Study on the relationship between microbial community succession and physicochemical factors in the fermentation of rice-flavor Baijiu based on high-throughput and redundancy analysis techniques

Fermented grains are the main carrier of microbial fermentation and the direct source of Baijiu flavor substances, but so far, there are few studies on the changes in the fermented grains of rice-flavor Baijiu. This experiment systematically analyzed the correlation between microbial community succession and physicochemical factors in the fermentation process of two different types of rice (japonica: M and indica: H) fermented grains. The results showed that during the fermentation process, the changes in total acid, pH, starch, and total phenols of H and M were consistent. However, M and H showed different trends in terms of reducing sugar content and alcohol content. At the phylum level, both types of fermented grains had Firmicutes and Proteobacteria as the absolute dominant phyla. At the genus level, there was a slight difference in the dominant genera of M and H in the early stages, but the main genera in the later stages of fermentation were different. RDA analyses showed different correlations between dominant genera and physicochemical factors with some interesting results. The results of this study will provide a theoretical basis for the regulation of rice-flavor Baijiu fermentation.