茶树鲜叶主要生化成分与黑毛茶品质关系的研究

Research of the Relationship Between Semi-dark Tea Quality and the major chemical constituents of its Fresh Tea Leaves materials

本文对2008—2010年8个茶树品种春、夏、秋三季共72个样品的鲜叶生化成分与黑毛茶感官品质进行了相关性分析和回归分析。相关性分析表明，水浸出物含量、EGCG含量和儿茶素总量与黑毛茶感官品质得分呈显著正相关，而粗纤维含量与黑毛茶感官品质得分呈显著负相关。在进行共线性诊断的基础上，剔除了EGCG、EGC、GCG三个多重共线性自变量，建立了以感官审评得分为因变量，其余10个生化成分的含量水平为自变量的回归方程。回归方程中，标准化回归系数正相关大小顺序依次为儿茶素总量、ECG、水浸出物、总色素，说明这些成分对黑毛茶品质起正效作用，其中儿茶素总量的正效作用最大；负相关绝对值从大到小的顺序依次为咖啡碱、粗纤维、DL-C、EC、氨基酸总量，说明这些成分对黑毛茶品质起负效作用，其中咖啡碱的负效作用最大。

The correlation and regression between the chemical constituents in the fresh tea leaves and their semi-dark tea quality in 72 samples were analyzed in this study, including steamed green tea and semi-dark tea samples obtained from 8 different tea varieties which were processed in the spring, summer and autumn from 2008 to 2010, respectively. Correlation analysis showed that the water extract, EGCG and total catechins were significantly positive correlation with semi-dark tea quality, while the crude fiber showed a significant negative correlation. On the result of the linear diagnosis analysis, three multiple linear independent variables including EGCG, GCG, and EGC were removed, and then the regression equation were established with the sensory evaluation score as the dependent variable and the other 10 chemical constituents as the independent variables. The order of positive standardized regression coefficient in the regression equation were total catechins, ECG, water extract and total pigment, and the most positive relevant with the semi-dark tea quality was total catechins. In addition, it was found that the order of negative absolute values were the caffeine, crude fiber, DL-C, EC and total amino acids, and the maximum negative effect was caffeine.