Quality Analysis Of Table Grapes And Their Distilled Liquors

In recent years,the planting area and output of table grapes in my country have continued to increase,but it is faced with a series of industrial problems,such as overcapacity leading to unsalable products caused by the centralized listing of table grapes.In fact,table grapes not only have direct economic value,but also can be put into industrial production as a wine-making raw material.However,the existing wines mostly use wine grapes as raw materials,and table grapes are rarely used.At the same time,as far as China is concerned,brandy is also facing the problems of less varieties of raw materials and single product structure.To this end,this study took Summer Black,Hutai No.8,Yellow Rose,Giant Rose and Moldova five fresh food species from Shaanxi area as the research object,and the wine-making variety Ecolly as the control.The fruit quality,vinification characteristics and distilled liquor quality of table grapes were analyzed to explore the feasibility of the process of making distilled liquor from the table grapes,and to explore the varieties suitable for making distilled liquor.In order to improve the production structure of the grape industry,increase the economic value of table grapes,and enrich the variety diversity of brandy wine,the theoretical and practical basis was provided.The main results are as follows:(1)During the monitoring of grape maturity,with the accumulation of reducing sugar content,the total acid content is gradually decreasing.When grapes are harvested,the total acid content is controlled at 7-10 g/L,and the reducing sugar content can reach 100 g/L,which meets the raw material standards for brewing and distilling wine.The content of total phenols and tannins in the skins of Giant Rose grapes is the highest,the content of anthocyanins in the skins of Moldova grapes is the highest,the content of flavonoids and flavan-3-ols in the skins of Yellow Rose grapes are the highest,and the contents of flavonoids,flavan-3-ols,total phenols and tannins in the skins of Ecolly grapes are the lowest.(2)In all wines,the p H value is 3-4,which is slightly acidic;the residual sugar content is less than 2 g/L;the alcohol content is less than 10%vol;the volatile acid content is less than 1 g/L;the dry extract content is 20 g/L,all meet the requirements of the national standard GB75038-2006.The content of tannins and flavonoids in the Summer Black,Giant Rose and Moldova wines is lower than that of the Ecolly wine,and the contents of total phenols and flavan-3-ols in fresh wines are lower than the Ecolly wine.The abundance of aroma substances in the Ecolly wine is the highest.The abundance of the Moldova and Summer Black wine is higher,and the abundance of aroma substances in the Hutai No.8 wine is the lowest.The contents of esters in the Hutai No.8 and Giant Rose wines are the highest,both above 60%.While the contents of esters in the Summer Black,Yellow Rose,Moldova and Ecolly wines are lower than that of alcohols;The content of acidic substances in the Moldova and Ecolly wine is relatively high,the Summer Black wine has the highest content of aldehydes and ketones,and the Giant Rose wine has the highest content of terpenoids.Therefore,the types and contents of the aroma substances in table varieties wines are significantly different from those in Ecolly.(3)According to the cluster analysis and principal component analysis of the main aroma substances in six wines,the aroma contents of the Hutai No.8 and Giant Rose wines are similar,and the the aroma contents of the Summer Black,Moldova,Yellow Rose and Ecolly wines are similar.Similarly,the Moldova,Hutai No.8 and Ecolly wines are rich in aroma substances,while the Giant Rose wine’s richness of aroma substances is higher,and the Yellow Rose wine contains the least amount of aroma substances.In addition,the sensory evaluation scores of the Summer Black,Hutai No.8 and Giant Rose wines are higher than those of Ecolly,while the sensory evaluation scores of Moldova and Yellow Rose wines are lower than that of Ecolly.So,the wines made from Summer Black,Hutai No.8 and Giant Rose have a strong aroma,harmonious taste and good quality.(4)Compared with brewed wines,the p H of distilled liquor increases,the content of titratable acid,volatile acid and dry extract decreases,the richness of aroma substances increase,and the content of the same aroma substance doubles.Among them,Ecolly distilled liquor has the richest aroma substance abundance.table grape distilled liquor has the highest aroma substance abundance in the Giant Rose.Summer Black,Yellow Rose and Moldovan distilled liquors have similar aroma substances.The content of alcohols in the Giant Rose distilled liquor is similar to that of esters,and the content of alcohols in other distilled liquors is significantly higher than that of esters.Among them,the total alcohol content in the Moldovan distilled liquor accounts for up to 61.20%.The Hutai No.8,Yellow Rose,Giant Rose and Ecolly distilled liquors contain more and similar acids in content.The content of aldehydes and ketones in distilled liquor from table grapes is lower than that of Ecolly,and The content of terpenes was higher than that of aldehydes and ketones.the content of terpenoids in the Giant Rose distilled liquor is the highest.so there are obvious differences in the types and contents of aroma substances in different distilled liquors.(5)According to the cluster analysis and principal component analysis of the main aroma substances in distilled liquors,the main aroma substances in the Moldova and Ecolly distilled liquors are similar.The main aroma substances of the Giant rose,Yellow Rose,Summer Black and Hutai No.8 distilled liquors are similar to that of Hutai No.8 distilled liquor.Aroma substances of Hutai No.8 distilled liquors is richest.In addition,the sensory evaluation scores of Summer Black,Giant Rose and Yellow Rose distilled liquors are higher than those of Ecolly,while the sensory evaluation scores of the Moldavian distilled liquor are similar to those of the Ecolly,while the sensory evaluation scores of the Hutai No.8 distilled liquor are slightly lower than those of Ecolly.Therefore,the Summer Black,Giant Rose,Yellow Rose and Moldova are more suitable for distilled liquors.