time.For this,soymilk was fermented with probiotic culture AST and yoghurt culture TLB at 42 ℃,during the fermentation and storage of the fermented soymilk(28 days at 4 ℃,the changes in pH-value and viable cells count were observed.Fermentation time significantly reduces to 8 h at 42 ℃ with AST culture(Lactobacillus acidophilus,Bifidobacterium spp.,and Streptococcus thermophilus).However,Lactobacillus acidophilus survived poorly during cold storage and the viable cells count was under the probiotic minimum as soon as after the first week of storage.Soymilk was fermented at 42 ℃ with TLB culture(Streptococcus thermophilus,Lactobacillus bulgaricus,Bifidobacterium animalis subsp.lactis Bb12).Consequently,the fermentation time was shortened to 4 hours whereby the viable cells count of bifidobacteria increased during fermentation for the half of the logarithm scale approximately.During 28 days of cold storage,bacterial count remained over 107 cfu/mL.