| Title: | Large-Scale Reassessment of In-Vineyard Smoke-Taint Grapevine Protection Strategies and the Development of Predictive Off-Vine Models |
| Author(s): | Favell JW; Fordwour OB; Morgan SC; Zigg I; Zandberg WF; |
| Address: | "Department of Chemistry, The University of British Columbia, 3247 University Way, Kelowna, BC V1V 1V7, Canada. Department of Biology, The University of British Columbia, 1177 Research Road, Kelowna, BC V1V 1V7, Canada" |
| DOI: | 10.3390/molecules26144311 |
| ISSN/ISBN: | 1420-3049 (Electronic) 1420-3049 (Linking) |
| Abstract: | "Smoke taint in wine is thought to be caused by smoke-derived volatile phenols (VPs) that are absorbed into grape tissues, trapped as conjugates that are imperceptible by smell, and subsequently released into wines as their free odor-active forms via metabolism by yeasts during fermentation. Blocking VP uptake into grapes would, therefore, be an effective way for vineyards to protect ripening grape crops exposed to smoke. Here, we re-evaluated a biofilm that had previously shown promise in pilot studies in reducing levels of smoke-derived VPs. A suite of nine free and acid-labile VPs were quantitated in Pinot Noir grapes that had been exposed to smoke after being coated with the biofilm one, seven or 14 days earlier. In contrast with earlier studies, our results demonstrated that in all cases, the biofilm treatments led to increased concentrations of both free and total VPs in smoke-exposed grapes, with earlier applications elevating concentrations of some VPs more than the later time points. Tracking VP concentrations through the grape ripening process demonstrated that some (phenol, p/m-cresol, and guaiacol) were not entirely sequestered in grapes as acid-labile conjugates, suggesting the presence of VP storage forms beyond simple glycosides. Free VPs in grapes, though a minor portion of the total, most clearly correlated with concentrations present in the resulting wines. Finally, red table grapes, available year round, were observed to replicate the effects of the biofilm treatments and were capable of transforming most VPs into acid-labile conjugates in under 24 h, indicating that they might be an effective model for rapidly assessing smoke-taint prophylactic products in the laboratory" |
| Keywords: | *Farms *Smoke Vitis/*growth & development *Volatile Organic Compounds crop protection fermentation gas chromatography-mass spectrometry glycosidase glycosides grapes smoke taint volatile phenols wine yeast; |
| Notes: | "MedlineFavell, James W Fordwour, Osei B Morgan, Sydney C Zigg, Ieva Zandberg, Wesley F eng 35246/Canada Foundation for Innovation/ Undergraduate Student Research Award/Natural Sciences and Engineering Research Council of Canada/ Eminence Program/University of British Columbia, Okanagan Campus/ project 25246/British Columbia Knowledge Development Fund/ Switzerland 2021/07/25 Molecules. 2021 Jul 16; 26(14):4311. doi: 10.3390/molecules26144311" |
