The sensory experience of wine aroma is challenging to study. Given the presence of numerous and trace level volatiles, the subtle aroma nuances involved, as well as the complexity of human odour processing, the contribution of individual compounds and mixtures can be difficult to determine. In white wines, the volatile compounds eliciting stone fruit aromas are not well understood.
In this work, factorial designs were used with odorant compounds added to a model wine and evaluated by quantitative descriptive sensory analysis. In model wines of the Viognier type, it was confirmed that several monoterpenes conferred stone fruit, apricot and peach attributes, which were strongly cancelled out by aldehydes that confer cardboard odors. It is important to note that the lactones enhance the apricot aroma when combined with the monoterpenes. For the model Australian Chardonnay wine that had not been put in wood, aliphatic ethyl esters, particularly ethyl octanoate, were found to be crucial to the peach aroma. Fatty acids strongly cancel out the peach attribute and produce cheesy odors.
The apricot and peach aromas in Viognier and Chardonnay, although perceptually similar, were caused by different families of chemical compounds: grape-derived monoterpenes with lactones and yeast-derived fatty acid ethyl esters, respectively.
Once the compounds responsible for apricot and peach aromas in white wine are confirmed, there is the possibility of modifying their concentration through specific viticultural and oenological practices
Reference Article
D. Espinase Nandorfy, T. Siebert, F. Watson, R. Keast, I.L. Francis; Understanding the interactive effects of volatile compounds contributing to ‘stone fruit’ aroma nuances in white wines; ASVO, Volume28, Issue3, July 2022, Pages 424-438; https://doi.org/10.1111/ajgw.12540
