Microbial Diversity Analysis Of Jiaoke From Xilingol In Inner Mongolia

Jiaoke is a special fermented food in Inner Mongolia-one kind of the Mongolian creams that uses fat from fermented milk as raw material.It has rich nutrition and unique flavor.In this study,29 jiaoke samples from Xilingol were used as the research object.Lactic acid bacteria of Jiaoke was isolated,identified,stored by culture-dependent techniques and 16 S rRNA sequence analysis.It is the first time using electronic tongue technology and real-time single-molecule sequencing technology(SMRT)to determine the taste and analyse bacterial diversity of Jiaoke.The main findings of this article are as follows:(1)182 strains of lactic acid bacteria were isolated and identified by culture-dependent techniques,belonging to 14 species,5 genera of Lactococcus,Lactobacillus,Enterococcus,Streptococcus and Leuconostoc.Among them,Lac.lactis accounted for the highest proportion(46.70%),followed by L.plantarum,accounting for 12.64% of the total isolates.(2)Using electronic tongue technology to analyze the taste characteristics,four flavors in the Jiaoke samples varied greatly: the sweetness value ranged from-17.15 to 0.00,the bitterness value ranged from-5.33 to 1.72,and the sourness value ranged from-3.59 to 6.01,the salty taste value is between-1.77 and 5.42.(3)Using the PacBio SMRT sequencing technology to analyze the bacterial diversity of 14 samples from the metagenomic level,it was found that the bacteria in the Jiaoke was rich in composition.A total of 10 phylums,21 classes,34 orders,63 families,121 genus and 186 species was identified.The dominant phylums are Firmicutes,Proteobacteria and Bacteroidetes.The dominant genus,species are Lactococcus and Lac.lactis.This is consistent with the results of the traditional method.(4)?and?diversity analysis of bacterial in different flavor groups revealed that the samples may contain some unique LAB,but there are still a large number of key bacterial populations between the samples.