Taming of the Screw: Wine with screwcaps versus cork

screwcap wine
Credit: Time, Inc.

In the deep recesses of cramped winemaker offices, a fierce fight has erupted between cork and screwcap. And you’d think the elder brother would be winning, but he’s not. A few years ago, winemakers became fed up with “tainted” corks. Up to 10 percent of these closures contain a compound called TCA that contaminates wine, imparting a musty, wet dog flavor and smell. (It’s called being “corked” and this problem birthed the artful server dance called “tasting a bottle” in restaurants). Since the monopolistic cork industry sat on their hands and didn’t attempt to fix the problem, winemakers sought out a solution. They found it in the humble twist-off.

But Portugal’s cork tree country hasn’t gone down for the count. They’ve launched a multi-million dollar “I Love Natural Cork” public relations campaign which stokes today’s hot issues: “Natural cork in your wine bottle does more than just preserve and improve the quality and character of your wine,” their website reads. “It preserves a centuries-long way of life in the rural communities of the Mediterranean cork oak forests, its incredible wildlife as well as the planet by absorbing CO2.” They even include a pledge sign-up, goading guilt-ridden consumers into avoiding screwcap and plastic cork wines because it’s the environmental thing to do. Now doesn’t that make you want to hug a cork tree grower? Methinks they fear the competition.

After eons of arrogance and with their bottom line bruised, cork industry dominance is nearing the finish line. New Zealand and Australia have gone cuckoo for metal and now almost 80 percent of their wines are under screwcap rather than cork. Even American wineries — daring in a culture hyper-obsessed with appearances — are embracing their use, mostly for their white wines. Worldwide, 15 percent of all bottles sport metal tops and that number grows yearly. No wonder the cork industry is freaking out.

There are, however, two sides to every solution. Regardless of the taint Russian roulette, bottles stoppered with corks do allow minute amounts of oxygen to enter and coax the liquid into flavors of caramel and dustiness, giving it that “aged” appeal. Oak tree plugs also have history on their side. Used since the ancient Egyptians and Romans, they reportedly replaced rags as the closure of choice. And cork removal is decidedly sexier than the metallic crack of a screwcap closure.

Wet dog smell, however, can kill the mood.

Despite years of passionate editorial copy and PR, many American consumers still equate screwcaps with Mad Dog 20/20. It’s been a grueling Ali-versus-Foreman bout, but it boils down to this simple, now proven fact: Screwcaps keep wine fresher than cork. Gwyneth Olsen, winemaker for New Zealand’s Villa Maria Estate, has been working with metal closures for the past five years. A vehement supporter, she likes the fact that “the wine we put in the bottle is what the consumer gets.”

Naysaying wine collectors, however, doubt the age-ability of wines under screwcap, saying red wines require oxygen to develop. Until recently, winemakers couldn’t discern if aging was possible, but I learned first hand what aged screwcap wines taste like during a seminar at Washington State’s Hogue Cellars (read about that trip). Sampling red wines dating back to 2003, they tasted like they were frozen in time – as vibrant as the day they were sealed. Same thing happened with the white wines but time has its way with everything. The Hogue Genesis 2004 Riesling revealed a hint of honeyed richness associated with age peeking out from the glass.

For the majority of wine drinkers, this debate might be, well, debatably relevant. But since winemakers craft wines to be drunk within two years after bottling, this might change the rules. Imagine not ever having to ask if a bottle you received five years ago would still be drinkable? With a screwcap, it’s conceivable the grog could still taste like the winemaker intended. And that’s a big win in the wine scheme of things.

Some great wines under screwcap:

Hogue Genesis 2007 Meritage
Villa Maria 2009 Sauvignon Blanc Cellar Selection



  1. To 100% Cork:
    Looking at the percentages obscures the individual reality. If we assume that cork taint is in “only” the 1.5 to 2 % range, that sounds great. But if I happen to be the one customer in 50 or even 100 who buys a $50 bottle to enjoy for a special occasion with my significant other, and it has cork taint, I have just thrown away $50, and would have been better off buying my SO some lotto tickets. It both literally and figuratively leaves a bad taste in my mouth, and would make me reluctant to try the same wine again on the chance I would lose more of my hard-earned cash. This is against the vintner’s best interests.

