Smoke Taint in the Okanagan Valley: A Summary
Posted by The Team at Le Vieux Pin and LaStella Wineries on 26th Apr 2023
Smoke and its influence on wine has become a trending topic, in the Okanagan Valley, and around the world as forest fires become more and more prevalent. We have made some notes on the research being done here in the Okanagan and abroad to help you understand the not-so-basic way that smoke taint occurs; and to share our own philosophies regarding our vintage-specific experiences.
Direct smoke on the grapes themselves is the main contributor to the smoke taint we perceive. Conversely, smoke on the vine leaves is not considered a major way the smoke taint enters the plant or grape clusters.
The grapes are most vulnerable to smoke taint when they are green, and during veraison (the onset of berry ripening). They are less impacted once they are fully developed, near the end of ripening. Further, faint smoke in the atmosphere doesn't cause taint, whereas fires near by the vineyards do. In other words, like hail, smoke taint is very localized and can affect two vineyards close to each other differently.
Further, the grape skins hold 50% of the volatile phenols. Longer macerations and skin contact transfers the smoke taint from the skins to the juice. This is why smoke taint can be less noticeable or not noticeable at all in white wines and rosé compared to reds.
In wine, the characteristics of smoke taint can be described by the terms ashy, smoky, burnt, sometimes medicinal, that can be on the nose and linger on the palate. This smoke taint is made of measurable volatile phenols (glycosides), primarily guaiacol and cresol. Guaiacol is a key indicator of smoke taint and accumulates in grapes in a bound form. Smoke taint, occurs when these bound molecules are unbonded and released. Low levels of guaiacol contribute to aromas associated with new barrel aged complexity.
What we know from these smoky vintages (most recently 2021) is that you can open a bottle one day experiencing the smoky flavours and you can open the same wine again weeks or months later and it won't show smoky characteristics at all! It is our modern smoke roulette. There is no guarantee that the smoky flavours will not appear again in the bottle later due to how these molecules become bonded and unbonded. Ways to remedy smoke tainted wine fully is not readily available although some believe reverse osmosis can help but it also strips a wine’s complexity in the process.
If you are noticing some smokiness in the wine, try decanting the wine aggressively to help the smoky molecules become unbonded and this can help dissipate that flavour. This will not remove all of the smoky flavour but can help bring out more of the complexity behind the smoke.