Determination of substances characteristic of green and black tea- part1: content of total polyphenols in tea - colorimetric method using Folin-Ciocalteu reagent
This part of ISO 14502 specifies a method for the determination of the total polyphenol content of leaf tea and instant tea by a colorimetric assay using Folin-Ciocalteu phenol reagent [4]. It is applicable to both green and black tea products.