Abstract: Daqu is a traditional natural fermentation starter in China. It plays an important role in the production and flavor formation of traditional vinegar due to its complex microbial communities, substances and enzymes. Intensive studies have been carried out to reveal the functional microbial community, enzymes and flavor substances in vinegar Daqu. Here, the functional microbial community and quality characterization of vinegar Daqu, the factors influencing vinegar Daqu quality and the relationship between Daqu quality and vinegar quality, as well as the current measures used to improve Daqu quality are reviewed. We expect that this review will provide valuable information for the production and quality improvement of vinegar Daqu.

Key words: vinegar, Daqu, microbial community, quality, bioaugmentation