发酵型核桃乳生产专用链球菌的选育

从发酵面包、白芥丝、泡菜、酱黄瓜中,分离到14株链球菌,经过产酸特性测试,菌株HsS5、HsS6、HsS8、HsS9适合核桃乳发酵。通过菌落形态、菌体形态、生化特性和16SrRNA基因序列分析,确定4株链球菌均为嗜热链球菌。采用菌株HsS5、HsS6、HsS8、HsS9分别与实验室保存的嗜酸乳杆菌LA共同发酵,发酵型核桃乳感官评价分别为96,91,93,86分;且4个发酵核桃乳中9种氨基酸都有不同程度的提高,其中HsS5氨基酸含量增幅最大,由0.67%增加到1.75%。综上所述,菌株HsS5适宜核桃乳的发酵生产。

Screening of streptococcus used for the fermented walnut mink drink

In this study, 14 Streptococcus strains were isolated from sourdough bread, white silk mustard, pickles and cucumber sauce. Among those strains, four strains marked as HsS5, HsS6, HsS8, HsS9 could be used for the fermentation of the walnut milk after acid feature test, and they were identified as Streptococcus thermophilus through their morphologic, physiological biochemical characteristics and 16S rRNA gene sequence. The scores of sensory evaluation of these fermented walnut milks produced by HsS5, HsS6, HsS8, HsS9 with Lactobacillus acidophilus LA were 96, 91, 93, 86, respectively. Moreover, the contents of nine kinds of amino acid were found increased at different degrees in these four kinds fermented walnut milk, especially in HsS5, increased most significantly from 0.67% to 1.75%. According to the above results, strain HsS5 was more valuable for fermented walnut milk production than other strains.