Study On Quality Evaluation Technology Of Luzhou-flavor Base Liquor Based On GC-QTOF MS

Baijiu is one of the six world distilled wines.Using koji and yeast starter as the saccharifying starter and starch(sugar)as raw materials,Baijiu is brewed by the process of cooking,saccharifying,fermenting,distilling,aging and blending.Base liquor is an unblended liquor produced by fermenting and distilling.A series of disorders have been caused in the market by the lack of a unified standard system for quality evaluation of base liquor.In order to safeguard the fairness of base liquor market and protect the interests of consumers,it is necessary to explore and establish a scientific,fast,efficient and low-cost base liquor quality evaluation method.The quality difference of the base liquor mainly depends on the variety and quantity ratio of its own trace aroma substances.Based on GC-QTOF MS,this paper qualitatively and quantitatively analyzed the flavor substances in the base liquor,and similarity analysis,factor analysis,cluster analysis and other methods have been used to analyze the base liquor of different quality grades,categories,years and brands,so as to explore and establish the quality evaluation method of the base liquor.This paper mainly includes the following research contents.(1)In this paper,similarity analysis,cluster analysis and factor analysis were used to study the base liquor samples of different quality grades,types,years and brands.The results showed that these three methods could effectively distinguish them.(2)In this study,factor analysis and regression analysis were used to establish the base liquor evaluation models of different quality levels.The evaluation model was based on the comprehensive score F value of 37 volatile components in the base liquor as independent variable and the comprehensive score of sensory evaluation as dependent variable.The evaluation model was Y=8.04806F+89.16666(R~2=0.9874),and its accuracy was 93.33%.It could basically judge the quality grade of Luzhou-flavor base liquor of excellent grade,first grade,second grade and third grade.(3)Factor analysis was used to study the influence of different volatile components on the quality of base liquor with different types and years.The contribution of each component to liquor quality was determined.When the cumulative contribution rate reached 85%,34 variable indices could be selected for different types of base liquor to replace 40 original indices effectively,and 20 variable indices could be selected for different years of base liquor to replace 40 original indices.(4)This paper studied the effectiveness of factor analysis in the elimination of volatile component with less contribution in the different brand base liquor.The results showed that 32 volatile components retained after factor analysis could effectively represent the original 38 components,and the base liquor samples from 6 wineries could be effectively classified.