Study On Brewing Technology Of Low-alcohol Bubbly Musalais

Musalais is an ancient wine in Xinjiang,known as the "living fossil ".In order to enrich the varieties of Musalais wine and further expand the product market,The suitable fermentation strain was selected,the new fermentation process was discussed,the termination fermentation method and clarification treatment method were optimized,and the bioactive substances and aroma components of the product were determined.The theoretical results of this study provide a scientific basis for the factory production of low-alcohol bubbly Musalais.The following conclusions were obtained:(1)Five commercial yeast strains(M47?EC1118?71B?D254?RW)were used for the fermentation test of single and double yeast,and the fermentation speed,fermentation power,and sensory characteristics of the products were comprehensively evaluated.The results showed that when the ratio of yeast EC1118 and D254,inoculation was 3:2,the product had good taste and harmonious aroma,which could be used as a suitable fermentation strain for low-alcohol bubbly Musalais.(2)The effects of fermentation temperature,yeast inoculum,and initial sugar content on the comprehensive properties of the products were studied by single factor test and orthogonal test.As a result,the optimum conditions for low-alcohol bubbly Musalais fermentation were 18% initial sugar content,20?fermentation temperature,0.8% yeast addition,and 120 mg/Lheavy potassium sulfite addition amount.(3)Optimized heat treatment,low-temperature-yeast separation,and low-temperature-ultrasonic treatment were selected as the methods to terminate fermentation.As a result,the sulfur content is 120mg/L,and the effect of ultrasonic treatment for 25 minutes is the best.(4)The optimum conditions for clarification of low-alcohol bubbly Musalais were obtained by freezing,centrifugation,membrane filtration,and chitosan-soap soil compound clarification.The results showed that the food-grade polypropylene(PP)cotton filter membrane with 0.22 ?m had the best clarification effect.(5)The contents of total phenol,total flavonoids,proanthocyanidins,and five monomer phenolics in the product were determined,and the aroma components were analyzed.The results showed that the contents of total phenols,total flavonoids,proanthocyanidins and five kinds of monomer phenols in low-alcohol bubbly Musalais were higher than those in commercial Musalais.The contents of total phenols,total flavonoids,proanthocyanidins,catechins,ferulic acid,resveratrol and quercetin were 850 mg /L,580 mg /L,270 mg /L,23.42mg/L,0.68mg/L,0.73mg/L,respectively 4.33mg/L.A total of 101 kinds of aroma components were detected,including 26.316mg/L isoamyl alcohol with apple brandy aroma and pungent flavor;22.68mg/L methyl formate with ester aroma;21.34mg/L phenylethanol with rose aroma;17.02mg/L isoamy L acetate with banana aroma;22.56mg/L ethyl caproate with koji aroma and pineapple aroma;35.02mg/L octanoic acid 15 mg /L,presenting fruit aroma.Through sensory analysis,it can be concluded that low-alcohol bubbly Musalais has pleasant color,sweet and sour taste,prominent fruit aroma and unique burnt aroma.