Changes in Contents of Some Ingredients During Heating of Green Tea

Relation between Changes of Chemical Compositions and Taste of Green Tea Part I

Abstract

Crude green tea was heated at 130°C for 30min, and at 160°C for 30min. The analyses some ingredients indicated that amino acids, free reducing sugars and vitamin C contents decreased remarkably during heating, while caffeine and total nitrogen hardly decreased. Furthermore, by use of theanine, glucose, (-)-epicatechin and caffeine as model compounds, the interaction among them during heating was investigated. The results indicated that the interaction between theanine and glucose was observed remarkably, and that between theanine and (-)-epicatechin was observed a little.