Abstract:Saccharomyces cerevisiae and Acetobacter pasteurianus were important fermentation microorganisms in the production of liquor brewing, which had a significant effect on the generation of ethyl acetate. The interaction of S.cerevisiae and A.pasteurianus and its effect on the generation of ethyl acetate were investigated in this paper by using synchronized and sequential modes, and taking the S.cerevisiae inoculation as a control. The results indicated that A.pasteurianus had little impact on the growth and metabolism of S.cerevisiae in the early fermentation stage by using synchronized inoculation, and the S.cerevisiae alcoholic fermentation inhabited the growth of A.pasteurianus and the synthesis of ethyl acetate in the mixed fermentation. In the late fermentation stage, the growth and acid production of A.pasteurianus accelerated the decline of S.cerevisiae and the synthesis of ethyl acetate. The highest content of ethyl acetate was 595.72±5.01 mg/L, which was 10.1 times than that of S.cerevisiae fermentation. The A.pasteurianus, inoculated with yeast for 24 h, had the greatest impact on S.cerevisiae alcoholic fermentation by using sequential inoculation .The alcohol content was lower 22.98±1.77% than that of the control, and the content of ethyl acetate in sequential inoculation mode was lower than that in synchronous inoculation mode. In addition, some substances produced by S.cerevisiae metabolism inhibited the synthesis of ethyl acetate by A.pasteurianus, which could be relieved with the presence of living S.cerevisiae in fermentation system.
