Comparison of Acetic Acid Production Characteristics of Different Grains in Baijiu Brewing

To investigate the differences in the production of acetic acid and ethyl acetate during Baijiu production using various grain raw materials, including sorghum, glutinous sorghum, rice, glutinous rice, wheat, and corn, with medium-high temperature Daqu as the fermentation agent. The results indicate that bacteria were the primary microorganisms responsible for acetic acid production, and yeasts were predominantly responsible for ethyl acetate production. The contents of acetic acid and ethyl acetate were the highest in glutinous sorghum fermented grains, with specific contents of 1.45g /kg and 1.76g /kg, respectively, while the acetic acid was the lowest in rice and glutinous rice fermented grains. Furthermore, microbial community result showed that Bacilli and Pichia were positively correlated with the production of acetic acid and ethyl acetate, significantly, so Bacilli and Pichia are the key microorganisms in Baijiu. This study provides a theoretical basis for selecting raw materials to control acetic acid and ethyl acetate content in strong-flavor Baijiu and offers new approaches for improving Baijiu quality.