The ability of isoflavonoids to augment the color of muscadine grape juice was first evaluated using commercial standards of formononetin and biochanin A and then with extracts of red clover all dissolved in 100% ethanol. Copigments were evaluated at varying concentrations by adding isoflavonoid extracts to muscadine grape juice (diluted 1:4 with 0.5 M citric acid buffer at pH 3.5 ) and compared to an ethanol blank likewise prepared. Molar ratios between anthocyanin aglycones and the isoflavonoids were determined using the average molecular weights for the anthocyanins and isoflavonoids present.