Terroir is a funny thing. In the Mediterranean Basin, the pervasive thickets of thyme, lavender, kermis oak, rosemary, and other shrubs are collectively called garrigue, and are known to impart an earthy or herbal flavor to wines produced nearby.
In California, however, smoky notes may be on the horizon for the state's winemakers.
Raging wildfires—which are especially common in California this time of year, and aided no doubt by widespread drought—could have a lasting impact on wines made in the region, even if the vineyards themselves never see so much as a match flame. The state has already seen 1,500 more wildfires this season than usual.
One Sonoma winemaker told the Guardian, "It's a really big concern for a lot of these vineyards who are near fires and all that smoke because for red grapes, where the skin is still used in the winemaking process, that smoke could potentially infuse and create abnormal flavors."
Not just potentially—it has in the past. In 2008, smoke from forest fires blanketed California's Anderson Valley, imbuing the grapes grown there with "smoke taint" that ended up overwhelming all the other notes in the bottle a couple years later.
While the chemistry of smoke taint—a.k.a. the "wet ashtray" flavor—isn't well understood, vintners believe that a compound called guaiacol is the reason for it. An Australian report on smoke taint noted, "Wines made from grapes exposed to smoke during sensitive growth stages can exhibit aromas and flavors resembling smoked meat, disinfectant, leather, salami, and ashtrays."
Even for Islay scotch lovers, that's not a good thing.
According to a 2010 report by the Wall Street Journal, one vintner used fish bladder-derived isinglass to fine his wine, but was unsuccessful in removing the taint. Other winemakers tried egg whites and milk byproducts to no avail. After a highly successful vintage the year prior, many winemakers were forced to release only small quantities of their wine, if any at all.
One winemaker who tried everything possible to remove the taint told the paper, "I still smell smoke. It's like a scar."
Perhaps with memories of that scar in mind, this year winemakers have taken the precaution of sending grape samples to laboratories for testing ahead of the harvest season.
California's wine industry has already been pinched by the drought, withering vineyard yields in the process. While weather conditions have kept the smoke away from many vineyards so far, the winds could change at any time, and winemakers will be watching them with bated breath.