Analysis of tannic acids by high-performance liquid chromatography

A method is described for the quantitative analysis of tannic acids by highperformance liquid chromatography (HPLC).Four tannic acids of different origin, Alep, Chinese, Sumac and Tara, were purified to serve as reference materials.HPLC calibration data in the normal-and reversed-phase modes were established against 2,3&trihydroxybenzoic acid as internal standard.Similarly, and using the same standard, calibration data for gallic acid were also determined.With the results it is possible to analyse tannic acid preparations for purity and gallic acid content.This application of HPLC is primarily of importance for the brewing industry.