浓香型白酒发酵过程中氨基甲酸乙酯形成的关联因子探究

浓香型白酒中氨基甲酸乙酯（EC）影响其安全性。该实验考察了浓香型白酒发酵过程中酒醅EC含量分别与环境因子及微生物的相关性。结果表明，EC含量随着发酵时间的延长呈上升趋势，主要发生在发酵的中后期；pH与EC含量呈负相关，系数为0.9，而水分则与EC含量呈正相关，相关系数为0.83，温度和乙醇含量对EC的形成有一定的促进作用，相关系数分别为0.48和0.71。此外，发酵体系中乳杆菌属（Lactobacillus）和和酿酒酵母属（Saccharomyces）与EC含量的相关系数为0.97和0.96，两者的丰度越高，EC越容易积累；芽孢杆菌属（Bacillus）则对EC的合成起到反作用，与EC含量的相关系数为0.78。因此可在浓香型白酒的发酵期间人为调控pH值、水分含量及上调芽孢杆菌属在发酵微生物中的比例，达到降低EC含量的目的。

Correlation factors of ethyl carbamate formation during the fermentation of strong-flavor Baijiu

Ethyl carbamate (EC) in strong-flavor Baijiu (Chinese liquor) can affect its safety. The correlation between EC content in fermented grains during the fermentation of strong-flavor Baijiu and environmental factors and microorganisms was studied, respectively. The results showed that the EC content increased with the extension of fermentation time, which mainly occurred in the middle and later fermentation; The pH was negatively correlated with EC content with a coefficient of 0.9, while moisture was positively correlated with EC content with a coefficient of 0.83. Temperature and ethanol content had certain promotion effect on EC formation with a correlation coefficient of 0.48 and 0.71, respectively. In addition, the correlation coefficient between Lactobacillus, Saccharomyces and EC content in the fermentation system were 0.97 and 0.96, respectively. When the abundance of both was higher, the EC content was easier to accumulate. Bacillus had negative effect on EC synthesis, and the correlation coefficient with EC content was 0.78. Therefore, pH, water content and the proportion of Bacillus in fermentation microorganisms could be adjusted artificially to reduce EC content during the fermentation of strong-flavor Baijiu.