    I understand there is a certain cachet in opening a bottle with a corkscrew to which the snap of the metal cap cannot compare. And yet, I have occasional struggles with cork that frustrate me quite a bit; namely, splitting or breaking corks, pieces of cork left in the rim of the bottle or in the wine, and seepage on older bottles from my cellar.

    I believe we will see more and more bottles of wine go under screw cap or (my favorite) the glass Vino-lok for the following reasons. As China and India and other 2nd-world countries emerge to take a greater role in consumption of wine, cork will be unable to keep up with the demand. If memory serves there were shortages of cork in the late 1990’s due to droughts in Portugal. Wait until a billion Chinese people start wanting wine. When I was a child glass bottles of carbonated beverages had a cork liner inside the metal cap. This has been done away with and no one cares. As wineries move away from cork, new ways will develop to retain the romance of opening a bottle, such as aerating and decanting before drinking. Eventually those to whom cork is important will be supplanted by the youth of tomorrow who will have grown up familiar solely with screw tops and glass.

    I agree with you that synthetic corks are a poor substitute for real ones. They are difficult to remove and I think I have tasted them in wine before (notably South American white wines in the late 90’s and early 2000’s). Another argument against them is recyclability.

    However, both glass stoppers and screwcaps are completely recyclable and generally go into the same bin as the bottle. In addition, they are easy to remove and provide a secure way to reseal the bottle after it has been opened. The glass stoppers are even classy-looking, and I can envision wineries that want to set themselves apart spending a little extra on specialty colored-or-shaped stoppers to attract the consumer.

    I think time is on the side of the alternative closures.

  2. Taint is the most misunderstood and misreported issue in the wine world. Often based on anecdotes, the incidence of wine taint has been blamed almost exclusively on cork closures. But the hard evidence firmly demonstrates that cork taint is no longer a widespread problem.

    First, let’s define taint. The taint typically associated with wine corks is TCA (2,4,6-trichloroanisole). It is a harmless but ubiquitous environmental compound that gives wine a musty flavor at very low concentrations (parts per trillion).

    While TCA does come from cork, it also comes from sources such as contaminated winery or bottling equipment, airborne molds or chlorine-based compounds in wineries and cellars. A 2010 study scheduled for publication in the peer-reviewed American Journal of Agriculture and Food Chemistry, for example, looks at how wine barrels may introduce TCA.

    Wine can be spoiled for many reasons unrelated to cork or TCA. Oxidation, a common problem with plastic stoppers, can make wine smell like candy banana flavoring. Numerous bacteria and molds can also spoil wine by making it taste like everything from rancid butter to sauerkraut.

    But when wine fails to meet expectations, the cork gets blamed. Indeed, a recent study of 3,000 wine drinkers found that one in 20 complained that their wine was “corked” when in fact it had come from a bottle with a screw-cap.

    The habit of blaming cork may explain why estimates of TCA contamination based on anecdotal evidence range from 2 percent to 10 percent and above. But a large and growing amount of hard evidence concludes that the incidence of TCA has dropped precipitously in recent years and is commonly measured at less than 1 percent of wines sealed with real cork.

    In 1999, before the introduction of numerous improvements to cork processing, wine chemist John Casey estimated the likely incidence of TCA at below 2 percent of all wines made in Australia. Casey based his analysis of the results of 19 studies involving over 35,000 wine samples.

    In 2002, a survey of 5,735 bottled wines conducted by the UK Wine and Spirit Association verified that only 0.6 percent had TCA contamination.

    In a trial by Southcorp in Australia involving 150,000 corks over nine years, the overall incidence of different types of cork taint was just 1.84 percent. Of this, 1.5 percent was due to TCA.

