The devastating fires throughout Northern California’s wine country over the last week hit so many areas of the multi-county region in so many ways that it’s hard to calculate or quantify the magnitude of the losses.
But one thing that was on the mind of winemakers and almost everyone connected to the wine industry was the potential damage from smoke in the wines.
Occurring in the midst of the harvest, the fires that ravaged wineries and vineyards in Napa, Sonoma, Mendocino, and Lake counties created numerous situations that could be expensive problems.
One is that much of the cabernet sauvignon in the North Coast was still on the vines as fires raged, spewing smoke in every direction. Potential smoke taint in wines made from those grapes could make wines that consumers won’t like.
This has occurred several times in the last few years, most notably in 2008 in Mendocino and northern Sonoma counties, where fires left some red wine grapes (which typically are picked later than whites) with a burned aroma that had a detrimental effect on how the wines tasted. And that hurt sales.
One descriptor for some of the 2008 reds came from a winemaker who said tasting smoke-affected reds was like licking an ashtray.
Following that harvest, many winemaking tactics were utilized to try to remove smoke taint from wines made from fire-affected grapes. Various forms of filtration seemed to have promise, but many of the wines still ended up smelling a bit odd.
“Right after filtration, the smoke seemed to be gone, but six months after bottling, the smoke came back,” said one winemaker.
A large amount of 2008 red wines couldn’t be sold under primary brand names. Much of it was sold off in bulk. Other batches were carefully blended with non-smoky wines and ended up in bottles with private labels, which sold at lower prices.
A few wineries even admitted they had a smoked aroma problem. They created “second label” wines and reduced prices for these wines significantly.
One of the problems in dealing with smoke taint is that it can come in various chemical forms, according to Santa Rosa winemaker and wine chemistry instructor Clark Smith. Some forms of smoke taint are radically different from others, he said, so one single treatment may not work for all the smoked wines.
The Australian Wine Research Institute has done most of the world’s important research in this area of smoke taint, and some of its scientific findings have been published in technical papers – but most such research has never been seen in the United States.
“The Australians have had several horrific vineyard fires in the last few years,” said Glenn McGourty, UC Cooperative Extension Viticuluralist for Lake and Mendocino counties. “That sparked most of their research.
“Most of what’s left out there (yet to be picked) is cabernet, and that’s a grape that most winemakers I’ve talked to don’t think will have smoke problems,” he added, speaking of California’s fire-hit regions.
A few smoke-tainted wines may be treated with reverse osmosis systems, winemakers say. But other issues also face many wineries as a result of the fires.
One of the most labor-intensive and costly could well be ash and soot clean-up and other sanitation issues. Winery sanitation is crucial to making wine that is not only sound and free of technical problems but is stable and conforms to prior vintages. And sanitation following firestorms calls for literally hundreds of hours of diligent cleanup.