Phenolic compounds occur in all fruits as a diverse group of secondary meta
bolites. Hence, they are a component of the human diet although data for di
etary intakes and metabolic fate are limited. Their role in oxidation proce
sses, as either antioxidants or substrates in browning reactions, is examin
ed. They are characterised by high chemical reactivity and this complicates
their analysis. (C) 1999 Elsevier Science Ltd. All rights reserved.