Analysis Of Microbial Diversity And Metabolic Characteristics Of Jiaoke In Inner Mongolia

Jiaoke is a kind of cream product among Mongols traditional dairy products.It has strong milk flavor,rich nutrition,and is rich in a variety of high-quality proteins,vitamins and minerals.However,it is still in the stage of small workshop production and home production,with large quality differences,which limits the standardized production and industrial development of Jiaoke.In this study,nine samples of jiaoke were collected from two regions of Xilingol League and Hulunbeier City.The pure culture technology was used to isolate and identify the lactic acid bacteria.Metagenomics,metabonomics and electronic nose technology were used to analyze the microbial community structure,metabolite composition and flavor quality of jiaoke,and analyze the impact of microbial composition on jiaoke quality differences,to provide a theoretical basis for the standardized production and quality control of jiaoke.The main research content is as follows:(1)A total of 90 strains of lactic acid bacteria were isolated and identified from jiaoke samples using pure culture technology,belonging to 4 genera and 13 species.Among them,the dominant bacterial species in the jiaoke samples from both regions are Lactococcus lactis.(2)Based on metagenomics,the microbial diversity of jiaoke was analyzed,and 165 strains were identified.The dominant strain in jiaoke is Lactococcus lactis,which is consistent with the results of strain isolation and identification.In addition,the sequencing results were analyzed through microbial diversity research,and the results showed that the microbial diversity levels of the samples from the two regions were similar,but there were significant differences in microbial composition.(3)Using non targeted metabolomics,a total of 31214 metabolic substances were detected in the composition of jiaoke in two regions.There were significant differences in the composition of jiaoke metabolites between the two regions,with 64 different metabolites present,mainly including amino acids and peptides,carbohydrate and carbohydrate complexes,lipids and lipid molecules.It is speculated that these metabolites are related to pathways such as aminoacyl-t RNA biosynthesis,arginine biosynthesis,and lysine biosynthesis.And it was found that Lactococcus lactis showed a significant positive correlation with glutamine alanine,arginine proline,and N-acetyl-L-phenylalanine,indicating that dominant bacteria are involved in the synthesis of key metabolites.(4)By using electronic nose technology to analyze the flavor characteristics of jiaoke,it was found that the response values of the electronic nose sensors W1 W,W5S,and W1 S were relatively high,indicating that the content of flavor substances such as sulfides,nitrogen oxides,and alkanes in jiaoke was relatively rich.In summary,the flavor characteristics and metabolic substances of jiaoke are closely related to the microbial composition,indicating that microorganisms have a significant impact on the quality of jiaoke.This study utilized a combination of metagenomics and metabolomics to analyze the microbial composition and quality characteristics of jiaoke,in order to provide a theoretical basis for the standardized production of jiaoke.