洋河浓香型白酒发酵过程酒醅微生物群落结构解析及其与有机酸合成的相关性

Microbial community of fermented grains and its correlation with organic acids biosynthesis during Yanghe strong-aroma liquor manufacturing process

摘要:

[目的]解析江苏洋河酒厂浓香型白酒窖内发酵过程酒醅微生物群落结构，建立酒醅微生物与主要有机酸合成的关联性。[方法]通过宏基因组测序获得白酒发酵过程中微生物群落结构变化规律，利用主成分分析和偏最小二乘回归分析寻找酒醅中影响主要有机酸合成的关键微生物。[结果]根据微生物组成结构变化和有机酸合成变化规律，可将白酒窖内发酵分为两个时期（0-14 d和15-60 d）。其中窖内发酵0-15 d与主要有机酸合成相关的微生物数量显著高于15-60 d的。窖内发酵过程与主要有机酸合成相关的微生物包括7个菌属，分别为乳杆菌属（Lactobacillus）、葡萄球菌属（Staphylococcus）、酵母属（Saccharomyces）、Naumovozyma、伊萨酵母属（Issatchenkia）、嗜冷芽孢杆菌属（Psychrobacillus）和根霉属（Rhizopus）。[结论]本研究识别了白酒窖内发酵过程中与主要有机酸合成相关的核心和关键微生物，可为阐明白酒窖内发酵产酸机理和保障白酒品质的稳定性奠定研究基础和理论依据。

关键词:浓香型白酒;微生物组成;有机酸;偏最小二乘回归;核心微生物

Abstract:

[Objective] To analyze the microbial community of fermented grains during Yanghe strong-aroma liquor fermentation process, and to establish the correlation between the microorganisms and the biosynthesis of main organic acids.[Methods] The microbial community of fermented grains was analyzed by metagenome sequencing. Principal component analysis and partial least-squares regression analysis were used to find the key microorganisms correlated with the biosynthesis of main organic acids.[Results] The fermentation process can be divided into two periods (0-14 d and 15-60 d), according to the change of microbial composition and the biosynthesis of organic acids. The number of microbes significantly correlated with the biosynthesis of main organic acids from 0 to 15 d was significantly higher than that from 15 d to 60 d. The core microorganisms involved in the biosynthesis of major organic acids were characterized belonging to seven genera:Lactobacillus, Staphylococcus, Saccharomyces, Naumovozyma, Issatchenkia, Psychrobacillus and Rhizopus.[Conclusion] The core and key microorganisms involved in the biosynthesis of major organic acids during Chinese strong-aroma liquor fermentation process were identified. The results may laid the practical foundation and theoretical basis for elucidating the mechanism of acid production in Chinese strong-aroma liquor fermentation process and guarantee of the quality control of liquor.

Key words:Chinese strong-aroma liquor;microbial community;organic acids;partial least squares regression;core microorganisms