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

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.     

Evolution of polyphenolic compounds in red wine from Cabernet Sauvignon grapes processed by pulsed electric fields during aging in bottle

The evolution of the Folin–Ciocalteu index, colour intensity and the principal individual polyphenols throughout 12 months of aging in bottles of red wine from Cabernet Sauvignon grapes treated and untreated by pulsed electric fields (PEF) have been compared. PEF technology allowed bottling of wines with higher Folin–Ciocalteu index, colour intensity and individual polyphenols concentrations using a shorter maceration time. For both wines, aging did not affect the colour intensity, whereas the Folin–Ciocalteu index decreased. The evolution of the principal individual polyphenols during the 12 months of storage followed a similar pattern in both wines. At the end of aging, there were no significant differences observed in the content of monomeric anthocyanins between both wines, however, the content of flavan-3-ols, flavonols and hydroxycinnamic acids and derivatives was higher in PEF treated wine. These results indicate that PEF could be a suitable technology for obtaining wines with higher phenolic content or reducing the maceration time during vinification.     

赤霞珠、蛇龙珠和玫瑰香葡萄酒芳香性成分的差异性研究

芳香类物质种类及含量的差异是决定葡萄酒风味的重要因素。本文对赤霞珠、蛇龙珠和玫瑰香葡萄酒的芳香性成分进行探讨分析。结果表明,3种葡萄酒中3-甲基-1-丁醇的含量最高,相对含量分别为20.61%、21.00%和15.54%;次之为丁二酸单乙酯,含量分别为17.90%、8.94%和16.55%;再次为乳酸乙酯,含量分别为12.36%、17.01%和12.06%。赤霞珠干红葡萄酒中特有的检出成分为乙酸异戊酯和丙酸;玫瑰香葡萄酒中特有的检出成分为3-乙氧基丙醇。蛇龙珠葡萄酒中没有检出1-丁醇、4-酮基-戊酸乙酯和癸酸乙酯,赤霞珠和玫瑰香葡萄酒中均有上述成分;玫瑰香葡萄酒中未检测到(顺)3-己烯-1-醇和糠醇。     

Effect of light and temperature on 3-alkyl-2-methoxypyrazine concentration and other impact odourants of Riesling and Cabernet Franc wine during bottle ageing

3-Alkyl-2-methoxypyrazines (MPs) are grape- and insect-derived odour-active compounds responsible for green and vegetative perceptions in wine, and at elevated concentrations are detrimental to wine quality. We examined the influence of light and temperature during cellaring on MPs and other impact odourants. Riesling and Cabernet Franc wines were supplemented with 30 ng/L of each of 3-isopropyl-2-methoxypyrazine (IPMP), 3-s-butyl-2-methoxypyrazine (SBMP) and 3-isobutyl-2-methoxypyrazine (IBMP), and stored under one of the following conditions: (i) at ambient temperature (22 °C) under fluorescent lighting, (ii) in the dark at ambient temperature, or (iii) in the dark at cellar temperature (12 °C). Additionally, for the light condition, wine was stored in clear, green or amber bottles.     

Time course of the colour of young red wines from Vitis vinifera L. during ageing in bottle

The colour characteristics of red wines from Vitis vinifera L. cv Tempranillo, Graciano and Cabernet Sauvignon (vintage 2000) from Navarra (Spain), was studied during 26 months of ageing in bottle through the evaluation of the wine visible spectrum and of several colorimetric indices (colour intensity, %red, %yellow, %blue, %dA and tint) and CIELAB variables (L*, C*, h, a* and b*). During ageing in bottle, the spectrum of Tempranillo wine (pH 4.3) mainly changed in the absorbance range between 420 and 500 nm, whereas Graciano (pH 3.5) and Cabernet Sauvignon (pH 3.6) wines registered a decrease in absorbance in the interval between 500 and 560 nm. The time course of the different wine colour parameters was found to fit either a second‐order polynomium or a linear model, depending on the grape variety employed. CIELAB variables could be described in terms of their colorimetric index counterparts, showing b* and h relative greater errors. Although the wine total chromatic changes in CIELAB units registered after 26 months of ageing in bottle indicated changes perceivable by the human eye (ΔE* ≥ 2.7) for the three varieties studied, Graciano and Cabernet Sauvignon wines showed a more balanced colour evolution than Tempranillo wine.     

Effect of irrigation on changes in the anthocyanin composition of the skin of cv Tempranillo (Vitis vinifera L) grape berries during ripening

The impact of water availability on the yield and on the chemical composition in the skins of cv Tempranillo grapes at different phases of berry growth was studied over a 2 year period by determining changes in berry weight, °Brix, titratable acidity, pH and different phenolic compounds. The evolution of phenolic compounds during berry growth followed similar patterns to those reported by previous investigators. Over the 2 year study, concentrations of total phenols and total tannins in the skins were always higher for the non-irrigated than for the irrigated vines, though the differences were not significant on some sampling dates. Total anthocyanin concentrations in 1992 were significantly higher in the non-irrigated than in the irrigated grapes, except at véraison and harvest. In contrast, in 1993, concentrations were higher in the non-irrigated grapes on the first three sampling dates and in the irrigated grapes on the last three sampling dates, but with significant differences only on day 136 after budbreak. In the first year, anthocyanin concentrations for the non-irrigated grapes were higher than for the irrigated grapes, except at harvest, though the differences at harvest were not significant. However, in the second year, concentrations in the berries from the irrigated vines were significantly higher on most sampling dates. In both years, concentrations of the five anthocyanins at harvest were higher for the irrigated treatment, the treatment that produced higher berry weights and crop yields. © 2001 Society of Chemical Industry