The influence of pectolytic enzyme addition and prefermentative mash heating during the winemaking process on the phenolic composition of Okuzgozu red wine

► Highest concentration of total phenolics and total flavan-3-ols was found in the mash heated wines. ► Enzyme treated wines contained less phenolic acids than those of control and mash heated wines. ► Extraction of monomeric anthocyanins was not increased with enzyme addition. ► All phenolic acids, but gallic acid, decreased with winemaking process and ageing. ► Catechin and epicatechin decreased during winemaking process and ageing.