If you’ve shopped for wine lately, you may have noticed that bottles you’d actually consider buying are sporting a screw cap rather than a cork. What’s going on here? The screw cap is getting respectable. For centuries, cork has been the stopper of choice for sealing wine, but it’s far from perfect, which is why screw-cap wine bottles could be more than a passing thing.
True cork has history
Cork comes from the bark of a particular species of oak, with most cork-producing trees in Portugal, Spain, and Algeria. After the actual corks are cut, they’re rinsed, most often in hydrogen peroxide or chlorine. While this bleaches the cork to a uniform color and rids it of mold, it can also create problems.
When a wine is “corked,” residual bleach is the culprit. A compound called trichloranisole (TCA), which taints the finished wine, can result. If you’ve ever smelled a musty, wet-cardboard odor when tasting wine, you know what I mean. (If you haven’t, chances are you will: it’s estimated that 2 to 10 percent of all cork-finished wines are affected by TCA.)
Synthetic corks solve one problem but may cause others
A growing number of wineries are using alternatives to natural cork.
Synthetic corks made of polymer were originally thought to be the answer to TCA spoilage. But they’re turning out to cause problems, too. Peter Bell, winemaker at Fox Run Vineyards in New York’s Finger Lakes region, says that synthetic corks seem to admit more oxygen than a natural cork. “Wines that I know to be delicious with beautiful aromas seem to lose those qualities more quickly under synthetic cork,” he says. Bell has found that Riesling and Pinot Noir seem to be more vulnerable than Cabernet Sauvignon or Chardonnay.
Composite corks are made from natural cork particles held together by a binder. While some are easy to remove and leave no trace elements in the wine, the worm on the corkscrew can cause the cork to crumble, leaving particles in the wine. And the binder, say many winemakers, imparts an odor to the wine.
Screw caps are gaining ground
Despite its association with bad wine, the screw cap (also known by the trademark name, Stelvin) is probably the most effective way to seal a bottle of wine, as it’s airtight and leaves little chance for contamination.
Wineries especially keen on screw caps use them for premium wines. Winemakers in New Zealand and Australia are particularly enthusiastic. In the United States, wineries in both Oregon and California are starting to embrace screw caps, in particular, California’s Bonny Doon Vineyard winemaker Randall Grahm, who admits that he’s “privileged to have customers who are open-minded to experimentation and innovation.”
“A lot lies in the package design,” says Michael Skurnik, a wine importer who carries premium screw-cap wines. “The bottles needn’t look down-market.” (Some wine lists denote screw-cap bottles as “cork free.”)
But can wine breathe without a cork?
Some worry that a screw cap, which is airtight, will arrest aging, arguing that cork, porous and flexible, can let minute amounts of oxygen into the bottle. Ed Sbragia, chief winemaker of Beringer vineyards in the Napa Valley, says he’s reluctant to change until there’s something that works as well as a cork. “I think of wine as a living, breathing thing, and I believe it benefits when a goodquality cork is used.” But Vernon Singleton, professor emeritus of enology at the University of California at Davis, says that a properly corked bottle admits little if any oxygen. The good effects of bottle aging, he contends, depend on slow-term changes that happen without oxygen. For now, the debate goes on.
In my opinion, screw caps are appropriate for less expensive wines meant to be drunk within a year or so. But, as both a sommelier and a wine drinker, I’m reluctant to give up the uncorking and decanting rituals that go along with an aged bottle of fine wine. So, despite the problems inherent in cork, I think it will be a while before we say goodbye to this time-honored method of stoppering a wine bottle.
Screw cap wines you’ll want to drink
• Rosemount Estate Diamond Riesling
• Wynns Coonawarra Estate Riesling
• Jacob’s Creek Reserve Riesling
• Annie’s Lane Riesling
• Wolf Blass Gold Label Riesling
• Penfolds Eden Valley Riesling
• Mount Horrocks Riesling
• Grosset Polish Hill Riesling
• Bonny Doon Ca’ del Solo Big House White
• Bonny Doon Ca’ del Solo Big House Red
• Bonny Doon Clos de Gilroy
• Bonny Doon Old Telegram
• Sonoma-Cutrer Founder’s Reserve
• PlumpJack Cabernet Sauvignon Reserve
• Paul Blanck Alsace Pinot Blanc
• Villa Maria Private Bin Sauvignon Blanc
• Lawson’s Dry Hills Sauvignon Blanc
• Jackson Estate Sauvignon Blanc
• Kim Crawford Sauvignon Blanc
• Kim Crawford Chardonnay
• Wairau River Sauvignon Blanc
• Kumeu River Chardonnay
• Felton Road Pinot Noir
• Villa Maria Reserve Pinot Noir
• Willakenzie Estate Pinot Blanc
• 2001 Willakenzie Estate Pinot Noir
• 2001 Argyle Merlot
• 2001 Argyle Syrah