Occurrence of anthocyanin-derived pigments in red wines

Several anthocyanin-derived pigments that showed UV-visible spectra different from those of the original grape anthocyanins were detected by HPLC-DAD analysis in 1-year-old bottled Port wines from the Douro region. Among these, three malvidin 3-glucoside derived pigments were detected in large amounts, representing similar to 60% of the total anthocyanidin monoglucosides content. These pigments were isolated, purified, and identified by LSI-MS and NMR (H-1, DQF-COSY, ROESY, HSQC, and HMBC) techniques. The major pigment is malvidin 3-glucoside pyruvic adduct, previously characterized, and the other two corresponded to its respective acetyl and coumaroyl glucoside derivatives. The latter is reported for the first time in red wines.