The Selection Of Fine Wine-making Microbes In Xinjiang

The paper based on the collected vineyard soil, grapes, leaves, juice and wine from area A、B and C, In order to select fine wine-making microbes and yeasts, used the combined means of biotechnology and traditional fermentation engineering, and explored the factors which can influence yeast acid production ability, Analyzed the microbial diversity of the samples by high-throughput sequencing of Illumina MiSeq, The author used the selected yeasts made wine and done quality analysis, and realized the promotion of Xinjiang-featured wine quality finally. The main results are as follows:(1)High-throughput sequencing indicated that on the condition of 97% similarity, the author classified 4597 fungi OTU. The dominant fungi in the soil were Ascomycota, Sordariales and Tetracladium; in the grapes and wine was Scleroderma, in the leaves were Aureobasidium and Pleosporaceae. Among the 23458 bacterial OTU, The dominant bacterial in the soil were Arthrobacter, Kaistobacter and Skermanella; in the grapes and leaves were Pseudomonas, Adhaeribacter and Sphingomonas; in the juice and wine was Oenococcus.(2)Strains of samples in Xinjiang region are identified by 26 S rDNA,16 S rDNA, It showed that 31 Saccharomyces cerevisiae and 9 bacterium were isolated. The 12 Saccharomyces cerevisiae and 3 Malolactic Bacteria with fine wine-making ability were screened after fermantation performance test, malic acid decomposition test and tolerance test.(3)The formula for selecting high acid brewing yeast culture medium were: PDA basal medium and 0.01% bromocresol green, 115℃ sterilizing 20 minutes. Via medium selection and fermentation test, a high acid brewing yeast Y6 was obtained, which is 2.00 g/L higher than the control strain 71 B. a fermentation degree controllable wine yeast Y2 was obtained, which can control alcohol at 12.00% Vol. By single factor experiments tested their influence on yeast acid productivity, the conclusion was drawn that the juice initial acidity should be 6.50 g/L, fermentation temperature 20.00℃,yeast inoculation quantity 108 cfu/mL. By response surface optimization tested, the two degree polynomial regression equation was γ=6.88+0.36*A+0.45*B+0.20*C+0.068*AB+0.37*AC-0.068*BC+0.45*A2-0.13*B2+0.22*C2, During the experiment, predicted the fermentation conditions of acid production were the grape juice initial acidity 6.70 g/L, fermentation temperature 20.35℃, inoculation quantity 109 cfu/mL, the response predictive value was 1.7664 g/L.(4)Subject for screening the high acid brewing yeast Y6 and fermentation degree controllable wine yeast Y2 brewing production test, The results showed that the physical and chemical indexes accord with Chinese wine standard after fermentation, mono-phenol and flavor substances were in accordance with the 71 B, Electronic Tougue analysed the sourness of NO.1 wine was highest. what’s more, acid production of Y6 was 2.39 g/L higher than 71 B, and Y2 can control alcohol at 12.00% Vol. Those indicated that Y6 and Y2 were target strains for the test.