Until recently, though a cork was no guarantee of a quality wine, a bottle closed by a screwcap indicated to even the most casual observer that the wine was, well, something less than exceptional. Screwcaps were associated with cheap booze drunk from brown paper bags, not pricey bottles of Cabernet or Fume Blanc.

In spite of the screwcap’s somewhat tarnished reputation, a number of producers of mid- to high-priced wines have taken the mold-breaking move of switching from corks to screwcaps. Natural cork costs are rising and an unwelcome oxidation from natural cork shrinkage is always a possibility for long-held wines. But it was cork taint, or TCA (a compound called 2,4,6-trichloro anisole) that finally put a cork in it.

TCA has led to more winemaker ulcers and sleepless nights than glassy-winged sharpshooters, late-season rains, and the grape glut put together. Winemakers can spend years creating the perfect wine — managing the vineyards carefully, monitoring the harvest on an hour-by-hour basis, crushing carefully, blending with panache, only to find the very last thing that goes into a bottle — the cork — is infected with TCA, causing a "corked" wine. TCA infects an average of 6 percent of all bottles of wine, and is remarkably potent; TCA can be detected at 6 parts per trillion. In fact, a tablespoon of TCA would be enough to make the entire U.S. production of wine this year "flawed."

RECOGNIZING CORK TAINT
TCA creates no health hazards, but it does cause a subtle but unpleasant taste in the wine. "TCA causes a musty, foul aroma that resembles the smell of old dirty gym socks, or mold in your carpet," describes Ralph Swagler, a Sonoma County wine educator and wine judge.

Palates differ. Even the most experienced wine judges might detect TCA at different concentrations. But even more troublesome for winemakers is that the majority of wine consumers don’t recognize the taste of TCA as cork taint.

"Most wine drinkers haven’t been educated on what TCA tastes like," says Tim Meinken, owner of Sapphire Hills Vineyards in the Russian River Valley of California. "So when they get a corked bottle, they say, ‘Oh, this wine is interesting.’ And they never order it again." Sonoma County winemaker Carol Shelton, of Carol Shelton Wines, worries that a wine drinker’s inability to recognize cork taint hurts winemakers. "We know that about 6 percent of our bottles must be corked. But we don’t get 6 percent returned. We don’t even get back 2 percent. I’d rather get a bottle returned than have the customer say to their friends, ‘I don’t much care for it.’ I suspect a lot of people decide they don’t like our wine, when really, they don’t like the taste of cork taint."

On the California central coast, John Clark, a Corbett Canyon winemaker and one of the earliest American adopters of the non-cork Stelvin closures, agrees. "I don’t think most wine drinkers recognize the taste of TCA. This is our worst nightmare. The thought of wine drinkers going away thinking they didn’t like the wine, when in fact the problem is cork taint, is unforgivable. We’ve watched with interest as more high-end wineries move to bottling a percentage of their wines with screwtops. But it shouldn’t just be the appreciators of $150 bottles of wine that enjoy the taint-free guarantee that the Stelvin closures offer. In fact, it’s even more important that the casual drinkers have a good experience."

When it comes to white wines or wines with low aging requirements, experts agree. Screwcaps — or even boxed wines in airtight plastic bags — simply provide a more reliable seal. But switching to screwcaps is not an easy move, says Michael Brajkovich, winemaker for Kumeu River Wines in New Zealand. "It must be recognized that the change to screwcap usage away from the more traditional closures is a controversial one. The wine industry is inherently conservative and traditional, and change does not come easily." The real question plaguing winemakers is: Will consumers accept unconventional closures? Swagler says eventually they’ll have to.

THE TAMING OF THE SCREW
Early pioneers in marketing screwcapped (or even boxed) wines say presentation is everything. The Sonoma Hills boxed wine is modeled after the Godiva chocolate box, and most upper-end wineries experimenting with screwcaps wrap the screwcaps in foil. The French-manufactured Stelvin closures (the most popular non-cork stoppers) are designed with a long skirt that hides the screwcap itself.

"The problem is not one of performance — many wine companies internationally kept their ‘library stock’ of wine under screwcap going back over 20 years. The problem is one of public perception," says Dave Williams of New Zealand’s Jackson Estate wines. "The closure had been associated with wine of inferior quality, and was therefore perceived to be ‘cheap.’"

