Research On Brewing Technology And Quality Of Pueraria Distilled Liquor

Kudzu root is diverse in variety and rich in resources,and is a commonly used medicinal and food resource in China,which has high nutritional and medicinal value.However,kudzu has a short shelf life and is perishable and moldy,resulting in a rapid decline in its quality and a waste of resources.Therefore,kudzu needs to be processed,but now kudzu processing products are not abundant,less development and utilization,and there is less research on kudzu distilled liquor.In this paper,four yeasts fermented kudzu root,the optimal fermentation strain was determined,the response surface of kudzu wine fermentation conditions was optimized,the secondary distillation of kudzu fermented wine was carried out,and the aroma composition,quality and antioxidant capacity of kudzu distilled wine during the distillation process and aging period were studied,which provided a theoretical basis for the in-depth development of kudzu distilled wine.The main findings of the study are as follows:(1)Kudzu was fermented by Angel Yeast SY、Saccharomyces cerevisiae 1596、Saccharomyces cerevisiae 1383、and Saccharomyces cerevisiae 1398,compare several indicators such as alcohol content and reducing sugar after fermentation,get the results,Angel yeast SY is most suitable for the fermentation of kudzu,kudzu fermented wine has an alcohol content of 7.23%vol,the reducing sugar content was5.47 g/L,the total acid content was 3.33 g/L,the soluble solids was 6.33%,and the sensory score was 79.00 points.Based on a one-way trial,the fermentation conditions of kudzu fermented wine are optimized for response surface,the response surface model for the resulting fermentation conditions is:R=-47.02535+8.19167A+2.66458B+2.42361C+0.17500AB+0.18333AC+4.16667E-003BC-2.85000A~2-0.22813B~2-0.051389C~2.The effects of the three factors on alcohol content are,in order:yeast inoculation(29)fermentation temperature(29)fermentation time.The best crafts for kudzu are:yeast inoculation amount 2.6%,fermentation time 7 d,fermentation temperature 28°C,under this condition,the alcohol content is 7.35%vol,which is close to the model value of 7.42%vol,indicating that the model can predict the fermentation conditions of kudzu very well.(2)The main aroma components in the first distillate and the secondary distillate were analyzed,the most important aroma components in the first distillate are isoamyl alcohol,phenethyl alcohol,caprylic acid,capric acid,3,4-dimethylphenol,isoamyl acetate,ethyl caprylate,phenyl acetate,ethyl laurate,ethyl palmitate,there are ten in total,accounting for 57.71%of the total peak area of the first distillate;The most important aroma components in the secondary distillation liquid are isoamyl alcohol,phenethyl alcohol,caprylic acid,capric acid,2,5-dimethylphenol,ethyl caprylate,ethyl acetate,ethyl laurate,ethyl palmitate,isoamyl capricate,ethyl tetratetrade,there are eleven kinds in total,accounting for 63.38%of the total peak area of the secondary distillate.(3)The aroma composition of kudzu distilled wine aged for three months,six months and nine months was analyzed,and the main aroma components in the three-month-old kudzu distilled wine sample were isobutanol,phenethyl alcohol,isoamyl alcohol,1-decanol,caprylic acid,ncapric acid,isoamyl acetate,ethyl caprylate,ethyl acetate,ethyl capricate,ethyl laurate,ethyl tetratetrade,ethyl palmitate,a total of fourteen kinds,accounting for 78.02%of the total peak area of kudzu distilled wine samples aged for three months;The main aroma components in the six-month-old kudzu distillery sample are isoamyl alcohol,1-decanol,butyl hydroxytoluene,isoamyl acetate,ethyl caprylate,phenylethyl acetate,ethyl capricate,ethyl laurate,decyl acetate,a total of nine,accounting for 79.63%of the total peak area of the six-month-old kudzu distilled distilled wine sample;After nine months of aging,the main aroma components in the kudzu distilled wine sample are isoamyl alcohol,phenethyl alcohol,caprylic acid,4-ethylphenol,isoamyl acetate,ethyl caprylate,phenyl acetate,ethyl capricate,ethyl laurate,ethyl palmitate,methyl palmitate,a total of eleven,accounting for 80.76%of the total peak area of the nine-month-old kudzu distilled distilled wine sample.The relative content of alcohol aroma components,acid aroma components,aldehyde aroma components,and alkene aroma components of kudzu distilled wine decreased,while the relative content of ester aroma components,ketones aroma components,and phenol aroma components of kudzu distilled wine increased.(4)After the two distillations,the alcohol content and total acid content of kudzu liquor showed an upward trend,and the alcohol content in kudzu distilled wine after two distillations was 39.8%vol,the total acid content was 0.59 g/L,the total ester content was 0.37 g/L,the soluble solids was 13.13%,the fusel oil content was 1.03g/L,the methanol content was 0.25 g/L,and the cyanide content was 0.10 mg/L;With the continuation of the aging time,the alcohol content,fusel oil,methanol and cyanide content of kudzu distilled wine gradually decreased,but the content of total acid,total ester and soluble solids still showed a stable upward trend;After nine months of aging,kudzu distilled liquor has an alcohol content of 36.07%vol,a total acid content of 1.07 g/L,a total ester content of 0.70 g/L,a soluble solids of 15.47%,a fusel oil content of 0.29 g/L,a methanol content of 0.05 g/L,a cyanide content of0.05 mg/L,and a sensory score of 79.64 points.(5)The DPPH radical clearance rate in Kudzu distilled liquor is 35.49%,hydroxyl radical scavenge is 97.14%,superoxide anion radical scavenge is 9.57%,ABTS radical scavenge is 68.23%,iron ion reduction capacity is absorbance of 0.47,and total antioxidant capacity is 0.045,comparing kudzu distilled spirits with commercially available distilled spirits,kudzu distilled liquor’s DPPH,hydroxyl group,superoxide anion,ABTS radical clearance,iron ion reduction capacity,and total antioxidant capacity were significantly higher than commercially available distilled spirits(p(27)0.05),and with the increase of aging time,the in vitro antioxidant capacity of kudzu distilled wine was also enhanced.