Why is “smoke taint” a problem? Don’t they clean the grapes?
Hello there! I'm Dr. Vinifera, but you can call me Vinny. Ask me your toughest wine questions, from the fine points of etiquette to the science of winemaking. And don't worry, I'm no wine snob—you can also ask me those "dumb questions" you're too embarrased to ask your wine geek friends! I hope you find my answers educational, empowering and even amusing. And don't forget to check out my most asked questions and my full archives for all my Q&A classics.
Dear Dr. Vinny,
Why is “smoke taint” a problem? Don’t they clean the grapes?
—Lynda, Elk Grove, Calif.
Dear Lynda,
Good question, but smoke taint is a little more complicated than just rinsing ash off of wine grapes. Burning wood releases compounds called volatile phenols, which actually permeate the waxy skins of grapes and bond to sugars to form molecules called glycosides. Those aren’t something that can be rinsed off.
Smoke taint is very complicated, and difficult to predict. White wines are made from juice that doesn’t get much contact with the grapes’ skins, so those wines are less susceptible to smoke taint. But red wines go through the maceration process (when the skins and solids of the crushed grapes are steeped in the juice to introduce more color, structure, flavor and aromas to the wine), so those wines are much more sensitive to smoke taint.
There have been studies looking at washing smoke-affected grapes, trying cold water, warm water and water mixed with ethanol. None of those post-exposure treatments appeared to reduce the effects, and some actually seemed to amplify the taint.
I know it might seem strange, but grapes aren’t typically washed before they are turned into wine. Winemakers do their best to pick grapes at the perfect level of flavor, ripeness and acidity. Washing them would risk dilution as well as the loss of indigenous yeasts that the winemaker might be relying on for the fermentation process. Wine grapes also grow in tightly packed clusters (unlike table grapes), so they’re more prone to mold and mildew when moisture is introduced.
There has, however, been some promising research on protecting grapes from smoke taint before it happens. There’s always new science to come, but for now, you should check out our complete guide, “Understanding Smoke Taint,” for more.
—Dr. Vinny
