Catechin– Bitterness & Astringency
Caffeine– Bitterness
Theanine & Amino Acids– Flavor & Sweetness
In this section you'll learn what's in a tea leaf, and about the effect of these specific ingredients in green tea: Catechin, Caffeine, the Amino Acids Theanine & Butyric Acid, Vitamins A, B1, B2, B3, C, E, F, K, P, & U, Chlorophyll, Minerals, Pectin, Saccharides, Saponin and a handy comparison of ingredients in green teas.
Catechin - Catechin is a tannin peculiar to green tea because the black tea fermentation
process reduces
catechins in black tea. Catechin is a powerful, water soluable
polyphenol and
antioxidant that is
easily oxidized.
Several thousand types are available in the plant world. As many as two thousand are known to have a flavon structure and are called flavonoids. Catechin is one of them.
Research aimed at finding the active compounds in green tea revealed that its protective effects are due chiefly to catechins. Tea contains four main catechin substances: EC, ECg, EGC and EGCg, all of which are inclusively called catechin. Epigallocatechin gallate (EGCG) is the most powerful of these catechins. EGCG as an antioxidant is about 25-100 times more potent than vitamins C and E. One cup of green tea provides 10-40 mg of polyphenols and has antioxidant effects greater than a serving of broccoli, spinach, carrots, or strawberries. The high antioxidant activity of green tea makes it beneficial for protecting the body from oxidative damage due to free radicals.
cathecin extraction from tea leaves shown in this chart
why in producing water soluble green tea powder green tea is extracted by using hot water. Isn't that can damage the structure of catechin containing in the leaves ??
BalasHapusOk nezi, I'll try to answer the question..
BalasHapusIn tea leaves also contain another compound like caffeine and tanin.
They both are dissolved in hot water. So, I think the reason why tea leaves should be extracted with hot water at firt is in order to dissolve the compounds beside catechin.