Measuring flavonols in tea leaves

In collaboration with the National Agriculture and Food Research Organization (NARO), Shimadzu Corporation has been developing a simple, quick and accurate method for analysing functional components in agricultural and food products. This report introduces a quantitative method for flavonol analysis in tea leaves and presents the results obtained from two types of tea leaf.

Flavonols, a kind of polyphenol, are classified into flavonoids. To determine the content of flavonols, generally, the glycosides are hydrolysed to provide only the aglycone form rate. In this App Note, we present an analysis method for flavonols (shown in Table 1) which was developed to determine the contents of glycosides and aglycone without hydrolysis.