Colour and antioxidant properties of malvidin-3-glucoside and Vitisin A

This study presents findings from comparing the properties of anthocyanin pigments: i. malvidin-3-glucoside (Mal-3-G), the most significant anthocyanin present in young red wine; ii. Vitisin A (5-carboxypyranomalvidin-3-glucoside), a major product from a reaction induced in red wine between Mal-3-G and pyruvic acid during its ageing. These pigments were determined and compared to the absorption spectrum in 200–770 nm at various pH values, such results including the ability of cation Al3+ to change the values of absorbance. Changes in the colour parameters L* a* b* were determined in the CIELAB colour space of Mal-3-G and Vitisin A in relation to pH and the addition of AlCl3. Both coloured compounds were investigated for their resistance to discoloration by sulphur dioxide. Total antioxidant activity was evaluated by two methods (FRAP, DPPH), and the values were compared to other phenols

Study of Sangiovese Wines Pigment Profile by UHPLC-MS/MS

The metabolic pigment composition of Sangiovese wines produced from grapes harvested at 20 different vineyards in Montalcino over three consecutive years (2008-2010) on a semi-industrial scale and of 55 commercial Brunello di Montalcino wines (2004-2007) was studied, using a targeted method capable of analyzing 90 pigments in an 11 min UHPLCMS/MS chromatographic run. Interesting correlations were shown between various pigments formed during wine aging and those present in Sangiovese grapes. Vitisin B-like pigment and vitisin A-like pigment concentrations would seem to have a good correlation with ethyl-linked and direct-linked flavanol-anthocyanin concentrations, respectively. Moreover, the anthocyanic pattern recognition, genetically controlled by the plant variety, was shown to be inherited by the pigments formed during wine aging