Bordeaux wine snobs have a point, as per this model

With machine learning, scientists are trying to chemically define the murky concept of terroir. The models might be useful for detecting wine fraud

- VIRGINIA HUGHES

IN THE BORDEAUX REGION of southwest France, scores of vineyard estates transform finicky grapes into bold blends of red wine.

Some bottles sell for thousands of dollars each. Prestigious chateaus boast about the soil, microclimate and traditional methods that make their own wine superior, an inscrutable mix known as terroir.

"It's one of those terms that the wine industry likes to keep a bit mysterious, part of the magic of wine," said Alex Pouget, a computational neuroscientist at the University of Geneva.

Dr Pouget is trying to apply chemical precision to this je ne sais quoi. In a study published Tuesday in the journal Communications Chemistry, he and his colleagues described a computer model that could pinpoint which Bordeaux estate produced a wine based only on its chemical makeup. The model also predicted the year in which the wine was made, known as its vintage, with about 50% accuracy.

Although wine connoisseurs often claim to be able to distinguish among wines from top estates, they rarely do blind taste tests, he said. "People have made those claims for decades, but we've never actually had an objective measurement that showed that this was true," he said.