Abstract: The kinetics of extracting the soluble solid contents from black tea leaves in super-comminuted tea powder was studied.The Brixs of infusion was measured by digital refractometer at different temperatures from 40 to 80℃.The first order rate constantwas determined from the rate of increase of the Brixs concentration in the tea infusion time and the result was interpreted by usinga steady state model. The results showed that the first order rate constant of the super-comminuted tea powder was 1.27～2.22 times as large as that of black tea leaves, and that the Brixs increased when the extraction temperature increased.

Key words: super-comminuted tea powder, soluble solid contents, kinetics of extraction