不同浸提条件下红茶色素浸出变化研究

以云南滇红工夫红茶为样品，研究了不同浸提次数、浸提时间下红茶色素浸出的变化。实验结果表明：色差L*a*b*随浸提时间及浸提次数变化显著，浸提2 次后茶汤色差a*值均为（+）值，浸提4 次后则均为（-）值；不同色素在相同浸提条件下浸出率不同，浸出率大小为TB最大，TR、TF次之，且TR、TF两者之间差异较小；随着浸提次数的增加，浸提茶汤的色差L*a*b*参数与色素TF、TR、TB含量差异逐渐减小，其值或含量趋于相同；在浸提时间为30 s 时，TF、TR、TB累积浸出率同浸提次数之间符合零级动力学方程，在浸提时间为1、3、5 min 时则绝大多数符合一级动力学方程；色素含量同色差值之间存在极显著相关关系，且相关系数大小为RTB>RTR>RTF。试验结果对探究色素的溶解规律与显色特性有着实际意义。

Research of Changes of Dissolution of Black Tea Pigment due to Different Infusion Condition

Changes of dissolution of black tea pigment due to dissolution interval and dissolution time were studied taking Kungfu black tea made in Yunnan Dianhong as sample. The results showed that L*a*b* changed significantly with dissolution interval and dissolution time. After samples were dissolved for 2 times, a* values of tea infusion were all ( ) while were all (-) when being dissolved for 4 times. TB had the highest leaching rate followed by TR and TF, while quite small difference of leaching rate could be discriminated between TR and TF. As the dissolution time increased, difference of L* values between the two adjacent dissolution time gradually decreased, tending to be the same value. This phenomenon also applied to a* and b* values, as well asthe content of TF, TR and TB. When the dissolution interval was 30 s, the relationship between ALR (the accumulative leaching rate) of the 3 kinds of tea pigment and dissolution time respectively matched the kinetic equation of zero level while mostly the kinetic equation of one level at dissolution interval of 1 min, 3 min and 5 min. Quite significant correlation was observed between content of tea pigment and values of chromatic aberration, and the correlation coefficient was RTB>RTR>RTF. This experiment was of practical meaning in exploring the dissolution pattern and coloration attribute of tea pigment.