Study On Quality Changes And Accelerating Aging Method Of Citrus Fermented Wine During Aging Process

In this study,citrus fermented winecitrus fermented wine made in laboratory was used as raw material.The main functional components,methanol,fusel oil and flavor compounds in citrus fermented wine were determined from the end of main fermentation to 12 months of aging.In order to determine the best drinking time and shelf life of citrus fermented wine,the quality changes of citrus fermented wine during aging process was studied.At the same time,the technology of rapid aging of citrus fermented wine was studied,and a better method of rapid aging was obtained,it provided a theoretical basis for improving the productive efficiency of citrus fermented wine.The main results were as follows:(1)Changes of main functional components in citrus fermented wine during aging processThe total flavonoids and limonin analogues(i.e.limonin and nomilin)in citrus fermented wine during aging were detected by spectrophotometry and high performance liquid chromatography,respectively.The results showed that there were no significant changes in limonin and nomilin during aging,but the total flavonoids were decreased slightly.Compare with the end of main fermentation,the total flavonoids were decreased by 14.57% after 12 months of aging.(2)Changes of methanol and fusel oil in citrus fermented wine during aging processThe methanol and fusel oil(i.e.isobutanol and isopentanol)in citrus fermented wine aging process were detected by gas chromatography.The results showed that the content of methanol and fusel oil was decreased gradually during aging.After 12 months of aging,methanol and fusel oil were decreased by 29.00% and 31.35% respectively compared with the end of main fermentation.And the methanol content is 164.07 mg/L,which meets the limit of methanol in the national standard.(3)Changes of flavor substances in citrus fermented wine during aging processMonosaccharides and organic acids in citrus fermented wine during aging were detected and analyzed by ion chromatography and high performance liquid chromatography,respectively.The results showed that the main monosaccharide components in citrus fermented wine were glucose,fructose,galactose,arabinose and xylose.During aging,the content of glucose and fructose was decreased by 61.79% and 56.26% respectively,but the galactose,arabinose,and xylose had no obvious change.The content of total sugar in citrus fermented wine was decreased by 41.69%.The main organic acids in citrus fermented wine were citric acid,tartaric acid,acetic acid,lactic acid,malic acid,ascorbic acid and oxalic acid.During aging,the contents of citric acid,tartaric acid,ascorbic acid,oxalic acid and malic acid were decreased by 15.75%,35.11%,48.75%,47.48% and 12.17% respectively.And the content of lactic acid and acetic acid was increased by 6.77% and 5.43%,respectively.The content of total acids in citrus fermented wine was decreased by about 16.85%.After 12 months of aging,the acidity and astringency of citrus fermented wine was decreased and the palatability was improved.The volatile aroma components of citrus fermented wine during aging were identified and analyzed by solid phase microextraction combined with gas chromatography-mass spectrometry.The results showed that the alcohols and the esters were the main aroma components in the aging process,and the sum of their relative contents was more than 80%.The main aroma components are phenylethanol,isoamyl alcohol,ethyl octanoate,and so on.The relative content of esters aroma components was increased,the relative content of alcohols,acids,phenols and aldoketones aroma components was decreased gradually,and the relative content of hydrocarbons aroma components increased slightly.After 12 months of aging,the citrus fermented wine was full-bodied and harmonious.The fuzzy sensory evaluation was used to evaluate the sensory quality of citrus fermented wine.The results showed that the taste and flavor of aged citrus fermented wine were improved.Compared with the end of main fermentation,citrus fermented wine had harmonious aroma and soft taste,and sensory score increased from 75.9 piont to 83.8 piont after 12 months of aging.(4)Study on accelerating aging method of citrus fermented wineThe aging of new citrus fermented wine was speeded up by ultrasound,heating,microwave and irradiation.The basic physical and chemical values and sensory scores were considered as evaluation indexes.The results showed that the effect of irradiation on aging of new citrus fermented wine was the best,and the optimal irradiation dose was 1000 Gy.After irradiation aging treatment,the contents of methanol and fusel oil were decreased by 51.69% and 47.86%,respectively.The sugars increased slightly and the acids decreased slightly in citrus fermented wine.The esters aroma was increased and the alcohols aroma was decreased.The aroma was mellow and harmonious,the sensory score was 85.3 points,and slightly higher than the 12-month-old citrus fermented wine.