Volatile and phenolic composition of red wines subjected to aging in oak cask of different toast degree during two periods of time

- Wines were aged in barrels with different toast degree during 1.5 and 3 months.
- Fingerprint were obtained by constructing aromatic series with aroma compounds.
- Chemometric analysis permits the differentiation of the wines.
- Total phenolic compounds increased during aging highlighting flavanols and flavonols families.
- Wines aged during three months were the best valued by a tasting panel.

Volatile aroma compounds of Fetească neagră wines, aged for 1.5 and 3 months in oak barrels with different toast degree, have been analyzed using stir bars sorptive extraction and gas chromatography coupled to mass spectrometry. Principal components analysis of the volatile aroma permits wine differentiation according to the toast degree of the barrels used and also according to aging time. Wine fingerprints were obtained using the aromatic series. Cluster analysis showed that the differences among wines due to the toast degree of the barrels become progressively larger with aging time. Regarding phenolic families, flavonols and flavanols increased with aging time, whereas polymeric compounds decreased due to the precipitation phenomenon. The wines aged in light toast barrels were those with the higher phenolic concentration. The toast degree and the aging time influence significantly the aroma and phenolic composition of the aged wines. Sensory analysis indicated that wines aged for 3 months show the best valuation, highlighting those aged in barrels with medium toast degree. All these changes must be taken into account by the winemaker in order to produce wine with the best quality.