Simplified analysis of flavanols in matcha tea

Abstract

Matcha tea contains only the softer parts of the tea leaves and is finely ground. Therefore, extraction of the flavanols for analysis by HPLC is possible by a simpler protocol compared to the ISO 14502-2 method. 21 different simplified extraction methods were screened and five of them gave equal results as the ISO 14502-2 method. The simplest and fastest method consists of extraction by ethanol + water (7 + 3, v + v) at room temperature with ultrasonication. This method was validated by determining accuracy, intraday and interday repeatability. The simplified method was successfully applied to four traditional matcha teas and two powdered green teas from Japan. This method paves the way for time-saving, energy-saving and accurate analyses of flavanols in matcha tea.

Keywords: (−)-Epicatechin (PubChem CID72276); (−)-Epicatechin-3-O-gallate (PubChem CID 107905); (−)-Epigallocatechin (PubChem CID72277); (−)-Epigallocatechin-3-O-(3-O-methyl)gallate (PubChem CID 9804842); (−)-Epigallocatechin-3-O-gallate (PubChem CID 65064); Analysis; Benifuuki; Caffeine (PubChem CID2519); Camellia sinensis; Extraction; Green tea; HPLC; Matcha; Powedered tea.