Application of mixed-culture with Lactobacillus brevis and Saccharomyces cerevisiae to Chinese yellow rice wine brewing for ethyl carbamate regulation

Co-culturing two or more species has recently been used in fermenting foods for product flavor or safety control. Ethyl carbamate (EC) is a potential carcinogenic compound presented in Chinese yellow rice wine which can be reduced by fermentation starters modification. In this work, the effect of Lactobacillus brevis (L. brevis) on EC in yellow rice wine fermentation with Saccharomyces cerevisiae (S. cerevisiae) was studied and an optimal mixed-culture fermentation method was constructed according to comparative analyses of EC concentration and fundamental quality. EC concentration could be further reduced by 68.4% at most through adding 108 cfu/L L. brevis during S. cerevisiae fermentation. L. brevis also had beneficial influence on hedonic quality of yellow rice wine. Meanwhile, the effect of gallic acid on EC formation in this mixed-culture fermentation system was elucidated. Unfortunately, the coexistence of gallic acid and L. brevis attenuated their inhibitory effect on EC formation.