Research On Complex Fermentation Process Of Red Globe Grape Wine And Analysis Of Aroma Components

Due to the production season more concentrating and unease to storage of table grape,the rate of loss about 27%in grapes every year..In this study,red grape and glutinous rice juice were used as raw materials to compare and screen fermented yeast strains,and the response fermentation method was used to optimize the composite fermentation to produce red globe wine.The aroma components of the composite fermented red globe wine were analyzed and evaluated by headspace solid phase microextraction?HS-SPME?combined with gas chromatography-mass spectrometry?GC-MS?.Finally,the effects of complex fermentation by glutinous rice juice and traditional sugar on the quality of red wine were investigated.The research results provide a new technical route for the production of red globe wine by the composite fermentation process of fresh grape and glutinous rice juice.At the same time,it provides the necessary supplement for the sales of red grape fresh fruit,which is beneficial to the protection of red grape growers.The paper compared the effects of three yeasts?BV818,SY,RW?on the sugar content,acidity,alcohol content,pH,CO₂ emission,total phenolic content,total anthocyanin content and DPPH clearance rate in the fermentation mash,and the sensory evaluation of finished wines by quantitative descriptive analysis?QDA?.The results showed that the sugar content of BV818 yeast fermented wine decreased from the initial value of 21.1±0.2°Brix to 7.7±0.2°Brix at the 96 hour,and the alcohol content increased from the initial value to 10.7±0.26%.Suger reducing rate and alcohol production rate were significantly higher than other two yeasts?p>0.05?.At the same time,the red globe wine produced by BV818 yeast has the characteristics of high alcohol content,low residual sugar,low acidity and rich fruit flavor,high total phenolic content and total anthocyanin content,and strong antioxidant capacity.Therefore,BV818 yeast was selected as the fermentation strain of the complex fermentation red globe wine.BV818 yeast was used as the fermentation strain,and the alcoholicity of the final fermentation broth was used as the response value.The single-factor test combined with the response surface method was used to optimize the fermentation process of red globe and glutinous rice juice,and the optimal fermentation process was determined.The results showed that the optimum fermentation parameters were determined as fermentation temperature of 21?,yeast inoculation of 1.1 g/L,volum ratio 1:4,SO₂concentration 84 mg/L.Under these conditions fermentation time of 7 d,the alcohol content was 12.7%.The red globe wine obtained by the above optimized fermentation process was used as raw material,and the volatile aroma components of the wine were extracted by HS-SPME technology.The aroma components of the composite fermented red wine were analyzed by GC-MS combined with OAV method.Totally,39 kinds of aroma substances such as alcohols,esters,acids,ketones and enes were identified.OAV analysis indicated that 12 of the 39 volatile compounds contributed to the critical characteristic aroma.The components mainly included?-damascenone,ethyl caproate,ethyl caprylate,isoamyl acetate,ethyl caprate.The effects of sugar content,acidity,alcohol content,pH,CO2 emission,total phenolic content,total anthocyanin content and DPPH clearance rate of fermentation sputum during fermentation of complex fermentation and sugar-added fermentation red globe wine were compared.the results showed that the total phenolic content and antioxidant activity of the complex fermentation wine were significantly lower than that of the sugar-added fermentation wine?p<0.05?,but the composite fermentation could significantly improve the sensory score,alcohol content,hypoglycemic rate and wine production rate of red wine?p<0.05?.The aroma components analysis showed that 39and 36 aroma components were detected in the complex fermentation and sugar-added fermentation red globe wine,among which 28 kinds were common aroma components,and the main aroma components were?-damascenone,ethyl caproate,ethyl caprylate,isoamyl acetate,ethyl caprate.The main aroma characteristics of the two wines were consistent,but the volatile acid content of the sugar-added fermentation wine was higher than that of the complex fermentation wine?p<0.05?.