The tannin content of research tea varieties (including Kim Tuyen, PVI', PH8, PH9, PH10, Shan Chat Tien and LDP1) is 27.32 - 31.36 percent in which the lowest is Kim Tuyen variety with 27.32 percent, and three varieties with over 30 percent. Generally some tea varieties with tannin content lower than 30 percent used for "Ngan Kim" green tea processing with sweet taste are Kim Tuyen, PH10 and PVT. Soluble substance content of Kim Tuyen, Shan Chat Tien and PH10 varieties are lower than the control (LDP1) with significant limited level. The aromatic compound of Kim Tuyen, PH10 and PH8 varieties are higher than other ones and in capable of high quality Oolong tea processing. Kim Tuyen and PH10 tea materials are good for Oolong tea processing (taste sensory test score is 16.90 and 16.50 respectively)
PVI', Kim Tuyen and PH8 tea materials are good for Mao Tiem green tea processing (taste sensory test score is 16.40, 16.70 and 16.30 respectively).