A similar result was observed for wine colour density (WCD). Anthocyanins are the pigments that give red grapes and wine their colour (Ribéreau-Gayon, 1982), thus higher wine colour density (WCD) is generally observed in wines made from fruit containing greater anthocyanin concentrations, although this is not always the case. As expected, the two wines made from fruit containing high concentrations of anthocyanins had significantly higher WCD than wines made from fruit containing low anthocyanin concentrations. This difference in WCD was maintained with wine aging despite a decrease in WCD over time for all wines. The decrease in WCD observed with aging reflects the decrease in the concentration of unstable monomeric anthocyanins that are initially responsible for wine colour (Ribéreau-Gayon, 1982; Somers, 1971). The low WCD observed at bottling is most likely due to sulphur and acid adjustment at the time of bottling, which have a bleaching effect.