Effects of Kuding Tea on the Succession and Assembly of the Fungal Community During Fermentation of Daqu

Abstract

Incorporating plant-based additives was a promising approach for modulating the microbial ecosystems of fermentation starters. This study investigated how adding Kuding tea (20% wt/wt) influenced the assembly and succession of fungal communities during Jiang-flavored Daqu production, compared to traditional wheat-based Daqu. Using amplicon sequencing of the ITS1 region and integrated measurements of endogenous factors, we analyzed community dynamics across a 40-day fermentation period. Results showed that tea addition significantly increased fungal diversity and altered succession trajectories. Community assembly shifted from stochastic towards deterministic processes, with homogeneous selection increasing from 0.47 in wheat-based Daqu to 0.62 in tea-added Daqu. Temporal species accumulation was stronger (STR exponent z: 0.565 vs. 0.436), while compositional turnover slowed (TDR slope w: −0.539 vs. −0.626). Random forest models revealed tea-specific fungal drivers and stronger correlations with endogenous factors (e.g., reducing sugar and moisture). We concluded that Kuding tea appears to function predominantly as an environmental filter that enhanced deterministic selection, stabilized community succession, and restructured the key microbial–physicochemical relationships, providing a potential strategy for steering Daqu fermentation.

Key findings

• ▸Kuding tea addition significantly increased fungal diversity and altered succession trajectories over the 40-day fermentation period.
• ▸Community assembly shifted towards deterministic processes with homogeneous selection increasing from 0.47 in wheat-based Daqu to 0.62 in tea-added Daqu.
• ▸Tea-specific fungal drivers were identified, and correlations with endogenous factors like reducing sugar and moisture were stronger in the tea-added samples.

Keywords

Identifiers

DOI

10.3390/fermentation12030136

Journal

Fermentation

Year

2026