Screening Of High-efficient Yeasts In Green Plum Wine And Study On Fermentation Technology Of Compound Yeasts

The research of this subject takes the wild green plum from libo county,guizhou as the raw material,and the fermented green plum wine as the object.The brewing of green plum wine requires not only the high-quality raw materials,but also the excellent yeast species as the brewing basis.In view of the current problems in the production process of green plum wine,it is easy to appear the problems of poor fruit aroma,rough taste,excessive acidity,turbidity and discoloration,which leads to the cold market response to green plum wine.The most common green plum wine on the market is soaked green plum wine,which seriously hinders the development of green plum wine market.To this end,combining with the actual production of the enterprise,this paper took the green plum fruits and soil of wild merlin in libo county,guizhou province,maotai-flavor fermented grains and finished qu and five kinds of qu sold in the local market as separate sources to screen high-performance yeast.The fermentation broth of green plum wine with good fermentation on the production was used as the separation source to screen out the strengthened yeast.Then on the basis of the original green plum wine brewing process,the compound fermentation was carried out with the selected high performance yeast and the strengthened yeast,and the optimization of the compound fermentation process was studied.In this optimization of production process to guide the enterprise industrialization production of a strong aroma,taste coordination and suitable for the development of libo tourism characteristic green plum fruit wine.The main contents and conclusions of this paper are as follows:?1?400 strains of yeast were isolated from the green plum fruits and soil of wild merlin in libo county,the fifth round of maoxian-type fermented grains and finished koji,and five kinds of koji sold in the local market.100 strains of yeast were isolated from the fermentation broth with good fermentation in the production of green plum wine.?2?the growth characteristics and tolerance of the selected J-1 strain were studied,and the optimal temperature and p H value for the growth of the J-1 strain were determined.And tolerance to ethanol,glucose,sulfur dioxide,citric acid and temperature.The results showed that the optimal growth temperature and p H value of J-1 strain were 24?and 5.5 respectively.The maximum tolerance of J-1 strain to ethanol,glucose,sulfur dioxide,citric acid and temperature were 12%vol,50%,500mg·L^-1,50 g·L^-1and 55?,respectively.According to the morphological and molecular biological identification,J-1 yeast is the round yeast of dell spore.?3?composite greengage wine yeast fermentation,using single factor and orthogonal experiment on the compound yeast fermentation technology was studied,with the total acid,residual sugar,alcohol and sensory score as evaluation index,the optimum conditions for the process:the vaccine first J-1,inoculated time for 36 h,compound ratio of 1:1,total quantity of 5%,for 26?fermentation temperature,initial p H value of 4.5 and the ratio of 1:2,initial fermentation of material to water sugar was 20%,fermentation time was 9 d.?4?HPLC and GC-MS were used to evaluate the organic acid content and flavor of green plum wine brewed with the best compound yeast technology,green plum wine fermented with the original single bacteria?BV strain?or green plum fermentation broth.The results showed that:on the basis of original BV strain fermented wine,the total acid and volatile acid of compound yeast green plum wine decreased by 5.3%and 33.3%respectively,in which the total amount of malic acid and citric acid decreased by 3.67%and the sensory score increased by 11 points.39kinds of flavor substances were detected in BV single strain fermented liquor,while44 kinds of flavor substances were detected in compound yeasts fermented liquor.Among them,esters and alcohols were increased by 5.53%and 17.36%respectively,while acids and other types were decreased by 16.89%and 54.43%respectively.The total amount of aromatic substances in compound yeast green plum wine was higher than that in single fermented green plum wine.