ABSTRACTSAn enzymatic system capable of degrading cyanidin‐3‐glucoside in the absence of phenols is present in the skin of sweet cherries; contrarily, the pulp homogenate degraded the anthocyanin only in the presence of phenols. The degradation of this pigment as a function of pH was studied for two polyphenol oxidases isolated from the fruit pulp on DEAE‐cellulose with chlorogenic acid, D (+) catechine and pyrocatechol substrates. The decoloration was influenced by the anthocyanin structure at different pH and by the nature of the quinone obtained by enzymatic oxidation. The anhydrobase appeared to be the form of the anthocyanin most susceptible to oxidation. The degradation occurred according to the oxidation kinetics of the phenol substrate and was inhibited by ascorbic acid, indicating that the quinone's degradation of the anthocyanin occurred by a consecutive‐type me
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