Food browning catechin

Bradshaw MP, Prenzler PD and Scollary GR. 2001. Ascorbic acid-induced browning of (-l-)-catechin in a model wine system. J Agric Food Chem 49(2) 934—939. 

Richard-Forget, F.C. and GauUlard, F.A. Oxidation of chlorogenic acid, catechins, and 4-methylcatechol in model solutions hy combinations of pear Pyrus communis Cv. Williams) polyphenol oxidase and peroxidase A possible involvement of peroxidase in enzymatic browning, J. Agric. Food Chem., 45, 2472, 1997. 

Phenolic compounds are also involved in the enzymatic and non-enzymatic browning of food products. The occurrence of browning reactions is often disadvantageous in the majority of fruit processing operations. Chlorogenic acid and catechin serve as the principal substrates for the phenolase complex that is responsible for the enzymic browning exhibited by many fruits and vegetables. 

Catechins, or flavan-3-ols, are present mainly in woody tissues. Among common foods, tea leaves contain at least six catechins representing about 25% of the dry weight of tea leaves. Tea catechins are excellent substrates for the catechol oxidase that is present in tea leaves and participates in the conversion of green tea to black tea. The reddish brown color of tea brew is due to a mixture of... 

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