摘要
Medium-high temperature Daqu is primarily controlled during the production process by regulating environmental temperature and humidity to manage fermentation.In this study,we analyzed the mechanism of regulating the temperature and humidity change rate during the warming period to affect the structure and function of the Daqu microbiota.The results of the study showed that Daqu fermentation occurs in two stages:the temperature increase period(P1),and the combined high temperature and temperature cooling period(P2),with rapid changes in the microbial community structure at the P1 stage,but not significant at the P2 stage.The microbial community structure of Daqu in P1 stage was significantly correlated with environmental factors.Under different rates of temperature and humidity changes,the succession of microbial communities,the breadth of microbial ecological niches along environmental gradients,and the patterns of community assembly differ,resulting in differences in the microbial community structure in Daqu.The slower rate of temperature and humidity change endows Daqu microorganisms with higher species diversity,and makes the abundance of enzymes related to carbohydrate decomposition and volatile metabolite formation in Daqu microorganisms higher,further resulting in a higher content of flavor substances(e.g.Ester content:20 mg/kg at slow rate,4 mg/kg at fast rate).These findings will facilitate more accurate regulation of Daqu production by controlling the rate of temperature and humidity changes during the temperature increase period.
基金
supported by the Innovation Fund of Postgraduate,Luzhou Laojiao Co.,Ltd.(No.LJCX2023-4)
the Project of the Science and Technology Department of Sichuan Province(No.2024ZHCG0094).
