Spectrophotometric Method for Simultaneous Determination of Anthocyanogens and Catechins (Tanninogens)
Abstract An earlier method for the simultaneous determination of anthocyanogens and catechins (tanninogens) in beer, wine, and brewing materials has been modified to include Polyclar AT and Polyamide Woelm 400 as the adsorbents. The results are presented, along with the values obtained using Nylon-66 for comparison. Nylon-66 and Polyamide Woelm 400 are the adsorbents of choice, yielding similar results, while Polyclar AT gives lower tanninogen values. The method is further applied to determine the anthocyanogen and catechin contents of solids, without the use of tanninogen adsorbents. Lyophilized beer, “testinic acid,„ and humic acid samples were thus analyzed. The present method is recommended for the simultaneous determination of catechins and anthocyanogens in any tanninogen-containing materials.