Wines such as Pinotage, Carménère, Syrah and Zinfandel are popular for their ‘smoky’ taste, but nobody wants to drink wine affected by smoke taint.
Smoke taint occurs when grapes are subjected to wildfire smoke. The grapes metabolize aromatic compounds called volatile phenols, which can give the wine its unpleasant flavour.
Grapes on the vine show no sign they’re tainted until the fermentation process takes place – that’s when yeast breaks down enzymes, releasing the volatile phenols into the wine.
The only way winegrowers can tell whether wine is tainted is to taste it — the acrid, ashen, metallic taste of smoke taint is a dead giveaway a wine has been ruined.
Because there’s no way to tell if a grape has been tainted until the wine is made, smoke taint can cost winegrowers a lot of money because they typically have to destroy the wine.
Wesley Zandberg, a biochemistry and molecular biology assistant professor at the University of British Columbia’s Okanagan campus, has been studying smoke taint for more than five years and says there’s no clear consensus on what causes it and no proven method to protect grapes from it.
“There are a few things that make this so tricky and such a concern for the industry and that is our ability to perceive something by smell and taste involves an awful lot of synergy and chemistry. It is very true that even a tiny amount of these compounds related to smoke odour may taint a wine, but it is also true that very high amounts of the same compounds may be found in a very pleasant wine. There’s a lot of other things that react with these taints and influence our ability to perceive them,” Zandberg said.
Zandberg and his team thought they had found a solution by applying approved agricultural sprays to the grapes’ surface. But after testing it in the field, applying the sprays actually made grapes more susceptible.
Zandberg is working to develop ‘the ultimate test’ to determine whether grapes have been impacted by smoke taint. If Zandberg is successful, it could be a huge boon for the wine industry.
California’s devastating 2020 wildfire season cost its wine industry an estimated $601 million.
The Australian Wine Research Institute estimates that 2009’s Black Saturday fires in Victoria, Australia resulted in $299 million in lost wine revenues.
B.C. winegrowers also battle with smoke taint but it was a travel warning to the Okanagan that recently has hurt the industry. First the COVID outbreak, then a series of wildfires, each forcing cancellations to the region’s wineries.
“We were seeing reservations really firm up for this year, but with the smoke we’re seeing cancellations, said Miles Prodan, CEO of Wine Growers British Columbia. “People are not coming and that’s a problem because it could be smoky in Kelowna and nice down in Penticton”
As of Aug. 27, 236 wildfires were burning across B.C., 77 of which are in the Kamloops Fire Centre, which contains much of the Okanagan’s wine country.
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