After wildfire smoke from Oregon and California lingered in the region for many days mid-September — and Walla Walla County reached an air quality index of over 400 — winemakers are adjusting their winemaking processes to try and avoid the impacts of smoke on their wine grapes.
Harvest is in full steam right now. Some local vineyards were able to sell the remainder of their grapes to wineries in areas like California and Oregon that were in closer proximity to the fire and smoke impacts.
Smoke influence in wine is difficult to pinpoint and can’t be determined simply by tasting a grape. It can show up in the fermentation process and even after being in the bottle a year or two.
Jason Fox, an assistant winemaker for Isenhower Cellars and co-owner of Lagana Cellars, is taking out all of the variables that could add a smoke flavor to the wine.
He said he would not add stems in the winemaking process to mitigate. Stems add tannin, typically giving wine more structure and spiciness.
He is also eliminating cold soaks from his process, where grapes usually sit in a bin wrapped, covered in CO2, not fermenting, to bring extra color before fermentation.
He is taking these processes out to eliminate any possible smoke influence in the grapes’ stems or skins if it existed.
He will use less new oak barrels because those barrels have similar compounds to smoke.
He said they did eight micro-fermentations for Isenhower Cellars, a process where they pick 15 grape clusters from varying rows on a lot in the vineyard, squish them in a bucket, and add yeast, let them ferment, add nutrients, and smell for smoke every day for a week.
This is not a typical process but helps winemakers know better what they are dealing with and how the real fermentation will go. If they get smoky smells, the fermentation will likely lead to that as well.
They did micro-fermentation on barbera, cabernet, cabernet franc and petit verdot grapes.
“So far we didn’t smell anything that was smoky,” he said.
They may send samples in March to a lab to confirm whether they have any smoke influence.
The smoke event in Walla Walla in September came at a peak time before or during harvest, Fox said.
“It depends what time of the year it’s happening,” he said. “If it’s in May, not a problem because the grapes are so small, they’re not really growing. If it happened now, it probably also wouldn’t be a problem because the vines aren’t actively growing and making sugar, they’re just finishing their ripening.”
Winemakers at Aluvé limited the amount of juice extracted by pressing at a lower pressure to extract less skin content to minimize the potential smoke impact on all of their white wines.
On the red wines, they shorten fermentation times by about 10-15%, or a couple of days, to prevent extracting as much potential smoke contamination from the grapes.
Because smoke primarily resides in the grapes’ skins, by minimizing the overall time on the skins and doing a soft press, you could reduce the extraction of smoke elements that might show up in the wine, JJ Menozzi, co-owner of Alluvé said.
He and his wife and co-owner, Kelly, also did micro-fermentation on petit verdot and another variety and did not smell any smoke.
He said he has gotten together with local winemakers who have dealt with smoke events before, and they can collaborate and learn from each other about the issue, since it's something he has never experienced.
Seven Hills Vineyard Manager Sadie Drury said she thinks there will still be many great wines made in 2020 regardless of what happened with the smoke.
“The quality of the fruit this year is really good,” she said.
Yields are down due to the fall frost from last year and spring rains, so the grapes’ quality is up, she said.
Additionally, the smoke may have aided in quality because the grapes hold onto their acids, the pH is lower in the grapes than normal, so the acidity can sometimes make the wines better.
She said she sent samples of cabernet sauvignon, cabernet franc, merlot, sangiovese, syrah and petit verdot to test for smoke.
“The results were generally pretty good, and so we think our fruit and vineyards fared really well,” she said.
This year she sold a bit more than half of her grapes to local winemakers and the other half to buyers in Woodinville and the Willamette Valley.
Because of the COVID-19 pandemic, she had grapes left to sell because wineries cut back on production. She received a lot of calls from wineries in California looking for fruit that wasn’t smoke impacted.
She said she sold the remainder of her fruit to Southern Oregon in mid-September.
Walla Walla was very far from where the fires were. The closer the fire, the more compounds that can land on the vines and be digested into the grapes, said Tim Donahue, director of winemaking and instructor of enology at Walla Walla Community College.
“Most of the smoke we had got blown out over the ocean where it sat for a while and then came back in,” he said. “That is one thing research has shown pretty clearly, the older the smoke is, the farther away it is, the less likely it is to really have significant influence.”
“So I am kind of hoping that some of the oils and other things that can really taste nasty sort of stayed out there and casually optimistic that we might be spared.”
He said he thinks there will be some influence here and there on some wines. Varieties such as petit verdot pick it up more than others.
It tends to be the one to show the most. Merlot is relatively resistant to smoke influence, and syrah already has many compounds in it. It’s natural to the grape, so it might not even be noticeable.
Smoke influence can add complexity and interest, Donahue said. It’s not always a bad thing and is not harmful to human health.
When the grape is on the vine during a smoke event, it breathes, absorbs the compounds, attaches it to the sugar, then they are stuck in the grape berry without being able to tell if it’s there until fermented, he said.
“We’re dealing with any number of compounds. It’s not really well understood how they’re digested or how they’re released or how any of that matrix works,” Donahue said. “We may not see stuff immediately, we might see it after ferment, and we might not see it for a year or two in a bottle.”
There are a lot of compounds in grapes that you can’t smell until yeast breaks the bonds.
It is difficult to measure because vintners are dealing with a vast array of grapes, growing in different soils, farmed by different people, and the smoke comes at a different time.
The smoke event might be the 2020 vintage hallmark and can be marketed for smoky foods or as a memory of the year, he said.
The Walla Walla Valley is lucky compared to what many other West coast wine regions are facing from the smoke and or fire events, he said.
By Chloe LeValley of the Walla Walla Union-Bulletin.
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