Novel decaffeination of green tea using a special picking method and shortening of the rolling process

We have recently succeeded in manufacturing low-caffeine tea (LCT) by employing a special picking method in the 3rd leaf period and shortening the leaf-rolling process. In the present study, the effect of this special method on the content of other physiologically active substances, such as catechins, theanine, and vitamin C, as well as the mechanism of reduction of caffeine content in the LCT were investigated using capillary electrophoresis. By comparing the various components of tea leaves at different picking periods with or without shortening of the rolling process, it was found that the delayed leaf picking period and shortening of the rolling process used in the manufacture of LCT selectively reduced the caffeine content while retaining catechins, theanine, and vitamin C at a sufficient level. Therefore, our study demonstrated that this modified method may be useful in the manufacture of decaffeinated green tea.