Comparison of the Aromas of Oak- and Glass-Aged Wines

Abstract

Commercially produced Cabernet Sauvignon wine was aged for 338 days in 228 L (60 gal) American (Missouri) and French (Nevers) oak barrels, which had been coopered by the same methods. The same wine was stored in five-gallon glass carboys which were held under identical storage conditions to serve as the glass-aged control. By difference tests, the wines aged in French and American oak barrels were not found to differ significantly, although both were highly significantly different from the glass-aged wine (p < 0.001). The lack of difference may be attributed in part to the strong varietal character of the base wine, which masked the oak flavor differences. Additionally, since the barrels from France and the U.S. were coopered by identical techniques, differences between the barrels were minimized. Since the two oak-aged wines could not be differentiated, the French oak sample was arbitrarily chosen to profile with the control to evaluate the effects of barrel aging. To quantify differences between the wine aromas, trained judges developed descriptors which were defined by reference standards. By this descriptive analysis, two major differences between the glass- and oak-aged wines were observed. In the oak-aged wine, the intensity of the spicy, vanilla, and oak blend attributes increased, probably describing the change in the wine aroma due to the extraction of volatile phenolic compounds, such as vanillin and eugenol, from the barrels. With oak-aging, a dramatic decrease in the intensity of the vegetative (green bean/green chiles) note occurred. Although the total aroma intensities of the wines were similar, it can only be speculated that this decrease was the result of more rapid degradation during barrel aging of the compound(s) responsible for the green bean/green chiles aroma rather than masking by the aromas of volatiles extracted from oak.