Mango Wine Aroma Producing Yeast Construction And Optimization Of Fermentation Process

Mango wine is a healthy fruit drink fermented from mango juice by yeast strains.Along with the changes in people's eating habits,the beautiful colour and unique flavor of mango wine bring a huge market space for its development.To improve the flavor quality of mango wine as the starting point,separation of mango wine yeast,selection of aroma-producing yeast and optimization of process conditions of mango wine was studied in this paper.The results were summarized as follows.1.Sixty yeast strains were isolated from the skin of mango.Through initial screening,thirty-eight strains which had aroma and vinosity in their fermentation liquid were screened out.After WL medium on the basis of the colony color and morphological identification,its preliminary divided into ten categories.After three stages of screening,thirteen strains with strong optimal fermentation performance were screened out,including six strains of yeast which has well tolerated in common conditions of fermentation production.By 26S rDNA analysis,the six strains as follow-up test strains.2.The six yeast strains were mango wine fermentation,by using the method of GC/MS analysised aroma components of six mango wine samples and mango juice sample.Total forty-five kinds of aroma components were analysised from the mango juice sample by GC/MS,and six wine samples were detected thirty-eight,forty-five,thirty-seven,thirty-nine,forty-six,forty-two kinds of aroma substances.By contrast,mango juice before and after fermentation changes of aroma substances of larger,and the fermentation of volatile matter about thirty in each strain fermentation sample were not kept.Mango juice fermentation generated a lot of new volatile substances,and the content of aroma substances are improved obviously.By comparing the six wine samples found that aroma composition and aroma content was obvious different and each sample had unique aroma substances.The alcohols and esters as the relative content of each wine samples were detected in the largest.Through the contrast between wine samples aroma components as well as the liquor color,clarity,aroma,taste and typical of the sensory evaluation,the DTM9 yeast fermentation of mango wine sample had obvious advantages relatived to the other five strains fermentation samples,then determined the DTM9 yeast strain as aroma-producing yeast eventually selected.3.The enzyme concentration,enzymatic time and temperature as three process conditions were determined by single factor test with the evaluation index of mango juice transmittance,determined three factors'level of the orthogonal experiment.Through the L9(34)orthogonal experiment of mango juice enzymatic hydrolysis processlfound three factors of influencing sequence of transmittance was enzymatic hydrolysis temperature,hydrolysis time,adding amount of enzyme.Enzymatic hydrolysis temperature and hydrolysis time had significant influence on mango juice transmittance.The oroptimal process conditions of mango juice enzymolysis were:enzyme dosage 0.14%,hydrolysis time 4 h,enzymolysis temperature 40?.Under these conditions,the transmittance of mango juice can reach more than 82%.Through the tests of Inoculation,fermentation temperature and initial sugar concentration in DTM9 yeast strain fermentation,determined the optimum fermentation conditions was inoculation 8%,fermentation temperature 28?,initial sugar concentration of 18%.