Abstract: In order to explore the effect of hot air drying on the fungal communities in Daqu during storage, qPCR and high-throughput sequencing were used to analyze and compare the fungal community structures in Daqu with different treatments. The results showed that the number of 18S rRNA gene copies of fungi in all Daqu samples was between 1 × 1011 and 4.5 × 1011 copies/g, and the maximum number of copies of ZR3 was 4.5 × 1011 copies/g. Thermoascu spp., Rhizomucor spp., Aspergillus spp. and Candida spp. were the dominant fungi in all tested samples. Among these, Thermoascus spp. was the most predominant and it remained predominant during storage in Daqu storehouse. Compared with the storehouse environment, the laboratory storage environment was more conducive to the growth of Aspergillus spp.. Candida spp. grew better in dried Daqu. Besides, higher diversity indexes were observed in Daqu RG3 with hot air drying and subsequent laboratory storage for 2 months, as well as significant differences in the fungal communities, especially Wallemia spp., Byssochlamys spp., Penicillium spp. and Aspergillus spp.. Furthermore, principal component analysis (PCA) showed that the drop point of Daqu RG3 was relatively far away from other samples. Hence, it is worth further study to provide guidance for the industrial application of hot air drying on Daqu.

Key words: Daqu, hot air drying, storage method, fungal community