蒙顶黄芽不同加工工序中色泽变化与品质相关性研究

研究不同加工工序制成的蒙顶黄芽干茶、汤色及叶底色泽，并进行色素成分检测及品质审评，分析干茶、汤色及叶底色泽L*a*b*值与各审评因子得分、色素含量、品质总分的相关性，为黄茶闷黄程度及色泽的评价提供一定的参考依据。以蒙顶黄芽加工过程中的茶样为试验材料，采用色彩色差计CR410测定干茶、汤色及叶底的L*a*b*值，再与干茶、汤色、叶底得分做显著性分析，与茶色素、叶绿素及品质总分做相关性分析。结果表明，干茶L*、a*、b*值与干茶色泽审评得分呈显著或极显著相关（P<0.05, P<0.01），茶汤L*、a*、b*值与汤色审评得分均呈极显著相关（P<0.01），其相关系数分别为?0.93、0.97、0.93，叶底L*、a*、b*值与叶底得分均呈极显著相关（P<0.01），其相关系数分别为?0.96、0.97、0.98；干茶、汤色及叶底的L值与茶色素含量呈极显著负相关（P<0.01），a*、b*值与茶色素含量呈极显著正相关（P<0.01）；干茶、汤色及叶底的L*值与叶绿素含量呈极显著正相关（P<0.01），a*、b*值与叶绿素含量呈极显著负相关（P<0.01）。蒙顶黄芽感官品质与L*、a*、b*值及色素之间的相关性表现为:与干茶 L *值、汤色L *值、叶底L *值、叶绿素a*、叶绿素b*含量均呈极显著负相关（P<0.01），与干茶a*b*值、汤色a*b*值、叶底 a*b*值及茶色素含量均呈显著或极显著正相关（P<0.05, P<0.01），除干茶a*值外，相关系数均在0.80以上。本试验表明，就各审评因子及品质总分而言，采用色泽Lab值测定方法可为黄茶色泽与品质相关性研究提供一定的理论基础。

Study on the Correlation between Color Change and Quality of Mengding Yellow Bud by Different Processing Procedure

This paper studied the color of Mengding yellow bud dry tea, soup color and leaf base made by different processing procedures, and carried out pigment component detection and quality evaluation. The correlation between L *, a*, b* value of dry tea, soup color and leaf base color and the score of each evaluation factor, pigment content and total quality score was analyzed, so as to provide a certain reference for the evaluation of yellow tea dullness and color. The L*a*b* values of dry tea, soup color and leaf bottom were measured by CR410 color difference meter, and then the significant analysis was made with the scores of dry tea, soup color and leaf base, and the correlation analysis was made with the scores of tea pigment, chlorophyll and total quality. The results showed that the L*, a*, b* values of dry tea were significantly or extremely significantly correlated with the scores of color evaluation (P<0.05, P<0.01), the L*, a*, b* values of tea soup were significantly correlated with the scores of color evaluation (P<0.01), and the correlation coefficients were ?0.93, 0.97, 0.93, respectively. The L*, a*, b* values of leaf bottom were extremely significantly correlated with the scores of leaf base(P<0.01), and the correlation coefficients were ?0.96, 0.97, 0.98, respectively . The L* value of dry tea, soup color and leaf base was significantly negatively correlated with tea pigment content (P<0.01), and the a* and b* values were significantly positively correlated with tea pigment content(P<0.01). The L* values of dry tea, soup color and leaf base were significantly positively correlated with chlorophyll content(P<0.01), while the a* and b* values were significantly negatively correlated with chlorophyll content(P<0.01). The correlation between sensory quality and L*, a*, b* value and pigment of Mengding yellow bud was as follows: It was significantly negatively correlated with L* value of dry tea, L* value of soup color, L* value of leaf base, chlorophyll a, chlorophyll b content (P<0.01), and significantly or significantly positively correlated with a*b* value of dry tea, a*b* value of soup color, a*b* value of leaf base and tea pigment content (P<0.05, P<0.01), except a* value of dry tea, The correlation coefficients were all above 0.80. The results showed that the lab value measurement method could provide a theoretical basis for the study of the correlation between the color and quality of yellow tea.