Putting a Cork In It

by Francoise Villeneuve
September 2010

Your mind probably doesn’t automatically go to cork when you think table-thumping, red-faced, hoarse-voiced debate. But as George M. Taber, author of To Cork or Not to Cork: Tradition, Romance, Science, and the Battle for the Wine Bottle says, “in the wine industry, [it’s a] very hot emotional issue. [For] some people it’s like a discussion of religion. People are either pro-cork or not.” One of the big problems with having an opinion is that while you may be able to tell just by looking at a bottle whether it’s sealed with a screwcap, you can’t necessarily tell anything else about the closure—is it a natural cork, a plastic cork, a glass cork or something else? It could be any of a number of popular choices.

Wine industry folks have a handful of usual suspects to look to when it’s time to geek out about TCA-rates (trichloroanisole, a.k.a. cork taint), like cork, plastic, screwcaps, glass, and a couple of others still in development. This may end up actually being a plus for sommeliers; they have the ability to ask their distributors for certain types of closures to taste the wines on their own merit and help the customers who have preferences about what closure is used to make an informed choice with knowledge about each particular wine.

Cork It

Twenty five years ago natural cork was living the good life. Cork ruled the wine closure market with little to no resistance. A whopping 98 percent of bottles were sealed with cork. There wasn’t much that pushed cork to better itself. After all, there was no competition; not much incentive to trouble-shoot why “corked” bottles were happening, or whether they were meeting a particular standard, because they were the standard.

Cork had tradition on its side; it’s been used to seal containers since 500BC. In fact, right up until 500AD corks ruled the roost until the Swiss came up with an ingenious idea: wooden barrels. The barrels, with their hardy durability, basically took over from the cork-stopped clay amphoras.

And so it continued until about 1600. Everything was stored in these wooden barrels and consumed young to avoid deterioration, until England developed a sturdy glass bottle much thicker than the standard glass that could stand up to transport in wagons. Suddenly cork was necessary again and bottle closures very similar to modern-day corks were used right up until the 1970s and 80s. The bottle also meant that wine could now be stored for longer periods of time with controlled oxidation—in other words, aged.

That 1982 bottle of Bordeaux you’ve put by for a rainy day? If it were kept in wooden barrels, it would have begun deteriorating as soon as it made with contact with the air. In fact, before cork and glass bottles, by the time a new harvest came around, the harvest from the year before was worth virtually nothing.

But bottles had their problems too. A certain number of bottles from every harvest were always affected by cork taint; the wine had a musty aroma and flavor, a bit like a damp basement. The cause was a mystery. Once again the Swiss came to the rescue. They uncovered the real culprit in the 1980s—trichloroanisole, or TCA.

Eliminating it was another matter. This mission spawned decades of research and alternate closures. The more recent development was great growth in screwcaps and other alternate wine closures. “The growth of the plastic cork industry has been fairly level for the last few years,” says Taber. The percentage of corked bottles is hotly debated and constantly argued against. It’s either one in every case, one in every 100, or any number of other statistics, depending on who you believe.

A major plus for cork is that unlike all of the other closures it’s recyclable and renewable. Sure there may be areas in the US that recycle screwcaps, but most don’t. You may have seen the ad campaign on facebook, twitter, and in the media recently, funded by the Portuguese cork industry and their supporters; they don’t focus on the romance of cork, but on sustainability.

Patrick Spencer of the non-profit group Cork Reharvest focuses on the environment in his campaign to get restaurants to start collecting their corks for recycling. Cork oaks are harvested sustainably, and since their bark is only stripped every few years, the part of the tree used for cork production grows back. Since the forests, which are mostly in Portugal, are protected land at the moment, Spencer insists that the fall of cork “would be second most devastating loss after Amazonian rainforest.”

The loss of an entire industry is pretty daunting too. “Ninety four percent [of cork farms] are owned by individual family farmers who have been farming these forests for generations,” says Spencer, all of whom would lose their livelihood if cork experiences a sudden loss in popularity. Because cork is porous, it can be used in fashion, textiles, and home furnishings with great success. You know those ritzy soft tiles some homes have that supposedly offer great insulating properties against the clamor of little Billy’s clomping feet? Those can be made from recycled cork.

