Novel Enzymatic Assays for the Measurement of Gallotannin, Amino Acids, and Glutamate in Green Tea Infusions: Analytical Results

Abstract

Novel enzymatic methods were used for the measurement of the levels of total gallotannin, total amino acids, and glutamrite in green tea infusions and in canned green tea drinks. Gallotannin was measured photometrically using rhodanine and tannase. Amino acids and glutamate were measured by a fluorometric flow-analytical method using L-amino acid oxidase and L-glutamate oxidase. The analytical results showed that the canned green tea drinks examined were similar in terms of chemical composition to infusions of the Japanese green tea called sencha.