Browning phenomena in stored artichoke (Cynara scolymus L.) heads: enzymic or chemical reactions?

Data concerning phenolics and polyphenol oxidase in artichoke heads are presented. Biochemical changes at different physiological stages and after mechanical damage or chilling injuries, together with the characteristics of iron/phenolic complexes and the subcellular localization of polyphenol oxidase, are considered. Results lead to a proposed mechanism of browning phenomena in cold-stored, non-mechanically damaged, artichoke heads