Changes in anthocyanins and color characteristics of Pinot noir wines during different vinification processes

Simple and polymeric anthocyanins of Pinot noir wines produced by different vinification processes were monitored by high-performance liquid chromatography (HPLC) from the onset of fermentation to bottling. Color characteristics were determined by. tristimulus measurement using a spectro-photometer with a color determination and match program. Up to 12 individual polymeric anthocyanins were found. Extraction of monomeric anthocyanins was increased with higher fermentation temperature, but anthocyanin concentration declined gradually after fermentation. In all wines, the dominant type of anthocyanin was malvidin 3-glucoside. In contrast, the content of polymeric anthocyanins increased during fermentation and thereafter, and reached the highest concentrations at bottling. Fermentation temperature was a critical factor for formation of polymeric anthocyanins. The presence of total or individual polymeric anthocyanins was directly related to wine color intensity, and all the polymeric anthocyanins were important to wine color.