Optimization Of Native Saccharomyces Cerevisiae And Analysis Of Its Dry Red Wine Quality

In this paper,the effects of native yeast and commercial Saccharomyces cerevisiae on the quality of Cabernet Sauvignon and Merlot were studied.The basic characteristics of different Saccharomyces cerevisiae were compared.The native fermentation yeast with better fermentation performance was selected by simulated fermentation test.The dynamic changes of materials in the fermentation process of the preferred native Saccharomyces cerevisiae were studied.The analysis of the aroma components of the wines fermented by different strains was carried out by gas chromatography-mass spectrometry,and the sensory evaluation was carried out in order to screen out the high quality and local characteristics of Saccharomyces cerevisiae.The main findings are as follows:1.Through the basic characteristic test,the killing,hydrogen sulfide production and foam production of 4 native Saccharomyces cerevisiae(S12,S21,WJ1,Q12)and 4 commercial Saccharomyces cerevisiae(XR,DS,CEC01,CECA)Comparative analysis of sex and flocculation.The results showed that the three native Saccharomyces cerevisiae S21,WJ1 and Q12 met the fermentation requirements.2.The native yeasts S21,WJ1 and Q12 were subjected to simulated fermentation test.According to the comprehensive evaluation of physical and chemical indicators and fermentation time,native Saccharomyces cerevisiae WJ1 and Q12 met the fermentation standards of wine,and were identified as Saccharomyces cerevisiae by sequence analysis of 26S rDNA D1/D2 region.3.Different Saccharomyces Cerevisiae Fermented Merlot wines are mainly composed of alcohols,esters and acids.A total of 61 aroma components were detected.Compared with commercial brewing,the fermented substances of the local Saccharomyces cerevisiae are similar to the commercial brewing.The relative content of Qi2 alcohol is relatively low,the relative content of esters is relatively high,and the relative contents of acid substances and aldehydes and ketones are not much different.The relative content of alcohols and esters of Merlot wine fermented by WJ1 is moderate,and the content of acid substances and aldehydes and ketones is slightly higher.Among the alcohols,the content of 2,3-butanediol is the highest,the content of ethyl acetate is higher in the esters,and the content of orthoacetic acid and caproic acid in the acid substances is the main.According to the results of sensory evaluation,the native Saccharomyces cerevisiae Qi2 fermentation broth was slightly inferior to the commercial sauerkraut fermented Merlot wine.The scent was slightly insufficient,the aftertaste was short,the taste was not smooth,the body was light and the structure was slightly poor.The native S.cerevisiae WJ1 fermentation broth is superior to the commercial Saccharomyces cerevisiae CECA fermentation broth.The color is bright,the wine is transparent,the acidity is slightly heavy,the taste is not smooth,and the body structure is general.The native Saccharomyces cerevisiae and commercial Saccharomyces cerevisiae were subjected to single-fermentation fermentation tests on Meilu and Cabernet Sauvignon grapes respectively,and the dynamic physical and chemical indicators during the fermentation of different strains were monitored.In the fermentation process of Meilujing wine,the native Saccharomyces cerevisiae WJ1 fermentation broth The total acid and alcohol content is slightly higher,but it is not much different from commercial yeast.The reducing sugar,tannin,anthocyanin and total phenol are all between the commercial Saccharomyces cerevisiae fermentation broth;the reducing sugar content in Q12 fermentation broth is slightly higher than Commercial Saccharomyces cerevisiae fermentation broth has a slightly lower anthocyanin content,and other indicators are not much different from commercial ones.During the fermentation of Cabernet Sauvignon wine,the total acid content of the native S.cerevisiae WJ1 fermentation broth was slightly higher than that of commercial yeast fermentation broth,and the anthocyanin content was slightly lower;the content of tannin,anthocyanin and total phenol in Q12 fermentation broth was significantly lower than that.Commercial Saccharomyces cerevisiae,total acid,reducing sugar,alcohol content between commercial yeast fermentation broth.The native yeast meets the fermentation standards and can be used for the fermentation of Merlot and Cabernet Sauvignon.The sequence of 26S rDNA D1/D2 was identified as Saccharomyces and Saccharomyces cerevisiae.4.Different Saccharomyces Cerevisiae Fermented Merlot wines are mainly composed of alcohols,esters and acids.A total of 61 aroma components were detected.Compared with commercial brewing,the local Saccharomyces cerevisiae fermented Merlot wine aroma substances,the relative content of Q12 alcohols is relatively low,the relative content of esters is relatively high,and the relative contents of acid substances and aldehydes and ketones are not much different.The relative content of alcohols and esters of Merlot wine fermented by WJ1 is moderate,and the content of acid substances and aldehydes and ketones is slightly higher.Among the alcohols,the content of 2,3-butanediol is the highest,the content of ethyl acetate is higher in the esters,and the content of orthoacetic acid and caproic acid in the acid substances is the main.According to the results of sensory evaluation,the native S.cerevisiae WJ1 fermentation broth has typical fruity and fragrant but slightly insufficient,slightly sour taste,not soft,and the body structure is general,but the clarity,color and aroma are better than commercial Saccharomyces Cerevisiae CECA fermentation.liquid.The native S.cerevisiae Q12 color is inconsistent with the typical Merlot wine color,slightly tarnished,lack of fruit,short aftertaste,low body,underbalanced,rough,clear,aroma,taste and typicality are not as good as commercial Saccharomyces cerevisiae.Therefore,native Saccharomyces cerevisiae WJ1 can be used as a commercial strain for fermenting Merlot wines,and Q12 is of poor quality and is not recommended for use as a commercial strain.5.Native Saccharomyces Cerevisiae WJ1 Fermented Cabernet Sauvignon has the characteristics of low alcohol content,high ester and acid content compared to commercial Saccharomyces cerevisiae.Q12 is characterized by low alcohol content,slightly higher ester content and moderate acidity.Among the alcohols,the content of 2,3-butanediol is the highest,and the esters are mainly ethyl acetate.Combined with sensory evaluation results,it is concluded that native S.cerevisiae WJ1 is more typical in the fermentation of Cabernet Sauvignon wine,and is superior to commercial Saccharomyces cerevisiae.It has fruity aroma,rich aroma,outstanding aroma,long-lasting elegance and full body.The typicality is outstanding,while the color of Q12 is slightly light,the fruit fragrance and wine are not rich,the acidity is slightly lower,the aftertaste is insufficient,and the aroma,taste and typicalness are not as good as commercial brewing yeast.Therefore,native Saccharomyces cerevisiae WJ1 is suitable for fermenting Cabernet Sauvignon wine and can be used as a commercial brewing strain,while Q12 is not recommended as a commercial strain.