South Okanagan wineries keeping close eye on smoke taint in grapes as fermentation begins

As winemakers finish picking their grapes and head into fermentation in the South Okanagan, it is the first time they will be able to taste whether their grapes have been affected by smoke taint.

Smoke taint is the influence of smoky flavour that can occur when the particles from wildfire smoke land on grapes. When the grapes are ripening and develop a wax coating, the particles can permeate the grapes and bind with the sugars.

Given that two major wildfires threatened the South Okanagan this summer — Nk'Mip Creek and Thomas Creek — local winemakers have been understandably concerned.

Valeria Tait, winemaker and general manager at Gold Hill Winery, explained that when the particles bind with sugars in the grape, you can't tell if the smoke is in there through taste or smell.

Winemakers have no way of identifying it until the fermentation process begins, when it becomes aromatic once again.

“That's why it's a time-dependent thing and that's why it's really difficult to assess when you're harvesting,” she explained.

“We don't know until there's alcohol what the extent of it will be because it's an alcohol-soluble molecule.”

Smoke taint in a wine doesn’t always mean it’s ruined, since the level of taint can differ. At its worst, however, the wine is incredibly difficult to salvage.

“If you've ever picked up after your parents have had a party and snuck some beers and people have used one as an ashtray... It's exactly like that. It's like you just licked a wet ashtray that has alcohol in it. It's very unpleasant.”

If the levels of smoke influence are quite subtle, it’s easier to manage.

“It comes across as if you put the wine in an extra toasted barrel so it actually can be quite nice. And it can be something that you welcome as a flavour in a bold red wine. In a white wine, it's a disaster.

“But there's a lot of gradation of nuances of smoke influence. So it can be very light, to extreme.”

While Gold Hill Winery’s grapes are so far not showing signs of taint, Tait has heard from others in the region who are already dealing with it.

“I have fellow colleagues who have tasted smoke influence right at the press pad, like with whites when they were pressing off about a month ago and in some of their wines, but it's so hit-and-miss, it's completely random.”

The two major wildfires in the South Okanagan spread smoke and ash across the valley throughout the entire summer.

“We had some considerable wildfires in the summer but much earlier than we would normally have them. So winemakers are concerned because now we're in new territory since we have not experienced wildfires so early and the possibility of smoke influence so early," Tait said.

And the closest winery to the fire won’t always be the one that is inflicted with smoke taint.

“We had a fire that was very close to our winery in August, the fire that started near Osoyoos [Nk'Mip Creek]. And I was quite worried at the time, but our fruit was quite covered. So we had a lot of leaf cover and we didn't expose any of the clusters, we didn't do any leaf pulling,” Tait explained.

“I feel like we didn't really get a lot of particulate matter on the grapes. But you know, time will tell.”

And if grape growers are left with badly tainted grapes, there’s little they can do to recover. Production insurance can cover grapes for losses because of a smoke influence, but it isn’t straightforward.

“If you're a grower and a winery refuses the grapes because of smoke influence, you can get compensated for that loss of revenue.”

From a winery's point of view, it becomes more challenging to get insured for loss of wine production, because it's a product that's not an entity yet.

“So you can get covered from losses for grapes, but really, it's a new area and there isn't a really well developed or well thought out program for compensation.”

“Sometimes you don't know until four to five months after harvest that you have a problem. So how do you go back to the grower who's already been paid and you know, expect them to bear the cost of that influence?”

Winemakers continue to learn how to adapt to the changes with each growing season, whether it brings floods, drought, heat waves or heavy smoke.

“I feel like this is going to be an annual threat that we're going to be dealing with, something that's going to be an ongoing issue. With time we're getting more and more experienced with it, we're getting more knowledge about how to deal with it, what to do with the grapes when they come into the cellar.

“It's just one more challenge that is added to the terroir of growing grapes in our climate.”