Study On Characteristics Of Low-yielding Ethyl Carbamate And Biogenic Amines Microbes In Wine

This study aimed at entire technology update of Xinjiang region, using modern high-tech methods on biotechnology and fermentation engineering, focucing on breed, brew and monitor, low ethyl carbamate and biogenic amine Saccharomyces cerevisiae, and lactobacillus have been screened. The main research conclusions are as follows:(1) Established methods of EC, urea, amino acids and BA. EC detection method repeatability RSD = 11.4%, RSD = 17.7%, reproducibility recovery was 89.43; BA detection method repeatability RSD = 5.11%, recovery rate is 97.45; Urea detection method repeatability RSD = 3.0%, repeatability RSD = 4.1%, recovery rate is 97.47%; Amino acid detection method repeatability RSD = 2.33%, repeatability RSD = 3.14%, recovery rate of 88.75. The research indicates suitable the relevant analysis requirement of wine for good results of linearity, precision, and recovery rate.(2) Strains of samples in Xinjiang region are screened and identified. It shows representativeness, pertinence and illustration on the selected microbial source. 50 yeasts and 20 bacteria strains are founded and separated. 13 S.cerevisiae and 6 lactobacillus are finally screened after WL, TTC, malic acid decomposition test and tolerance test.(3) Using the Optimum strain in Xinjiang region, the content of EC, urea, amino acids and BA are detected. It indicate that amino acid express exponential growth relationship with EC respectively during the fermentation, which represent directly affection of the content of EC in wine; S.cerevisiae strain Y44, After alcoholic fermentation EC content in the fermented liquid of only 1.51μg/L; Oenococcus oeni LB, and L66 are the best in low EC during the fermentation process; the existence of amine producing lactic acid bacteria plays an important role in increasing content of BA. In terms of the capacity of producing amine, Lactobacillus plantarum has great influence on the content of BA, the Oenococcus oeni LB and L66 strains are excellent in low BA in the study.(4) The specific genes of low EC and BA are researched by real-time fluorescent PCR technology, The results show that the activity of yeast CAR1 gene is decreased after the increasing trend, different yeast CAR1 significant differences relative to express genes, screening of arginine low enzyme activity of saccharomyces cerevisiae can effectively reduce the content of ethyl carbamate in the wine.(5) Using saccharomyces cerevisiae were studied industrial test the results showed that laboratory screening of saccharomyces cerevisiae Y44 has good characteristics and production performance, and it is the low yield of ethyl carbamate fine wine yeast strains.