In 1999, PlumpJack Winery in Napa Valley (founded by San Francisco mayor Gavin Newsom) released one of the first luxury wines bottled with a screwcap. If you could find that ’97 vintage Cabernet in the marketplace, PlumpJack winemaker Anthony Biagi says, it would cost you about $200. Luckily, PlumpJack was in a position to take the risk. There was little chance of retailers putting PlumpJack’s $135 bottles in the bargain bin. "We had two vintages under our belts that were critically acclaimed by Robert Parker in Wine Spectator," Biagi says. "We had the reputation for making tremendous wine."

A number of studies are under way to determine the long-term effects of screwcap closures, but most early results are promising. After conducting a four-year study on the effect of five different closures (including natural corks, synthetic corks, and Stelvin closures) on its wines, Washington state’s Hogue Cellars began bottling 70 percent of its wines with Stelvin caps. A panel of Hogue winemakers and wine trade professionals tasted a 1999 Hogue Genesis Merlot and a Hogue Fruit Forward Chardonnay at six-month intervals. "We came to the conclusion that Stelvin screwcaps best preserve the quality of wine in the bottle," says David Forsyth, director of winemaking at Hogue Cellars. "For us, it’s all about delivering high-quality wines, and screwcaps more effectively preserve the purity of the fruit and winemaking flavors."

Australian and New Zealand winemakers have led the charge toward screwcap closures, but American and even traditional French winemakers such as Jean-Claude Boisset, Domaine Laroche, Georges Duboeuf, and Château Margaux are experimenting with screwcap bottling. Alsace producer Jean-Pierre Frick of Pfaffenheim has announced a move to the crown caps seen on beer or soft drink bottles, opting for crown caps, he says, because screwcaps still have a very negative image in France.

THE LOSS OF THE ‘POP’
Experts say it’s only a matter of time before consumers accept that screwcaps produce a more consistent wine. But what will it take before wine drinkers are willing to give up the romance of the cork? No matter how deluxe the screwcap, the theater of bringing a bottle to the table and the satisfying sound of a popping cork is inevitably lost. Nonetheless, Brajkovich insists, "The romance of the cork must give way to the true romance of great wine, time after time, with no disappointments due to tainted or oxidized wines."

While many winemakers agree that screwcaps are superior for wines with low aging requirements, the jury is still out for red wines that were meant to have long aging periods. Early trials show that screwcaps can slow the aging process, creating what some call "Peter Pan Wines" — wines that remain too fresh and take too long to develop their full maturity.

Long-term scientific evidence is sketchy at best, so the debate rages. Some believe that a cork helps the wine to breathe, and therefore ages wines more gracefully. Others say that good corks don’t breathe, it’s the air between the cork bottom and the wine that provides the oxygen wines need to age. "It is not necessary — in fact it is highly undesirable — that a wine should ‘breathe,’" Williams says. "This misconception is often repeated, but it is quite incorrect. If a wine ‘breathes,’ then oxidation will occur and the wine will spoil. Wine ages anaerobically — that is, with the oxygen sealed in the bottle. To age gracefully, a wine needs a very good seal. A cork can provide this, but there are inconsistencies. A screwcap will always provide a good seal."

MAKING THE SWITCH?
Winemakers, including the members of the slightly irreverent but sincere "New Zealand Screwcap Wine Seal Initiative" (whose motto is: "We’ve screwed ’em!"), enthusiastically evangelize the benefits of screwcaps, but few winemakers are ready to commit to long-term aging in screwcaps. Still, nearly 98 percent of all wines are consumed soon after purchase and many wine producers are creating higher pH and lower acidity reds that are meant to be drunk young, so these concerns might only affect a small percentage of wines being produced today. Evaluating bottlings of the 1995 Penfolds Bin 389 and Bin 2 wines, Penfolds chief winemaker Peter Gago said: "The wines were bottled at the same time, one in a Stelvin closure, one under a cork. There is a subtle difference between the two wines, but no more than you would expect from a wine stored in a cold cellar versus a wine stored in a really cold cellar." But Gago isn’t ready to make a wholesale switch to screwcaps just yet. "The earliest vintages of the Grange, such as 1953, are still drinking beautifully under cork. No one knows what 50 years under a screwcap will mean to a great red like that. We have a responsibility toward the people who invest in our wine to be somewhat conservative."

Wine lovers may someday soon look back at natural cork as an archaic and somewhat primitive bottle closure. "Popping a cork with a flourish is fun," Swagler admits. "But for a wine lover, it’s the taste that really matters. There’s nothing more disappointing than looking forward to a particular bottle of wine, only to find it is corked. Once that has happened to you a few times — or a few dozen times — screwcaps start to seem like a really good idea."

Lisa Anderson Mann is a writer who considers herself lucky to live in the heart of California‘s wine country.