Study On The Quality Of Two Wine Grapes And Their Wine Cultured On The Southern Slope Of Jiufeng Mountain

In this thesis,three groups of experiments were designed to determine the factors affecting the aroma components of wines: the quality of the grapevine Cabernet Sauvignon and Merlot in the front slope of the Jiufeng Mountain,and the evaluation of the single varietal wine.The optimization of fermentation temperature for different yeasts at different fermentation times for Sauvignon and Merlot;optimization of different oak barrels and different aging time for Cabernet Sauvignon and Merlot grapes;and the aroma components of wine grapes and wine were studied by GC-MS and other methods,combined with physical and chemical indicators.The sensory analysis demonstrated the quality characteristics of grape and grape wine cultivation on the front slope of Jiufeng Mountain,and its key fermentation process.The results were as follows:1.Grapes planted on the front slope of Jiufeng Mountain In 2017,the collection period of Cabernet Sauvignon and Merlot was concentrated around September 26 th.The sugar content of mature fruits was more than 200g/L,and the acid content was about 6g/L.The sugar-acid ratio was above 36,the tannin content was 21.65 ~ 27.14 mg/g,the total phenol content was 31.82 ~39.77 mg/g,the total anthocyanin content was 7.72 ~ 8.31 mg/g,and Cabernet's total phenolic and tannin content was higher.The total anthocyanin content was low,the total phenolic and tannin content of Merlot was high,the total anthocyanin content was low,and both Cabernet Sauvignon and Merlot could reach maturity and were suitable for cultivation;A total of 20 volatiles were detected in the mature fruits.The content of alcohols and aldehydes are relatively higher in the total substarres of Cabernet Sauvignon,the contentof esters is relatively lower.The relatively more aroma components are alconols aldenydes and acids in Merlot the esters is relatively lower.2.The main aroma components of different yeasts for the fermentation of Cabernet Sauvignon wine were consist of alcohols,esters and organic acids.The relative content of different substances from the highest to the lower is below: alcohols,esters,organic acids.The relative contents of isoamyl alcohol,phenylethyl alcohol and p-hydroxyphenylethyl alcohol were relatively higher in the total alcohols,and the relatively content of ethyl isovalerate was relatively higher in the total esters.The wine which was fermented by Frech Novezymes Excelleace Ds yeast at 22°C for 15 days,has more total phenols,single Ninghe,the total anthocyanins and the largest number of aroma substances.Among the aroma substances,there are 30 kinds of esters,the amount of special esters is 16.The relative content is also higher.3.The main aroma components of Merlot wine fermented by different strains were composed of alcohols,esters and organic acids..The relative content of different substances from the highest to the lower is below: alcohols,esters,organic acids.The relative contents of isoamyl alcohol,phenylethyl alcohol,p-hydroxyphenyl alcohol,isobutanol,color alcohol,(2R,3R)-(-)-2,3-butanediol were relatively higher in the total alcohols.and the relative content of ethyl isovalerate,ethyl caprylate were relatively higher.The wine which was fermented by Frech Novezymes Excellence XR yeast at 26°C for 15 days has more total phenols,single,tannins,total anthocyanins and the largest number of aroma substances.and the relative content was also high.4.A total of 57 aroma components were detected in different types of oak barrels,different degrees of baking,and different aging times.The main aroma components were consist of alcohols,esters and organic acids,the relative contents of isoamyl alcohol,phenylethyl alcohol,isobutanol p-hydroxyphenylethanol,(2R,3R)-(-)-2,3-butanediol,kang alcohol were relatively higher in the total alcohols,and the relative contents of ethyl L-lactate and diethyl succinate were higher in esters.The relative content of whiskey lactone was significantly higher than the Cabernet Sauvignon wine which was without oak barrel aging.The Cabernet Sauvignon wine which was aged for 6months French South-western oak barrels has the best quality.