Olfactory Detection Thresholds for Smoke Taint in Red Wine
Miguel Pedroza,* Deborah Parker Wong, and Derek
Sanchez
*California State University, Fresno, 2360 E. Barstow Ave M/S
VR89, Fresno, CA, 93740 (miguelp@csufresno.edu)
This work determined the olfactory detection thresholds of a mixture of volatile phenols (VP) representative of wildfire smoke exposure in red wines, namely guaiacol, 4-methylguaiacol, 4-ethylguaiacol, 4-ethylphenol, m-cresol, p-cresol, and syringol. The concentrations of the individual VPs included in the mixture were obtained from a literature review of red wines made with grapes that had been exposed to wildfire smoke. Threshold testing was conducted following the ASTM-E679 method, using an unoaked Cabernet Sauvignon wine spiked with increasing levels of the VP mixture and a panel of 25 consumers. The Best Estimate Threshold (BET) values for the VP mixture were ~30% of the average concentration of VPs found in red wines produced with grapes exposed to wildfire smoke. For some compounds such as guaiacol, the BET values were ~16% of the threshold reported in the literature. Our results highlight how olfactory detection threshold concentrations are significantly decreased by the synergistic effect of multiple volatile compounds in the wine matrix. For winegrowers and winemakers, our results suggest that consumers will be able to detect smoke-exposed wines at lower concentrations than currently reported in the literature.
Funding Support: CSU-Agricultural Research Institute Grant 22-02-115; Oak Solutions Group, Inc.; E&J Gallo Winery
