Portugal’s cork won a rare Trump tariff exemption thanks to lobbying on both sides of the Atlantic

Stick a cork in it

Cork’s sustainable harvesting process and its biodegradability are two reasons that many US winemakers have returned to plugging bottles with it after experimenting with closures made of aluminum, plastic and glass. In 2010, 53% of premium US wines used cork stoppers; by 2022, that had risen to 64.5%, according to the Natural Cork Council.

Cork taint, which gives wine a funky taste and is caused by a fungus in natural corks, was a big problem in the 1990s, and it pushed many vintners into aluminum screw caps and other closures, said Andrew Waterhouse, a chemist and director of the Robert Mondavi Institute of Wine and Food Science at the University of California, Davis.

The cork industry has largely solved that problem, Waterhouse said. In the meantime, the wine industry came up with new technology, like screw caps that can mimic cork in the amount of oxygen that they let into a bottle over time.

Many wineries, including Trump Winery in Virginia, now use both screw caps and natural corks. Waterhouse said that screw caps generally make more sense for a wine like rosé, which isn’t intended to age, while cork is the standard for aging wines.

“If you say, ‘Has this wine aged properly?,’ what you mean is, ‘Was it in a glass bottle with a cork seal in a cool cellar?’ Under any other conditions, it didn’t age the same,” Waterhouse said. “We’re always trapped by history.”