Green Tea Altered Temporal Dynamics and Environmental Adaptation of Microbial Communities in Moutai-Flavored Daqu Fermentation

Abstract

This study investigated the effects of green tea addition on microbial community dynamics during Daqu fermentation. We prepared four types of Daqu, including varying percentages of tea, and collected samples at six time points. Using 16S rRNA and ITS sequencing, we analyzed bacterial and fungal communities, Species-Time relationships model revealing significant species richness increases over time (P < 0.001), with intercept values rising from 443.13 in the original Daqu to 466.58 in the 30% tea-added Daqu. Time-decay relationships model indicated slower community turnover rates across all Daqu treatments, with no significant acceleration due to tea. Notably, the introduction of tea extended the response window for both bacterial (up to Day 15) and fungal shifts (as early as Day 6). Assembly processes were predominantly stochastic, but deterministic influences intensified with higher tea content. Tea altered the impact of endogenous factors on β-diversity, particularly reducing the phylogenetic conservatism of microbial communities. These findings highlight the significant role of tea in reshaping microbial structure and adaptability, suggesting that ingredient modifications can enhance microbial diversity and influence fermentation dynamics in Daqu production.

Keywords: Green tea addition, community assembly, environmental adaptation, endogenous factor, phylogenetic conservatism