Optimization of Main Fermentation Technology and Volatile Components Analysis of Snow Pear Loquat Wine

Using pear and loquat fruit as raw materials,the optimum conditions for the main fermentation of snow pear and loquat fruit wine were discussed in this study.Based on alcohol,pH,total acid,light transmittance,reducing sugar and sensory evaluation,the ratio of snow pear and loquat fruit,the addition of yeast inoculum and SO₂ were optimized by single factor experiment and orthogonal experiment. And the microbiological index of the finished product was determined.Further,the volatile components of snow pear and loquat fruit wine were analyzed by headspace solid phase microextraction combined with GC-MS analysis. The results showed that when the main fermentation was carried out with snow pear and loquat fruit as raw materials,the optimization resultsfor the volume ratio of snow pear and loquat fruit was 6∶4,the initial pH of the fermentation broth was 3.5,the addition amount of SO₂ was 80 mg/L,and the inoculation amount of yeast was 0.4 g/L. After 5days of fermentation,the alcohol content of the wine was 9.51%vol,the light transmittance was 91.5%,the total acid was 7.60 g/L,the pH value was 3.56,and the reducing sugar was 8.32 g/L. The fermented wine sensory evaluation score was 91 points under the optimal condition.The influence of various factors on the alcohol degree of fruit wine was:the initial pH>yeast inoculation amount>snow pear and loquat fruit volume ratio>SO₂ addition amount. The total bacterial flora of snow pear and loquat fruit wine was 11 CFU/mL and the coliform flora was less than 10^-9 MPN/mL,which were all in line with the standard. By analyzing its volatile components,30 volatile compounds were detected in snow pear and loquat fruit wine,with alcohol and esters accounting for 87.82% of the total volatile components,which played a positive role in the flavor of fruit wine.