Phenolic Diglycoside Biomarkers: Assessing 2020 Wildfire Smoke Impacts on Oregon Pinot noir Wines Alongside Sensory and Marketplace Data

Abstract This study presents the first AVA-resolved retrospective assessment of wildfire smoke impacts on 2020 Oregon Willamette Valley Pinot noir by merging phenolic diglycoside (PDG) biomarker concentrations with sensory appraisals and marketplace performance. Analysis of 90 commercial wines representing all 12 Willamette Valley AVAs revealed that most lots lacked molecular evidence of substantial wildfire smoke exposure. There were some wines identified that exhibited PDG concentrations indicative of a slight to moderate smoke impact. These findings demonstrate that smoke exposure during the 2020 harvest was heterogeneous across vineyards rather than a region-wide phenomenon. Combined with sensory observations and marketplace performance, summed PDG concentrations provide a more reliable retrospective indicator of vineyard smoke exposure than volatile phenols (VPs) alone. The analytical framework created in this study provides a transferable approach for evaluating wildfire smoke impacts, guiding vineyard and winery decision-making, and assessing future wildfire risk in premium wine regions.