Teanin and amino acid in tea

Amino acid is the generic term of chemical compound made up of amino and acid. Within the tealeaves, large amount of non-aqueous amino acid is contained as one of the compound elements of protein. However, aqueous amino acid is supposed to have strong effect on the taste and quality of green tea, especially for Gyokuro and fine quality green tea. Tea contains more than 20 kinds of free amid acid, and teanin. Other major elements in tea are glutamate acid, arginine, asparagines acid, glutamate, and serine, and they are consisting 98% of all the free amino acid contained in the tea. Since fine quality green tea contains more teanin than regular quality green tea, teanin is believed to be a source of the flavor. However, in recent study, we understand the winning tea at Japan tea fair had great amount of arginine. Since arginine and glutamine provide much more strong taste, than teanin, we have to say that besides tannin, arginine and glutamine acid are greatly adding the flavor on tea. The tannin in green tea ensures that our brain cells do not lack energy. It also controls stress by protecting the nervous system against overstimulation.

(Muneyuki Nakagawa)