Characterization Of The Difference Among Chinese Rice Wine Brewed From Different Varieties Of Rice

Rice that has been vividly compared to ‘the meat of wine’ in the brewing of Zhejiang rice wine is so important to the wine brewing.The glutinous rice,japonica rice and indica rice are usually used for wine brewing in southern area.The general materials are japonica rice and indica rice in the wine brewing process except the famous rice wine using glutinous rice.Shaoxin wine material gives priority to glutinous and its taste is mellow with rich smell.The wine in Shanghai are mainly composed of japonica rice and has fresh and crisp tastes.The wine have greatly difference of qualities when used different rice materials.The rice wine brewed from different origins,varieties and milling rates of rice is of difference in flavor.Different rice wine’s related performance such as water absorption-rates and enzyme characteristics are reported,but the influence of rice varieties to rice wine quality has not been studied in detail,only some simple empirical description.The differences of different varieties of rice wine brewing are not no clear.With the characteristic of rice wine brewing were discussed,the relationship between rice materials and wine-making can be better used for improving the quality of Chinese rice wine and liquor yield.To explore the characteristics of different types of wine brewing with different varieties of rice,we used japonica rice,round-glutinous rice,indica rice and long-glutinous rice as raw material and the basic physicochemical properties,rice steeping and vinification characteristics were studied and compared.The main conclusions are as follows:1.The rice-steeping has a significant effect on particle morphology and microstructure of rice flour.Scanning electron microscopy results showed that rice after 4 d steeping water swelling occurred and particle morphology was apparently disappeared.Water swelling for glutinous rice is much more easier in steeping process and loose pores of their structures are more prone to appear.The round-glutinous rice has the highest peak viscosity and setback value of the minimum after 4 d steeping.At the same time,the pasting temperatures of the 4 kinds of rice were both decreased and it was easy to cook before fermentation.2.The dynamic changes of rice milk during the steeping process show that: four kinds of rice seriflux,physical and chemical indicators of change is consistent,total acid and amino acid nitrogen showed increases slowly at first,then increased,finally tends to be gentle trend,reducing sugar increased first and then decreased trend.Total acid,amino nitrogen,reducing sugar content during the steeping process in the rice milk of round-glutious rice are at the highest level.The organic acid and amino acid composition analysis at the end of steeping showed that the organic acids in the rice milk is mainly lactic acid,followed by acetic acid;amino acids are mainly phenylalanine,isoleucine,gamma aminobutyric acid(GABA)and fine ammonia acid.Round-glutious rice’s amino acids and organic acids were the highest,and the differences between different tvarieties of rice significantly(p<0.05).3.Using headspace solid-phase microextraction(HS-SPME/GC-MS)combined with gas chromatography-mass spectrometry to analyse the differences of volatile components of steamed rice with different steeping time: 86 kinds of volatile components were detected with 2 h steeping.Non-hydrocarbon volatile are mainly phenolic aldehydes and ketones and the non-hydrocarbon volatile components of round-glutinous steamed rice is the highest which is 7910.45 ng/100 g.Steamed rice with 4 d steeping were detected a total of 82 volatile compounds and total volatile constituents increased significantly,mainly butyric acid and butyric acid esters,and non hydrocarbon flavor substances decreased;the main non-hydrocarbon volatile components detected are ethyl palmitate,indole,octanal,nonanal,2-methoxy-4-vinylphenol,1-octene-3-alcohol,pentyl furan,anti-2,4-nonadienal etc.4.Changes trend of basic physical and chemical indexes of 4kinds rice are consistent.Using round-glutinous rice to brew wine is easy for saccharification,fermentation speed faster,ethanol production rate is high,after the end of fermentation liquor of alcohol reached 17.6 %vol,and the residual sugar content is relatively higher.Total acid,amino nitrogen and pH of long-glutious rice fermented mash have been at a high level during the whole fermentation process.5.The amino acids in the fermentation broth of different varieties of rice were mainly sweet and bitter amino acids at the end of the fermentation and the content of sweet,bitter,fresh and astringent amino acids were significantly different(p<0.05).The amino acid content of indica rice’s fermentation liquid is the highest,followed by round-glutinous rice.The quantitative analysis showes that the volatile aroma compounds in the fermentation broth of 4 kinds of rice wine is the same,but the content of each compound is quite different.Volatile flavor compounds of the total content and alcohols content of the fermentation broth brewed with round-glutinous rice have obvious advantages and long-glutinous rice’s esters content is the highest in brewing wine.