Correlation Analysis between Microecological Structure and Fermentation Characteristics of Different Aroma Types of Daqu

Physicochemical analysis, headspace-solid phase microextraction (HS-SPME) combined with gas chromatography-mass spectrometry (GC-MS) and high-throughput sequencing were used to investigate the potential relationship between the microecology of different flavor types of Daqu and their physicochemical indexes and characteristic flavor compounds. The results showed that the highest saccharification power and fermentation power were found in Fenflavor Daqu, the highest esterification power and starch content in Luzhou-flavor Daqu, and the highest acidity were found in Maotai-flavor Daqu. In the three types of Daqu, the dominant bacterial genera were Saccharopolyspora, Weissella and Bacillus, and the dominant fungal genera were Saccharomycopsis, Aspergillus and Thermomyces. Correlation analysis showed that Bacillus was positively correlated with saccharification power, liquefaction power, fermentation power, ethyl caprate and phenyl ethanol. Thermomyces was positively correlated with ethyl caproate, isoamyl alcohol, ethyl lactate, acetic acid and ligustrazine.