Restaurants can play a huge part in the push for a cork support—Batali & Bastianich Hospitality Group has committed to recycle their corks and many Whole Foods branches now collect corks for recycling. Spencer asks restaurants in areas without a collection center for recycling to hold off until they partner with local companies. “If we have restaurants packing up corks and sending them from Cape Cod to Salem, Oregon, even if we get a box of 30 corks, it becomes a negative as opposed to a positive, because it’s traveled across the US.”

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Everything goes plastic at some point. And corks are no different. Ten to fifteen years ago, plastic “corks” started seriously muscling in on what had been cork’s native territory. For one thing, they were cheaper, and were a viable solution at the time for the problem of cork taint. Unfortunately, they also posed the same environmental problems as other plastics. They’re made using petro-chemicals, so they aren’t commonly recycled and aren’t sustainably produced.

For the past decade plastic has remained the second most common closure for wine, despite the slight difficulty actually getting them to come out of the bottle. This is half of the problem. Though it’s true that they don’t really present issues in the cork taint department, they also don’t let any air enter the bottle for the slow oxidation that is crucial to the aging process.

But as long as you stick with young wines, that really isn’t an issue. Maybe this is why plastic corks aren’t making much headway in the elite world of high-end wine. Let’s face it, they’re not sexy, or as Taber puts it, “I can’t imagine a man proposing to his wife over a bottle with a plastic cork in it.” But, romance aside, they are still the most common choice for competitively priced bottles.

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Screw It

Screwcaps, which were developed as wine closures after plastic corks, came next, and have slowly worked up to a respectable 13 percent of the market. Their segue into America has been fairly slow, maybe because people associate them with harsh memories of cheap plonk. It’s true that screwcaps (or Stelvins) were a big hit in Australia and New Zealand for budget wines before they really caught on in the US, but many premium wineries in America and abroad have now adopted the screwcap for their younger wines to be consumed immediately—some of the last people you’d suspect.

California winery Bonny Doon talks about the easy acceptance of their screwcapped bottles. However, if you look at the explanatory blurb on their labels, they still feel the need to justify their unorthodox choice. Perhaps this is because they pose the same issue as plastic corks; they stubbornly block out all air. Mining aluminium is not a sustainable process either and the caps are not generally recycled by plants in the US, so they are not for the environmentally-conscious. They do have practicality on their side though. If you suffer from wine obsession and wanderlust, and take your bottle of wine on-the-go, what’s the first thing you forget? A corkscrew.

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The Glass is always Greener

Glass and other closures make up the rest of the market, but have yet to seriously threaten cork’s position as the top dog in the wine industry. The poshest of wine closures, the glass cork doesn’t come cheap. The Vino-Seal, a glass cork made by Alcoa, came onto the scene in the last 10 years in America, although it’s been around in Austrian and German wineries for some time now. Mainly it just looks nice—it screams elegance, and might make a good marketing tactic for reserve bottles—but because of the cost it has never really inspired much enthusiasm. A few wineries in California do use it, though.

Glass stoppers actually had a brief fling with wine in the 1600s, but they were too fragile and kept shattering or cracking in the bottle when it was opened. A big development here was a small ring of plastic that lifts the cork from the neck slightly, so it allows trace amounts of air to enter the bottle—something that neither plastic corks or screwcaps allow. It is easily resealed and, like screwcaps, there is no need for a corkscrew. The romance factor isn’t really compromised as it emits a satisfying “pop” when opened. So far no health concerns have come up, as only the glass touches the wine. What’s more, glass is readily recycled. In the end, Taber predicts it’ll come down to a fight between plastic corks, screwcaps, and natural cork.

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The Romance

Even after diligently weighing the pros and cons, the decision is largely emotional. Most of that is due to what Taber calls “romance,” in other words, the ritual of the opening of the bottle tableside and the presenting of the cork enhances the dining experience for special events, or as Anthony Bourdain would put it, "you're less likely to get laid after dinner if your wine is a screwtop." The long and the short of it is, if you like the wine, drink it and screw the consequences.

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