H2O2-mediated pigment decay in strawberry as a model system for studying color alterations in processed plant foods

Phenolic and pigment (anthocyanin) stability in processing-ripe strawberries in response to aging under mildly oxidizing conditions, provoked by exogenous application of H2O2, has been studied to design a simplified model system to study color alterations (pigment decay) that occur in strawberry-derived foods during processing and storage. The results showed that phenolic metabolism in strawberry slices during aging under mildly oxidizing conditions may be either oxidative (independent of exogenous H2O2) or peroxidative (dependent on exogenous H2O2), and that feeding strawberry slices with H2O2 stimulates the oxidative phenomena which take place in their absence, such as the processes of anthocyanin and catechin degradation. The results also showed that because both (+)-catechin and anthocyanin levels in strawberry slices fall as H2O2 increases, both p-hydroxybenzoic acid and brown polymeric compounds are formed. Comparison of these results with controls in the absence of H2O2 suggests that peroxidase may play an important role in catechin consumption and in anthocyanin degradation and brown polymer formation during the aging of strawberry slices under mildly oxidizing conditions.