[关键词]
[摘要]
酿酒酵母(Saccharomyces cerevisiae)和巴氏醋杆菌(Acetobacter pasteurianus)是白酒酿造过程中重要的发酵微生物,其对乙酸乙酯的生成有很大影响。本文采用酵母和醋酸菌同步接种和顺序接种方式,以酵母单独接种发酵作对照,研究了酿酒酵母与巴氏醋杆菌的相互作用及其对乙酸乙酯生成的影响。结果表明,采用同步接种方式,在发酵前期,醋酸菌对酵母的生长和代谢影响较小,酵母酒精发酵对醋酸菌的生长有抑制作用,混菌发酵乙酸乙酯的合成也受到一定抑制;在发酵后期,醋酸菌的生长和产酸将加快酵母衰亡,但有利于乙酸乙酯的合成,其最高达(595.72±5.01) mg/L,是酵母单菌发酵的10.1倍。采用顺序接种方式,在酵母发酵24 h后接种醋酸菌对酵母酒精发酵影响最大,其酒精度比对照低22.98±1.77%,乙酸乙酯含量都低于同步接种方式。此外,酵母代谢产生的某些物质会抑制醋酸菌合成乙酸乙酯,而当发酵体系中存在活酵母时,该抑制将解除。
[Key word]
[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.
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[基金项目]
广东省企业合作研发项目(X2SW-D8172300)