Regulation of Ethyl Carbamate of Saccharomyces cerevisiae in Chinese Luzhou-Flavor Liquor Fermentation

The carcinogen ethyl carbamate (EC) in alcoholic beverages mainly comes from the spontaneous reaction of ethanol and urea, and urea is produced by the breakdown of arginine by arginase in Saccharomyces cerevisiae . Regulating activity of arginase and decreasing urea content are beneficial to reduce EC in liquor. In this study, Saccharomyces cerevisiae isolated from Daqu was fermented under a series of stress conditions to evaluate the content changes of EC and its precursors. Temperature and pH below 25 ° C and pH 4.0, ethanol concentration of 4–6% and a certain initial salt concentration could reduce arginine consumption and urea production by decreasing transcription level of arginase and increasing transcription level of urea carboxylase, and eventually lead to the reduction of EC. These methods will help to improve the strategy of EC control in Chinese liquor.