The concentrations of the major tea flavanols in nine green teas from
China and Japan have been investigated. Results show that epi-gallocat
echin (EGC) is the most prevalent flavanol and not epi-gallocatechin g
allate (EGCG) as previously thought. Studies of the equilibrium behavi
our of extraction of tea flavanols and caffeine into aqueous media at
80-degrees-C and 60-degrees-C for one of the teas, Sen Cha Uji Tsuyu,
indicate that extraction efficiencies are similar to that for extracti
on of soluble components from black teas. These studies also support t
he idea of EGC being the flavanol with the highest concentration. This
is of relevance to the current interest in tea flavanols as antimutag
enic agents in the treatment of cancers. From the flavanol content res
ults there appears to be a correlation between the amount of flavanol
and the price of the tea. It is possible that this might be used to ai
d the pricing of green teas at auction.