新疆不同地区开菲尔粒中乳酸菌的分离鉴定及筛选

Isolation,Identification,and selection of Lactic acid bacteria from Kefir grains in different Xinjiang area

以新疆不同地区采集的7种开菲尔粒作为分离源,通过形态观察、16Sr DNA序列分析,分离出27株乳酸菌,其中有22株开菲尔乳杆菌,3株肠膜明串珠菌和2株假肠膜明串珠菌。对27株菌通过初级筛选:酸度、持水率、感官评价,筛选出10株酸度适宜、持水率高并且风味及组织状态好、感官评价高的乳酸菌。通过次级筛选:后酸化能力、产乙醛和双乙酰能力、冷藏期间活菌数,最终筛选得到4株性能优良的乳酸菌,包括3株开菲尔乳杆菌NR2、XR3、TXR4和1株肠膜明串珠菌XR1。因此这4株菌可作为乳品工业复合菌种发酵剂的优良配伍菌株使用,可为酸乳风味提供更多的选择。

In order to obtain good Lactic acid bacteria for fermented milk, the study collected 7 kinf of kefir grains in xinjiang different area as sources of separation, and isolated,identified 22 strains of 5 Lactobacillus kefiri, 3 strains of Leuconostoc mesenteroides and 2 strains of Leuconostoc pseudomesenteroides with the method of the morphological observation and 16 s rDNA sequence analysis. 10 strains of Lactic acid bacteria have good performance through primary screening：acid producing ability, water retention rate and sensory evaluation. 4 excellent performance of Lactic acid bacteria strains were selected through secondary screening, including 3 strains of LactobaciUus kefiri NR2, XR3, TXR4 and 1 strain of Leuconostoc mesenteroides XR1. Therefore, these four strains can be used as the excellent compatibility strains of the compound starter of dairy industry, which can provide more choices for the flavor of fermented milk.