The evolution of tea taste. The fresh tea leaf
contains rich stores of simple phenolic
compounds (catechin, left) that are colorless
and bitter but not astringent. When the tea
leaf is bruised or rolled, leaf enzymes and
oxygen combine the simple compounds into
larger ones with different colors and tastes.
Brief enzyme action produces a yellowish
compound(theaflavin, center) that is both very
bitter and astringent. More extensive enzyme
action produces a compound(theaflavin
digallate, right)that is moderately bitter and
astringent. As the phenolic molecules get
larger, they get progressively darker and
milder.
Making Tea