Vitaglione P., Donnarumma G., Napolitano A., Galvano F., Gallo A., Scalfi L., Fogliano V. (2007) Protocatechuic acid is the major human metabolite of cyanidin-glucosides. J Nutr 137:2043-8 PubMed (17709440)

Compound Mean content
Cyanidin 3-O-glucoside 43 mg/L
Cyanidin 3-O-(6''-malonyl-glucoside) 28 mg/L