Effect of the modifier (Graciano vs. Cabernet sauvignon) on blends of Tempranillo wine during ageing in the bottle. II. Colour and overall appreciation

Abstract

The effect of Graciano (GRA) (Spanish valuable variety of limited production) vs. Cabernet Sauvignon (CS) (world-wide known French variety) on the colour of wines from Tempranillo (TEM-base wine) (largely cultivated Spanish variety), was studied in wine blends prepared with 25% and 10% (v/v) of each modifier after 4, 6, 9, 16.5 and 23 months of ageing in the bottle. Although possessing pH values very similar to the base wine, the blends of TEM with GRA or CS wines showed chromatic changes (higher a*, C*, CI, %red and %dA, and lower h, %yellow, tint and L*) that were perceptible by the human eye, even when using as little as 10% of modifier wine. However, no differences in colour parameters were found between the TEM-GRA (90:10) and the TEM-CS (90:10) blends, and between the TEM-GRA (75:25) and the TEM-CS (75:25) ones, this being consistent with the results relating to the temporal evolution of anthocyanins and flavanols (Part I). Moreover, the results of the principal component analysis indicated that the degree of interrelation existing between the colour parameters and the phenolic components during ageing in the bottle was similar for the TEM-GRA and TEM-CS blends. From a practical point of view, the ANOVA analysis also demonstrated that for any of the modifier wines used, certain colour parameters and phenolic components allowed differentiation between the base wine and the 75:25 blends, whereas others allowed differentiation between the base wine and both the 90:10 and 75:25 blends, during the ageing period studied. Some similarities between GRA and CS as modifier wines of TEM blends were also found in terms of their organoleptic characteristics, also demonstrating that both varieties could render blended wines with better overall quality attributes than the base wine after 23 months of ageing in the bottle.