Wednesday, October 15, 2008

Of Corks and Screwcaps

If you’re a wine lover, surely you’ve heard of the great cork controversy. Corks are routinely sanitized with chlorine. Chlorine can react with mold on corks to form a compound called 2,4,6-trichloroanisole (TCA), which can spoil a wine. In the best case, TCA merely robs a wine of all its fruit. In the worst case, the whole wine smells of musty paper, just like those old newspapers in your attic, and tastes just as bad. Other chloroanisoles and a bromoanisole are formed in the same way and are also responsible for tainting wine.

Receptivity to these anisoles varies greatly among individuals. I have a friend in the business who once opened a bad bottle and I told him it was corked from across the room. Even with his nose buried in the glass, he had a hard time smelling the cork taint. And I know another guy in the business who claims wines are corked that I can’t detect.

In any case, wines are being spoiled by these chemicals and the largest vector for contamination is corks. Various factions claim that this spoilage is acceptable or wholly unacceptable depending on their points of view. However, the issue has spurred the industry to look at alternative closures.

For several years, many wineries used synthetic corks, which fell out of favor. From our perspective at the restaurant, they were impossible to remove when first inserted into the bottles and then after a few months, they became so loose that they pushed right into the bottles at the mere touch of the corkscrew. Once these plastic plugs loosen, wines oxidize very quickly.

And, many other alternative closures have been proposed, tested, and found similarly wanting. The most promising “new” closure is one we have had for decades, namely the screw cap. Naturally, the screw cap suffers the stigma of having been the closure of choice for a lot of really poor jug wine for decades. Beyond the stigma, there is sentimental attachment to corks, comfort in the time-honored ritual of opening the bottle, and that wonderful aural stimulus—the unmistakable pop that we wine lovers adore—that anticipates the first sip.

All my traditional likes for corks are immediately overwhelmed when that first whiff or sip of a newly uncorked bottle is ruined by cork taint. This, more than anything, has convinced me that it is time for us all to move on and get used to screw caps for wines that do not need to be aged. The jury is still out on how wines age long-term under screw cap versus under cork. I worry that the wines will not age as gracefully under screw cap, but the evidence is not there to support my worry.

Still, from my perspective as a restaurateur, we don’t buy wines to age—very few of us can afford to tie up that much working capital—we buy wines to drink now. And I think most consumers do as well. In our business, initially the servers bemoaned the loss of the cork because it removed a lot of the tableside theatrics and romance. And, secretly, I am sure they were concerned for their tips: screwtops have not affected their tips in the least. Moreover, for by-the-glass pours, there is nothing easier for us than a screw cap. Unscrew, pour, rescrew, back in the fridge. And for customers who want to take a partial bottle home, the screw cap won’t leak all wine all over the car on the trip home. And the bottle will fit better in the refrigerator door without the cork poking out of the top.

Any trip to the grocery store or wine shop will show that the screw cap is inevitable. Already most New Zealand wines are under screw cap as are many lower end table wines. Australia and South America will soon have the majority of their wines under screwcap. On the one hand, I applaud this move. And on the other, I sure am going to miss that “pop!”


  1. Ed, I don't have any of those problems being I drink Miller Lite. They have these neat aluminum tabs that make it so easy to open and enjoy. Maybe I will start drinking a little more vino. It is way better for me I am sure.

    I'd kill for some of your crab cakes. Haven't had any really good ones since I was last in Annapolis, about 18-19 yrs ago.

  2. I don't know what to say about Miller Lite. I think you just admitted publicly to drinking it, too. My mother always told me not to say anything if I could not say something nice. Wait, I got it! Miller Lite makes a fine beer batter! It has no flavor to mess up the batter and it's cheaper than club soda!

    As for crab cakes, hie thee north and I will feed you all you can eat. Susan and Marshall are coming to lunch on Tuesday; surely you can join the party.

  3. Come on Ed, being a newcomer to the restaurant business and with no formal training as a chef is no excuse for hammering natural cork stoppers.

    The industry hasn’t used chlorine to sanitize corks for well over a decade. You are correct that chlorine can react with mold on corks to form TCA. Your statement that corks are the largest vector for contamination is no longer valid. TCA can also occur as “environmental” TCA in oak barrels and wineries themselves. New sanitizing protocols and the use of mass spectrometer instrumentation to detect problems are helping reduce and eliminate winery issues. That said: the cork industry has invested millions of dollars over the past decade to eliminate TCA from all known sources. The US-based Cork Quality Council, for example, tested over 2.5 million corks during a four-year period. The results show an 80 percent reduction of TCA levels in bulk cork imports since 2001. Dr. Pascal Chatonnet, a leading scientist and Bordeaux winemaker, stated at a recent wine industry symposium that his testing has shown a steady decline in cork related taint from 4.9 per cent in 2003 to a mere 0.2 percent in 2006.

    Regarding synthetic, petroleum-based closures: we are in agreement. In addition to being a poor substitute for natural cork, they just don’t work.

    Screwcaps are another matter. We agree that they are easy to open and offer convenience despite their “stigma” as a low quality jug wine closure. Where we don’t agree is that it is time to “get used to screwcaps” and embrace them as the alternative closure of choice.

    A compelling and often missing argument in the closure debate is the fact, and it is a fact, that alternative closures like plastic and aluminum take huge amounts of energy to produce and are not sustainable in any degree whatsoever. Natural cork, on the other hand, is the perfect green product: it’s sustainable, biodegradable, recyclable and totally renewable. No open pit mines or pipelines are required.

    A very positive aspect of the green movement is the fact that as consumers we can influence the world around us by our buying decisions. The next time you go to the grocery store or wine shop, think of the “upstream” implications of your choices. By choosing an alternative closure, you not only increase greenhouse gas emissions, but you devalue the very cork forests that support a rich, diverse, ecosystem, with employment opportunities for tens of thousands of people. Is a screwcap really worth the price?

  4. What does my being in the restaurant business for six years have to do with your argument? Obviously I touched a nerve.

    Your claim that I am “hammering” corks misses the mark. Really, I am chiding my customers who still have hangups about screwcaps. Screwcaps on fine wines are here to stay and to think otherwise is foolish.

    I believe that screw caps are a positive development and a technically superior closure for wines that need no age. But the closure is immaterial as long as we don’t have to deal with corked wines. Anything that reduces the amount of corked wines is a good thing. That competition from alternative closures has forced the cork industry to develop and sell a superior product is undisputable and welcome to us wine drinkers.

    Since you opened Pandora’s box, let me remind my readers that the cork industry is no saint from an environmental perspective. The abuses of the oak forests committed in the name of cork closures are well documented. Cork industry giant Amorim (do you work for them?) has spent a lot of PR effort in distancing themselves from this and trying to reframe the argument such that alternative closures appear a less green option than cork.

    This argument has some merit and I should have mentioned it in my original post, but it certainly does not factor in the shipping costs of cork versus alternative closures. One of the motivating factors for the Kiwis switching to screwcaps has been the cost of shipping corks around the globe to them from Europe. Consider the environmental impacts of this shipping.

    At the end of the day, while you state that your argument is compelling, I don’t believe that any of us can quantify just how green any given solution is. I certainly want to believe that a renewable resource such as cork is more environmentally friendly, but I don’t think it can be proven or at least easily proven. The environmental argument for corks, as for many other things, is mostly marketing hyperbole with little or no scientific basis.

    Finally, I’d like to remind readers that Pascal Chatonnet was not taking sides in the debate; he was merely reporting facts. He also said at the very same symposium that it is up to consumers to decide which closure is best. Consumers, it’s up to us.