I don’t want to give away too many personal details, but for reasons both obvious and obscure, I spent a good part of my weekend making the rounds at wineries. For the record, the obvious reason is “duh, wine.” I don’t mind sharing that one. Anyway, on one tour, the guide noted that corks made from real cork bark may be falling out of favor with wine-makers. I decided to explore the science of why.
For the past four hundred years, natural cork has been the plug of choice for wine-makers the world over. Cork is a particularly well-suited wood: the very best stuff comes from the Mediterranean region, and its structure is such that it can squeeze down into the neck of the bottle and expand or compress to match the shape of neck. This supposedly gives the wine a great seal, allowing it to mature without the threat of oxygen coming in and screwing things up.
But now, wine-experts are not so sure. The corks may not be completely effective in keeping air out. For a wine that gets drunk fairly quickly, that’s not such a big deal. However, for serious wine-drinkers who plan to keep and age their bottles, this air transfer means serious bad news: with too much oxygen, the wine can lose quality.
Unfortunately, that’s not the worst of the problems corks can cause. Have you ever popped open a bottle only to be greeted not with the heady, rich aroma of wine but with the stench of cork? That’s a wine that’s experienced some cork taint, which is just as unpleasant as it sounds. The estimates of the percentage of bottles on store shelves afflicted with taint go anywhere from 0.1% all the way up to 10-15%. That’s not great for wine producers, wine drinkers, or anyone really.
Cork taint comes from a compound called “2,4,6-tricholoroanisole”, or TCA to its friends. Now, these problems only occur under some circumstances, and do not mean that corks should be banned immediately or treated with suspicion. At this moment (OK, if you’re reading at a weird time, maybe not at this moment), cork companies are working to address the issue, but, so are producers of fake cork and cork-alternatives, like screw tops.
Screw tops may be where the industry is headed. They’re cheap to make, easy to use, and for a while, work much better than traditional corks at keeping air out. There is also absolutely no risk of TCA. However, screw tops have an image problem to overcome – many people associate screw tops with cheap wine, not the good stuff, and that can be a huge deterrent to purchase. This is a problem that can only be solved with marketing, so here’s to hoping the ad execs brew something good.
What it all boils down to is that wine makers are going to have to think about and adjust the stoppers that they use for their wine. Instead of treating every wine the same way when it comes to plugging the neck, it’s time to look at the different needs of different wines, acknowledge the limitations of our technology, and adjust the industry accordingly.
And now – pour yourself a glass!