Smoky tastes in South African red wines have long been remarked on by reviewers. They’ve been put down to the effect of local soils or winemaking practises. But the actual reason appears to be much simpler and, with hindsight, obvious.

Research from Australia, after devastating forest fires one year in their wine lands produced flavours in wine described as smoky, burnt and ashtray, indicates that wood smoke is the culprit.

Bush fires are an annual feature in South Africa’s wine lands. I have been a visitor almost every harvest since 1996 and regularly see fires, closed roads and subsequent blackened and scorched land.

The 2016 vintage, which takes place in the Southern Hemisphere in the first few months of the year, has been taking place among serious fires. One such blaze raged for five days across the Simonsberg mountain in the middle of the prime Stellenbosch wine region. Some of the regions most famous vineyards grow on its slopes.

I visited Delheim Winery, one of the founders of the Stellenbosch wine route, to see orange and brown leafed forests scorched by fire and still smoking blackened fields. Delheim’s Raymond Noppé blogged ‘We were fortunate that we had minimal damage to our vineyards but some Sauvignon Blanc, Chardonnay and Gewürztraminer blocks suffered partial scorching of vines and bunches’.

But it’s the black smoke which eventually comes to ground that is blamed for smoke taint in wine. Its effects are noted most in red wine because smoke particles settle on grapes. While white grapes are pressed and only their juice is fermented, black grapes are fermented together with their skins in order to extract colour to make red wine.

The Australian Wine Research Institute (AWRI) has recommended actions for winemakers to take to reduce and hopefully avoid the effects of smoke damage. They point out that as well as settling on grapes the ‘volatile aroma compounds enter the grapes directly through the skin and also, to a lesser degree, via the leaves.’

This growing season in South Africa has seen record high temperatures, coupled with minimal rain fall and drought, resulting in bush fires that have been more prevalent and fiercer than usual.

But harvest time fires are a fact of life. However armed with AWRI’s research this year’s wines and future vintages shouldn’t have those smoky tastes.

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Peter F May is the author of Marilyn Merlot and the Naked Grape: Odd Wines from Around the World which features more than 100 wine labels and the stories behind them, and PINOTAGE: Behind the Legends of South Africa’s Own Wine which tells the story behind the Pinotage wine and grape.

Disclosure: Peter May paid for all travel to and in South AFrica, tastinga, meals and wines.