Study On The Selection Of Yellow Peach Wine Saccharomyces Cerevisiae And Fermentation Technology

Yellow peach is a stone fruit belonging to the plum of Rosebush.It has rich nutritional value but also has the characteristics of storage intolerance and high acidity.The yellow peach wine is fermented by yellow peach juice,which can retain the nutrients in the fruit,increase the additional value,solve the problem of seasonal excess of yellow peach,enrich the diversity of the fruit wine market,and so make a better social and economic benefits.In this study,a strain of Saccharomyces cerevisiae suitable for yellow peach wine fermentation was screened,and then the fermentation parameters of yellow peach wine were optimized.Finally,the differences in physiochemical indexes among the yellow peach wine fermented by the optimized process and the commercial products are compared.The main results obtained in this research are as follows:In this study,more than 400 wild strains were screened from laboratory-preserved strains and natural fermentation broth of yellow peach juice.Finally,S.cerevisiae WT-21 was determined as the preferred strain based on the main brewing characteristics and the physiochemical indexes of yellow peach wine.Compared with the commercial strain D254,the sugar content was reduced by 33.04%,the volatile acid content was reduced by 16.36%,the alcohol compound content was increased by 73.1%,and the ester compound content was increased by 17.4%in yellow peach wine fermented by WT-21.In addition,the yellow peach wine has the most prominent fruity aroma and the best fullness.The effects of yeast inoculation,fermentation temperature,initial sugar content,p H,and nitrogen addition on the quality of yellow peach wine were analyzed through single-factor experiments,and the most suitable product type for yellow peach wine was determined through sensory evaluation.Furthermore,the sensory evaluation score was used as the response value to optimize the fermentation process of yellow peach wine.Finally,the optimal fermentation process parameters of yellow peach wine were:initial sugar content 195 g?L^-1,added nitrogen content 200 mg?L^-1,fermentation temperature 23℃,initial p H 3.4,yeast inoculation amount9.3?10⁶ CFU?m L^-1.Based on the fermentation process of S.cerevisiae WT-21,the growth and fermentation curves during the mixed fermentation of S.cerevisiae and non-S.cerevisiae and the quality characteristics of the yellow peach wine were studied.The results showed that the mixed fermentation of M.pulcherrima#30/S.cerevisiae WT-21 can significantly increase the content of glycerol（+57.52%）（P<0.01）,sorbitol（+19.44%）（P<0.01）,and ethyl ester compounds（P<0.01）.Further taking the glycerol,sorbitol and volatile compound content in#30/WT-21fermentation as indicators,the mixed inoculation process of yellow peach wine was determined as follows:S.cerevisiae WT-21 was inoculated 48 h after M.pulcherrima#30 inoculation and the inoculation ratio was M.pulcherrima#30:S.cerevisiae WT-21=10:1,other fermentation parameters are the same as single culture fermentation.The physiochemical properties and antioxidant capacity of the yellow peach wine obtained in this experiment were compared with three commercial products.The results showed that all indicators of yellow peach wine fermented in the laboratory were within the range specified by the national standard,with the minimum sugar content of 23.45 g?L^-1,low volatile acid content of only 0.39 g?L^-1,rich organic acid composition,and high amino acid content of 342.16 mg?L^-1,three kinds of in vitro antioxidant capacity are significantly higher than other products,a variety of important aroma compounds（OAV>1）high content.It is in line with people’s pursuit of healthy food and is a potential deep-processed product of yellow peach.