    Christian Butzke, Ph.D., one of the leading wine experts in the U.S. and a vocal critic of cork taint, stated: “TCA is no longer a major problem for the U.S. wine industry.” His findings at the Indy Wine Competition found cork taint to occur at levels at or below 1%.

    In a test of 500 bottles of wine, some of which included older vintages that would presumably have a higher incidence of TCA contamination, the French Wine Society found that four bottles, or 0.8 percent, were affected by TCA. The Society declared TCA a “non-issue.”

    Internationally renowned wine critic Robert Parker conducted a grenache tasting in late 2009 for almost 600 guests at Spain’s WineFuture. Less than 1 percent of the wine was affected by TCA.

    TCA levels are now 81% lower compared to levels found in 2001, according to the testing of more than 10 million corks by the Cork Quality Council.

    The decrease in the incidence of TCA is largely due to improvements implemented by the cork industry. The industry has two complementary approaches used simultaneously for dealing with TCA. The first is to use quality control measures to prevent contaminated cork from being processed into closures. The second, which is the “curative approach,” is to assume that TCA will be present and then to remove it. The results of the above studies indicate that these efforts have been a resounding success.

  3. Interesting dialogue. I too am very anxious about opening my expensive bottles of old Bordeaux from my cellar. I recently experienced a corked bottle of a well known Pinot Noir from the Russian River – very disappointing, and very a expensive lesson. It’s more widespread than you think. The sooner wines are screw-capped or vino-locked with the glass stopper the better as far as I am concerned

  4. The question “Cork vs screw cap” should be broken out by “drinkable now” vs “ageable” wine.

    In August 2009 WineRelease.com surveyed its subscirbers (430 consumer and 135 trade responded) asking screw cap vs cork for ageable vs drink now wines. 76% of consumers and 86% of the trade prefer cork for ageable wines but for wines drank within the year, 64% of consumers and 52% of trade prefer screw cap.

    To see the full results, click the “other” on the menu then scroll down to “WineRelease Surveys”

  5. I agree with Neil, though I do wonder how screw cap wines will be received down the road. There will be interesting discussions indeed in a few years.

    At the same time, I would like to see the debate between cork and screw caps stay about the quality of the wine. The 100% cork campaign is about one thing: protecting market share for the cork industry. The other arguments…the sustainability, et al, is a complete ruse. I think the author was spot on when she (I’m assuming it is Taylor here, forgive me if I am wrong) pointed out that after decades of ignoring the problems of their product, the cork industry is now faced with competition that they do not like.

    For my part, I’ll buy wine based on what I like, and I really don’t care how they are sealed. At the same time, I do hope that wine enthusiasts can see through the phony claims of the 100% cork campaign. They are about one thing: protecting, not a way of life, or our planet, but an industry that is struggling to compete with other, smarter alternatives.

  6. The problem wineries face with the cork versus screwcap decision for ageable wines is consumer perception. Neil, thanks for sharing that survey link. I’d love to know which trade folks answered the survey… supplier or distributor? There’s a wide range of opinion on this topic. In my experience, I’d guess around 4-6% of the wines I taste have cork taint, probably since I’m very sensitive to that flavor. It’s pretty frequent that I go to a trade tasting with about 100 wines and find at least one bottle that’s bad. Happened last week (Australian wine) and the pourer was pretty embarrassed she hadn’t tasted the juice first. Doh!

    I applaud aschaef’s response that 1.5% is still too much… there aren’t many other industries on this planet that would survive with that kind of failure rate. So why would a winery — when more and more studies are finding that screwcaps still allow wine to develop like cork does (albeit much slower) — choose a closure method that continues to have a failure rate? Doesn’t make much sense to me. Times are changing, thankfully.

  7. Taylor,

    The trade respondents are winery personnel.


Leave a Comment

Your email address will not be published. Required fields are marked *