Analytical study of aromatic series in sherry wines subjected to biological aging.

The odor activity values (OAVs) for 49 aroma compounds in commercial sherry pale white wines were grouped, according to the similarity of their aroma descriptors, into nine odor classes with a view to establishing the aroma profile for this type of wine. The results revealed the profile to be largely comprised of the series named "fruity" and "balsamic", mainly as a result of the 1,1-diethoxyethane content in the wines. The same series were calculated from the OAVs obtained in biological aging experiments, carried out with selected strains of the flor yeasts Saccharomyces cerevisiae and Saccharomyces bayanus, over a period of 9 months. Based on the aroma profiles thus obtained, after 6 months of aging the latter race yielded OAVs for the fruity and balsamic series not significantly different (p < 0.05) from those for commercial wines aged for 5 years. However, except for the series named "solvent", all others exhibited lower values in the experiments carried out with selected strains than in the commercial wines, mainly as a result of the absence of contact with wood of the former wines. Taking into account the results, the biological aging of this type of sherry wine can be shortened by subjecting it to controlled aging with selected yeast strains in a first stage and subsequently allowing it to stand in wood casks in a second stage.