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

doi:10.11924/j.issn.1000-6850.2014-1519

Abstract

Abstract: 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.

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