Isolation And Identification Of Saccharomyces Cerevisiae Form East Foot Of Helanshan Moutains Of Ningxia And Fermentation Characteristics

With the development of China's wine industry,brewing with local characteristics of the characteristics of wine has become a trend.The aroma of wine mainly includes raw materials(a class of aroma),brewing incense(two types of aroma)and fragrant incense(three kinds of aroma).Brewing incense mainly from the brewing yeast,different yeast metabolites different brewing wine style is different.Long-term use of commercial wine yeast brewing wine,leading to increasingly homogenization of wine,but also a waste of wild wine yeast resources.China's wine-producing areas of the main environment,the characteristics of the different characteristics of the Saccharomyces cerevisiae,in the natural environment to breed with the local characteristics of the wine brewing yeast,you can avoid the wine homogenization of the phenomenon,and effectively enhance the quality of our wine.China's main wine-producing areas of the environment,the characteristics of the different characteristics of the Saccharomyces cerevisiae are different in the natural environment to breed with the local flavor of the wine with the characteristics of the wine yeast,wine can avoid the homogenization of the phenomenon,and effectively enhance the quality of our wine.In this study,we sampled 11 sites from the eastern part of Helan Mountain,Ningxia.Then isolated and identified the Saccharomyces cerevisiae.The strains were identified by WL medium and nitrogen source assimilation experiment.And the growth curve,glucose tolerance,S02 tolerance and alcohol tolerance were determined to breed Saccharomyces cerevisiae with excellent fermentation performance.The yeast with good fermentation performance was fermented to determine its alcohol production and fermented residual sugar,and molecular identification.Then the isolated strains of Saccharomyces cerevisiae were subjected to single strain fermentation experiments,and the volatile compounds produced by GC-MS were analyzed and determined.1.Eleven samples from the eastern part of Helan Mountain were collected and purified,and 1326 strains were isolated.Then 28 strains of Saccharomyces cerevisiae were screened by WL medium morphology and lysine assimilation performance.2.The results showed that the glucose tolerance,S02 tolerance,alcohol tolerance and growth ability were measured by absorbance method.The results showed that:10 strains of wild Saccharomyces cerevisiae:the potential as excellent Saccharomyces cerevisiae in tolerance and growth ability,Yeast and 14 commercial Saccharomyces cerevisiae fermentation experiments,compared with the fermentation products found that the separation of 10 strains of wild yeast has a considerable performance with commercial strains.3.The results showed that the volatiles produced by different yeast were used to determine the volatile substances in the fermentation broth by GC-MS.The results showed that the volatiles produced by different yeast The results showed that the strains LS2,LS70,LS73,LS78 and YGX27 could be used as brewer's yeast for brewing fine wines by analyzing the ratio of different kinds of fermentation products,the type of fermentation products and the ratio of alcohol to ester.4.By comparing the five kinds of wild wine yeast and 14 commercial brewer's yeast fermentation products found that the proportion of different species accounted for little difference,some of the leading role in the wine can be detected,and the content is not much difference.It is believed that the isolated Saccharomyces cerevisiae has comparable performance to commercial strains.14 strains of commercial Saccharomyces cerevisiae were not detected in the fermentation product of wild Saccharomyces cerevisiae.Strain LS2 was detected in heptaldehyde,octanal and ethylphenylethanol.The strain LS70 detects 6-ethyl-3-octanol and nonanone.Strain LS73 detected 3,3-dimethyl-1,2-butanediol,3-methyl butyl ester,strain LS78 detection of linalyl butyrate,The results showed that strains LS2,LS70,LS73 and LS78 had regional potentials,but further study was needed to compare the characteristics of yeast tolerance,fermentation characteristics,aroma characteristics and material characteristics.5.The strains LS2,LS70,LS73 and LS78 Saccharomyces cerevisiae were identified by the 26S rDNA technique,which was consistent with the speculation of Saccharomyces cerevisae and the use of WL medium and nitrogen source utilization,but further study was needed Its uniqueness.