FOOD. Science. Technology. Quality

Food. SCIENCE. Technology. Quality

Food. Science. TECHNOLOGY. Quality

Food. Science. Technology. QUALITY

Authors

PRZEMYSŁAW KRAWCZYK, BEATA DRUŻYŃSKA

Title

Comparison of determination of catechins in green and black tea leaves using vanillin assay and HPLC-method

Abstract

The objective of this study was compare standard chemical method (vanillin assay) to determine total catechins with HPLC-method and effectivness of extraction catechins from green and black tea leaves using two kinds of solvents. The (+)-catechin, (-)-epicatechin, (-)-epigallocatechin gallate using high performance liquid chromatography method and total catechins using vanillin assay were determined. The compounds were extracted using two kinds of solvents: acetone:water (7 : 3) and methanol:water (8 : 2). The average of total catechins determined by vanillin assay was from 2.76 g to 8.94 g/100 g d.m. depending on kinds of teas and used extract solvents. The most of catechins (8.94 g/100 g d.m.) were extracted from green tea leaves by acetone solution and at least (2.76 g/100 g d.m.) from black tea leaves by methanol solution. The total rate of content (+)-catechin, (-)-epicatechin and (-)-epigallocatechin gallate determined using HPLC-method was from 2.63 g to 13.45 g/100 g d.m. The mixture acetone:water (7 : 3) has twice higher effectivness of extraction in relation to mixture methanol:water (8 : 2). HPLC-method made possible to determine a higher quantity of analysed catechins in comparison to chemical method (vanillin assay).

Keywords

tea, catechins, vanillin assay, HPLC

Download