"Nigel" writes:

This is due to chemical oxidation of the green tea catechins into
orange theaflavin - while the tea is sitting in your cup it reacts with
oxygen dissoved in the water - same reaction as would happen to make
black tea in a tea factory except that then it is catalysed by natural
tea enzymes.

So hot water can substitute for the enzymes destroyed by the firing of
green tea?

/Lew
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Lew Perin /
http://www.panix.com/~perin/babelcarp.html