Determination of free radical scavenging activity of anthocyanins using diphenylpicrylhydrazyl radical

It has been demonstrated that hydrochloric acid reacts with the diphenylpicrylhydrazyl radical, which leads to a likely overestimation of the antioxidant capacity of anthocyanin extracts obtained by acidifying the extractants with hydrochloric acid. Therefore, during the extraction process it is recommended to replace hydrochloric acid with sulfuric acid.