Alterations in Chemical Constituents of Tea Shoot During Its Development

Abstract

The levels of the major chemical constituents in new shoots of tea trees were measured during their development. The first sprouts of three tea cultivars were analyzed from 1993 through 1995 for total nitrogen, caffeine, tannin, L-ascorbic acid, (-)-epicatechin (EC), (-)-epicatechin gallate (ECg), (-)-epigallocatechin (EGG), (-)-epigallocatechin gallate (EGCg) and (+)-catechin. Total nitrogen, caffeine and tannin decreased during the growth of new shoots. L-ascorbic acid also tended to decrease with the shoot growth, but notably decreased after rainfalls irrespective of the cultivar, and levels restored after successive sunny days. During the early growth stage, the levels of EC and EGC were slightly increased. However, the levels of ECg, EGCg and catechin were significantly lower as the new shoots developed.