基于感官评价及理化指标的来凤藤茶品质分析

Quality Analysis of Laifeng Vine Tea Based on Sensory Evaluation and Physicochemical Indexes

【目的】探究来凤藤茶感官评价与理化指标的相关性,构建藤茶品质评价模型。【方法】以来凤县不同乡镇的12个藤茶样品为材料,通过感官评价及理化指标测定,结合相关性分析、主成分分析和聚类分析,利用多元线性回归构建品质评价模型,并采用线性回归验证模型重现性。【结果】感官综合评分在85.42~92.59之间;12项理化指标变异系数在5.12%~30.81%之间,其中10项指标变异系数大于10%;理化指标间呈不同程度的相关性;主成分分析共提取3个主成分,方差累计贡献率为86.003%;聚类分析将12个藤茶样品聚为3类,类群Ⅲ有7项理化指标低于其他类群;多元线性回归得到评价模型为:综合评分=0.742×M_(二氢杨梅素)−0.574×N_(浑浊度),模型评分与感官综合评分线性回归相关系数为0.7826;模型重现性线性回归相关系数为0.6956。【结论】本研究可为藤茶特色产业品质评价标准的建立提供参考。

[Purpose]To explore the correlation between sensory evaluation and physiochemical indexes of Laifeng vine tea,so as to build a quality evaluation model.[Methods]A total of 12 samples of vine tea from different towns in Laifeng County were used as research materials.Through sensory evaluation and physiochemical indexes,combined with correlation analysis,principal component analysis(PCA),cluster analysis,multiple linear regression(MLR)were used to build a quality evaluation model and linear regression,and then the reproducibility of the model was tested.[Results]The comprehensive sensory scores ranged from 85.42 to 92.59;the coefficient of variation of 12 physiochemical indexes was from 5.12%to 30.81%,of which the coefficient of variation of 10 indexes was greater than 10%;physiochemical indexes were correlated in varying degrees.Three principal components were extracted by PCA,and the cumulative contribution rate of variance was 86.003%;cluster analysis clustered 12 vine tea samples into three groups,and seven physiochemical indexes of groupⅢwere lower than those of other groups;MLR obtained the quality evaluation model:comprehensive score=0.742×Mdihydromyricetin−0.574×Nturbidity,and linear regression correlation coefficient was 0.7826;the linear regression correlation coefficient of model reproducibility was 0.6956.[Conclusion]This study can provide a reference for the establishment of quality evaluation standard of vine tea characteristic industry.