Abstract: Using one bud or one leaf and one bud as material, fresh tea leaves were spread continuously (78%~61%) and spread under different environment conditions, then fixed with liquid nitrogen and freeze-dried, respectively. The effects of spread process and spread environments on the change of tea polyphenols and catechin components were investigated. The results showed that the contents of tea polyphenols and total catechins decreased at beginning and then increased during spreading, total esters type catechins decreased gradually, epigallocatechin gallate (EGCG), gallocatechin gallate (GCG) and epicatechin gallate (ECG) decreased in amount during spreading, whilst epicatechin (EC) and epigallocatechin(EGC) increased, but gallocatechin (GC) could not be checked out in fresh tea leaves and spread tea leaves. With the precondition of that the moisture of spread leaves was controlled at 70%, there was obvious effect of environment temperature and humidity on the change of chemical components during spreading. Contents of tea polyphenols and total catechins decreased in low relative humidity (60%), but increased in high relative humidity (90%). The effects of middle relative humidity (75%) on tea polyphenols and total catechins was correlative with environment temperature.

Key words: quality green tea, spreading, biochemistry components, change