Characterization of the Key Aroma Compounds in a Commercial Fino and a Commercial Pedro Ximénez Sherry Wine by Application of the Sensomics Approach

Following the sensomics approach, the key aroma compounds of a commercial Fino and Pedro Ximénez sherry were identified, quantitated, and validated through recombination experiments. In Fino sherry, 31 compounds were determined in concentrations above their odor detection thresholds, with the fruity/green smelling 1,1-diethoxyethane displaying the highest odor activity value ((OAV); the ratio of the concentration to the odor threshold) of 8970, followed by ethyl (2S,3S)-hydroxy-3-methylpentanoate (853) and 2- and 3-methylbutanal (448). In the Pedro Ximénez sherry, 23 compounds were present in concentrations exceeding their odor thresholds, and the malty smelling 2- and 3-methylbutanal were found with the highest OAV (1006), followed by 1,1-diethoxyethane (808) and methylpropanal (561). The results were compared to those characterized previously by us in an Amontillado sherry revealing that in all three sherry wines, 1,1-diethoxyethane, 2- and 3-methylbutanal, methylpropanal, ethanol, ethyl (2S,3S)-2-hydroxy-3-methylpentanoate, acetaldehyde, and 3-(methylthio)propanal, as well as the fruity-smelling ethyl 2-methylbutanoate, ethyl hexanoate, ethyl octanoate, and ethyl 3-methylbutanoate ranked among the 15 odorants with the highest OAVs. But, although most odorants were identical in the three sherries, their amounts differed significantly. The results are discussed considering the different winemaking processes and the different aroma profiles.