In a recent article in the New York Times , South African wine and the “burnt rubber” issue came up again.
South Africa is the world’s ninth largest producer of wine, an up-and-comer in the global marketplace, the winner of more than its share of accolades in international competitions. How, then, have some of its wines been linked to a stench commonly coughed up by a junkyard fire: the bouquet of burnt rubber?
Most of the answer lies within the lively prose of a British wine critic, Jane MacQuitty of The Times of London. In late 2007, she tasted a run of South Africa’s flagship reds and wrote that half were tainted by a “peculiar, savage, burnt rubber” odor. In a later column she called a selection of the country’s best-rated reds “a cruddy, stomach-heaving and palate-crippling disappointment.”
Here in the glorious wine lands of the Western Cape, where the grape vines grow against a backdrop of stunning mountains, her comments were infuriating and perplexing and even derided as loony. No particular reds had been singled out by Ms. MacQuitty. Exactly which wines carried the scent of smoking steel-belted radials?
Wine aficionados began taking sides: yes, there is definitely a telltale rubbery odor, and no, it is all in your imagination. South Africans who dismissed the criticism were demeaned as burnt rubber denialists. Worse, they were accused of “cellar palate,” being so accustomed to tainted wine that their taste buds now welcomed it.
Exporters were particularly troubled. About 28 percent of the 300 million liters of South African wine sent abroad in 2008 went to Britain (and 4 percent to the United States). Many consumers do not care where a bottle originates so long as it costs about the same as a six-pack of beer. Such indiscriminate drinkers are likely to switch brands rather than risk a mouthful of charred galoshes.
“We prefer that people use the term acrid rather than burnt rubber,” said André Morgenthal, the spokesman for Wines of South Africa, which represents the exporters. “But whatever you call it, it has not been scientifically proven that the flavor even exists. We have committed our best people to find out.”
Indeed, for the past year vine-and-wine detectives from the department of viticulture and oenology at Stellenbosch University have been working the case. The “burnt rubber team” includes sensory scientists and analytical chemists. They taste, they sniff, they scratch their heads.
They are looking for the golden thread that ties together a single taste that was born in multiple locations. Is the problem with the root stock, the soils, the storage, the bottling, the techniques of fermentation? Gas chromatography is being used to separate wines into their chemical compounds, searching for a culprit among the molecular units.
Professor Bauer said each person’s perception of taste is different. One man’s burnt rubber may be another’s sun-dried tomatoes. “People’s descriptions are imprecise,” he said. “If you don’t like a wine, you come up with your own set of terms: it’s too dry, it’s medicinal, it’s cat” urine.
The team’s first task was to find out what aroma was being likened to burnt rubber. A tasting of 60 wines was organized last year in London and included critics who had sided with Ms. MacQuitty. They fingered nine reds as burnt-rubber impaired.
These wines were returned to Stellenbosch, where the lineup of suspects was handed over to a second panel of tasters. They agreed that all nine had an “off” character but concluded that only two carried the pungency of what some might identify as rubber.
These two wines were considered a good start, however. Tasters could be trained to recognize that particular flavor, and as other wines were sampled under controlled circumstances, two became 10, and 10 became 20, enough wine with the same maligned taste to weed out some obvious possibilities.
No link was found to either the variety or the vintage of the reds. The stigmatized scent was found in wines from other countries too.
These conclusions square with the theories of some of this country’s leading winemakers. Pure and simple, they blame bad winemaking for the burnt rubber taste. Specifically, they cite the occasional inattention to certain sulfide compounds that can form during fermentation.
Read full article: New York Times