Listen: Wine Country Wildfires Leave Questions for Vintners


By Amy Quinton and Andy Fell
Photographs by Joe Proudman on October 8, 2018 in Food & Agriculture



Seeking Solutions to Smoke Taint in Wine

A year ago this week, a series of fires broke out in Napa, Sonoma, and Mendocino counties. The area is one of California’s best-known wine growing regions. While 90 percent of the grapes in Napa County had been harvested, a few vineyards still had grapes on the vine, including at the University of California, Davis’s experimental station in Oakville.

(Photo courtesy Anita Oberholster)

Harvesting Cabernet Sauvignon grapes at Oakville Experimental Station under smoky conditions in 2017. From left to right are Ph.D. student Raul Girardello, M.S. student Arran Rumbaugh and Anita Oberholster, cooperative extension specialist in the Department of Viticulture and Enology.

Smoke from nearby wildfires can ruin the quality of wine. Anita Oberholster, a viticulture and enology extension specialist at UC Davis has been researching so-called smoke taint, in hopes of finding the best ways of treating the wine to mitigate the effects.

Raul Giradello, a PhD student in horticulture and agronomy, smells Cabernet Sauvignon grapes at the UC Davis Teaching and Research Winery at the Robert Mondavi Institute for Food and Wine on Wednesday, Nov. 8, 2017​

Volatile phenols from smoke can permeate the skins of the grape. It can lead to wine that at its worst, can have a smell and flavor similar to wet cigar or cigarette butts. The timing of the grapevine smoke exposure influences the severity of the taint in wine. Grapes are most susceptible to smoke taint from after veraison (color change for red grapes) to harvest. Oberholster has produced wine from six tons of smoke-exposed grapes from last year’s wildfires.

Cabernet Sauvignon grape skins that were exposed to smoke are being processed to make wine.

Anita Oberholster uses a pipette to examine smoke-exposed wine that’s been sitting in fermentation tanks. (Joe Proudman/UC Davis)
A sample of wine from a fermentation tank at the UC Davis winery. Smoke taint can be noticed during fermentation, before bottling. (Joe Proudman/UC Davis)

A sample of Cabernet Sauvignon grapes is taken from fermentation tanks. Six tons of smoke-exposed grapes from the 2017 Northern California wildfires were made into wine at UC Davis.​

Andy Fell and Amy Quinton talked to Oberholster to find out more about her research in a special extended edition of Three Minute Egghead podcast.

Media contact: Amy Quinton, UC Davis News and Media Relations, 530-752-9843,



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