Study On The Yeast Breeding And Fermentation Technology Of Jackfruit Fruit Wine

Jackfruit have the rich pulp,unique taste,but its easy to grow and difficult to preserve after maturity,jackfruit is processed into fruit juice,chips,candied fruit and other food in addition to direct consumption.Jackfruit have the high sugar content,strong aroma,unique flavor.At present domestic most jackfruit fruit wine brewing technology is used in active dry yeast to ferment juice.In this study,the fermentation conditions of jackfruit wine were optimized by using natural fermentation screened yeast,mutagenesis modified yeast and commercial yeast as fermentation strains and than discuss the differences of three kinds of yeast fermentation wine aroma.The main research contents and results of this paper are as follows:(1)Strain A21 was obtained by jackfruit natural fermentation,throught the enrichment culture,isolation and purification and three-stage screening.The result of performance test showed that the yeast in 25 ? 35 ? can growth normal,the optimal fermentation temperature in 28 ? 31 ?;when the initial sugar content was 29 Bx,p H5.5,and the SO2 content was 80 mg/L,the alcohol production capacity was the strongest.When the initial alcohol content is 7%,the growth of yeast can be inhibited,and when the initial alcohol content is 11%,the tolerance limit of yeast alcohol content is closed to.(2)Chemical mutagenesis was carried out with A21 yeast,and improved to obtain Y42.The performance test for Y42 yeast,result showed that the yeast in 25 ? 35 ? can be normal growth,the optimal fermentation temperature is 30 ?;when the initial sugar content was 25 Bx,p H5.5,and the SO2 content was 80mg/L,the yeast had the highest alcohol production capacity.When the initial alcohol content was 9%,the growth of yeast was inhibited,and when the initial alcohol content was 13%,the tolerance limit of yeast alcohol content was approached.(3)On the basis of single factor experiment in the A21 and Y42 yeast,using the response surface optimization,get the best process parameters for A21 yeast: initial sugar 23 °Bx,25 ? fermentation temperature,fermentation time 6 d,quantity of 7%,on this condition of income jackfruit wine alcohol content of 10.2%;Y42 yeast optimum technological parameters for: initial sugar 23 ° Bx 6 d,30 ? fermentation temperature,fermentation time,quantity of 6%,on this condition of the jackfruit wine alcohol content of 13.3%.(4)Use GC-MS to analy the aroma components of wine fermented by commercial yeast,A21 and Y42.The results showed that there were 9 kinds of alcohols,27 kinds of esters,4 kinds of acids and 7 kinds of aldehydes and ketones in the wine fermented by commercial yeast.There are 13 kinds of alcohols,21 kinds of esters,5 kinds of acids and 3 kinds of aldehydes and ketones the wine fermented by A21 yeast.There were 9 kinds of alcohols,27 kinds of esters,4 kinds of acids and 4 kinds of aldehydes and ketones in the wine fermented by Y42 yeast.The proportion of alcohols was the highest(45.14%)in the wine fermented by Y42 yeast,among which the content of 3-methyl-1-butanol was the highest.Through the comparative analysis of aroma components of fruit wine fermented by three yeasts,the content of alcohol and esters in the wine fermented by Y42 yeast after mutagenesis was significantly higher than that of A21 yeast and commercial yeast such as the alcohol and esters were mainly 3-methyl-1-butanol,2-phenylethanol and ethyl decanoate.(5)Through the sensory,the physicochemical and the microbial indexes of jackfruit wine fermented by three kinds of yeasts.The sensory,physicochemical indexes of A21 and Y42 yeasts were significantly higher than that of commercial yeasts.Sensory,physicochemical and microbial indexes of jackfruit wine fermented by three kinds of yeasts all met the requirements of NY/T 1508-2017 "green food wine".