摘要
乙醛是使啤酒产生硬纸板味、烂苹果味的主要来源,对啤酒品质有较大影响。本实验采用紫外诱变与高浓乙醛平板选育结合法,将筛选得到的菌株(共20株)与出发菌株进行低温发酵实验,然后利用气相色谱法测定菌株发酵液乙醛含量,并将其与出发菌株乙醛含量相比较。对具有较大乙醛降幅的菌株(共3株)进行乙醇脱氢酶活性的验证及稳定性实验,由此筛选出抗乙醛啤酒酵母菌株。该菌株可抵抗高浓度乙醛环境,从而快速还原代谢产生的乙醛,其乙醛含量为4.42 mg/L±0.14 mg/L,较出发菌株降低了71.13%;乙醇脱氢酶(ADH1、ADH3与ADH4)活性显著高于出发菌株(增幅为88.80%),且遗传稳定性表现良好。
Acetaldehyde is the main source of cardboard and rotten apple flavor in beer, which has a great influence on beer quality. In this study, acetaldehyde content in the fermenting liquid （low-temperature fermentation by starting strains and 20 experimental yeast strains screened by UV mutation and high-concentration acetaldehyde breeding method） was measured by GC. Then acetaldehyde content in fermenting liquid by experimental strains was compared with that by starting strains. And the activity of alcohol dehydrogenase and the stability test of the experimental strains （3 strains in total） with large decreasing amplitude of acetaldehyde content were carried out to select acetaldehyde-resistant yeast strains. The content of acetaldehyde of the final-selected beer yeast strains was 4.42±0.14 mg/L, 71.13 % lower than the starting strains; the activity of alcohol dehydrogenase （ADH1, ADH3 and ADH4 ） was significantly higher than the starting strains （increased by 88.80 % ）, and good genetic stability was expressed.
出处
《酿酒科技》
2016年第1期10-14,共5页
Liquor-Making Science & Technology
基金
国家国际科技合作专项项目(2014DFG31770)
关键词
微生物
乙醛
抗乙醛啤酒酵母
高浓乙醛法
乙醇脱氢酶
microbe
acetaldehyde
acetaldehyde-resistant beer yeast
high-concentration acetaldehyde method
alcohol dehydrogenase
