Synergism between ethanol and acidity drives microbial community succession during roasted sesame-flavor liquor solid-state fermentation

Abstract:

[Background] The assembly dynamics of microbial community and its environmental driving forces during liquor solid-state fermentation (SSF) is important for revealing the characteristics of brewing microbes. [Objective] The purpose of this study was to reveal microbial community succession and its environmental driving forces during roasted sesame-flavor liquor SSF. [Methods] The dominant genera and community structure transition were revealed by high-throughput sequencing. The distribution of metabolic pathways in prokaryotic microbial community during SSF was predicted by PICRUSt. The interpretation rate of physicochemical properties to microbial community composition was revealed by correlation analysis. The effect of physicochemical properties on community composition was verified by simulating fermentation under laboratory conditions. [Results] The roasted sesame-flavor liquor SSF process was divided into two stages: At stage I (0?5 d), ethanol and acidity reached the highest synthesis rate and consumption rate while Bacillus and Pichia were the most abundant prokaryotic/eukaryotic genus. Acidity was the key environmental driving force. At stage II (5?30 d), Lactobacillus and Saccharomyces were of highest abundance and ethanol was the key environmental driving force. The interpretation rate of physicochemical properties for microbe’s distribution during SSF was 68.27%. Ethanol and acidity accounted for 13.76% and 4.43% respectively while the combination of ethanol and acidity accounted for 23.17% and had significant synergism on driving community succession. [Conclusion] The study revealed microbial community succession and its environmental driving force, which could help to control the liquor SSF processes effectively.