Moses Lake, WA 98837, USA

Researchers look for input for smoke exposure grant

Staff Writer

KENNEWICK — Like most people, wine growers don’t like wildfire smoke. In addition to the health issues that prolonged smoke exposure can have, wine growers don’t like it for another reason. Prolonged smoke exposure can adversely affect the flavor of wine, according to a wine researcher. So can short, high-intensity smoke exposure.

But there is one problem with smoke exposure in wine grapes: There are more questions about it than there are answers.

Tom Collins is a researcher from Washington State University who has been trying to answer some of the questions surrounding smoke exposure. He and researchers from the Oregon State University and University of California-Davis are collecting information from grape growers and winemakers about areas of smoke exposure that they would like to see studied. The goal of the researchers is to apply for a U.S. Department of Agriculture Specialty Crop Research Initiative grant this fall.

So far, two meetings for the wine industry on smoke exposure research have been held, in Oregon and California. The last meeting to be held will be Monday, March 2, at 1:15 p.m., during the Washington Winegrowers Association annual meeting at Three Rivers Convention Center in Kennewick. If they get the grant, the researchers hope to be able to combine their individual efforts, as well as hire more researchers to help study smoke exposure.

Smoke exposure can happen in wine grapes in a couple of different ways. Periods of prolonged low-intensity smoke, such as smoke that has drifted in from wildfires, and short but high-intensity smoke, such as from a fire that has burned up to the edge of a vineyard, can permeate the fruit and, sometimes, the vine. While the effect that the smoke has on the grapes can’t be seen, it can be tasted after the wine has fermented.

One of the problems with smoke exposure is that, so far, no one knows exactly how much smoke it takes to affect the grapes.

“It doesn’t always happen or it happens in different ways,” Collins said. “What we’re trying to understand is how much smoke does it take and for how long. Does it depend on what is burning?”

Another question that researchers would like to know is what compounds come from smoke exposure and what levels of those compounds affect the taste of the wine.

“There are some compounds that seem to be related to the problem,” Collins said. “They appear to be primarily in the skin.”

With what current information is known, growers can submit samples of grape skins for testing to see if they have smoke exposure. To avoid the foul smoke or ash taste in the finished wine, winemakers can remove the skins of the grapes. But that only works when making white wines. Skins are normally removed in white wines. Red wines, however, ferment with their skins. So skin removal is not an option. Having the fruit tested for smoke exposure prior to harvest allows growers to make the best decisions regarding their fruit.

“It may limit options for harvesting,” Collins said.

Australians discovered smoke exposure in wine grapes in the late 1990s and early 2000s. While they have done some research on the topic, Collins said that their research raised more questions than it has answered.

The first time the United States dealt with smoke exposure was with the 2008 vintage in California. Since then, the problem in the U.S. has become more widespread. In 2016, WSU began researching smoke exposure, followed by UC Davis and Oregon State University. The funding for the research has come from local and state sources.

The grant that Collins and the other researchers would like to get would allow them to work together on a multi-state project and hire more researchers.

The researchers are seeking input from growers and winemakers on what topics related to smoke exposure that they would like to see researched further. One of the things that has stood out in the meetings held in Oregon and California is the need for more tools to assess smoke exposure in the vineyard.

Until the researchers can get the grant, Collins said that they will continue to work on individual projects that answer some of the questions related to smoke exposure.

Rachal Pinkerton may be reached via email at