Inside scientists’ mission to save America’s wine industry from climate change

ALPINE, Ore. — The U.S. West Coast produces over 90% of America’s wine, but the region is also prone to wildfires — a combustible combination that spelled disaster for the industry in 2020 and one that scientists are scrambling to neutralize.

Sample a good wine and you might get notes of oak or red fruit. But sip on wine made from grapes that were penetrated by smoke, and it could taste like someone dumped the contents of an ashtray into your glass.

Wine experts from three West Coast universities are working together to meet the threat, including developing spray coatings to protect grapes, pinpointing the elusive compounds that create that nasty ashy taste, and deploying smoke sensors to vineyards to better understand smoke behavior.

The U.S. government is funding their research with millions of dollars. Wineries are also taking steps to protect their product and brand.

The risk to America’s premier wine-making regions — where wildfires caused billions of dollars in losses in 2020 — is growing, with climate change deepening drought and overgrown forests becoming tinderboxes. According to the U.S. Department of Agriculture, grapes are the highest-value crop in the United States, with 1 million acres (405,000 hectares) of grape-bearing land, 96% of it on the West Coast.

Winemakers around the world are already adapting to climate change, including by moving their vineyards to cooler zones and planting varieties that do better in drought and heat. Wildfires pose an additional and more immediate risk being tackled by scientists from Oregon State University, Washington State University and the University of California, Davis.

“What’s at stake is the ability to continue to make wine in areas where smoke exposures might be more common,” said Tom Collins, a wine scientist at Washington State University.

Researcher Cole Cerrato recently stood in Oregon State University’s vineyard, nestled below forested hills near the village of Alpine, as he turned on a fan to push smoke from a Weber grill through a dryer vent hose. The smoke emerged onto a row of grapes enclosed in a quasi greenhouse made of taped-together plastic sheets.

Previously, grapes exposed to smoke in the MacGyvered setup were made into wine by Elizabeth Tomasino, an associate professor leading Oregon State’s efforts, and her researchers.

They found sulfur-containing compounds, thiophenols, in the smoke-impacted wine and determined they contributed to the ashy flavor, along with “volatile phenols,” which Australian researchers identified as factors more than a decade ago. Bush fires have long impacted Australia’s wine industry. Up in Washington state, Collins confirmed that the sulfur compounds were found in the wine that had been exposed to smoke in the Oregon vineyard but weren’t in samples that had no smoke exposure.

The scientists want to find out how thiophenols, which aren’t detectable in wildfire smoke, appear in smoke-impacted wine, and learn how to eliminate them.

“There’s still a lot of very interesting chemistry and very interesting research, to start looking more into these new compounds,” Cerrato said. “We just don’t have the answers yet.”