Development and evaluation of a vineyard-based strategy to mitigate smoke-taint in wine grapes.

Smoke-taint is a wine defect that may occur when ripening grape crops absorb volatile phenols (VPs), compounds associated with the negative sensory attributes of smoke-taint, due to exposure of the grapes to wildfire smoke. This study examined potential methods to reduce the impact that smoke-exposure has on wine grapes. Specifically, agricultural sprays normally used to protect grapes from fungal pathogens and a spray used to prevent cracking in soft-fleshed fruits were assessed for their capacity to inhibit increases in VP concentrations in wine grapes following on-vine smoke-exposure. The results indicated that an artificial grape cuticle applied one week before exposure to simulated forest fire smoke (at 1-2 weeks after veraison) can significantly hinder an increase in VP concentrations in smoke-exposed grapes at commercial maturity. This reduction in VP concentrations may mitigate the crop losses experienced globally by the wine industry due to exposure of grapes on-vine (at key phenological stages) to wildfire smoke.