Cork, Non-Cork, and Corked

Wine bottles have traditionally been sealed with cork, specifically from Quercus Suber L., the cork oak tree. And, the lovely nation of Portugal is home to more cork oak than anyplace else in the world. If you walk down the streets of any city, town, or village in Portugal, you're likely to find the streets lined with this amazing tree. But, this is not a blog about trees, it's about wine and related topics and today, we're going to discuss the pros and cons of sealing those bottles with cork. In order to discuss the pros and cons, though, we're going to need to compare with other methods of sealing, so we'll touch on synthetic cork, screw caps, and boxes. 

One of the biggest cons of using real cork to seal a wine is that the bottle may become "corked." Contrary to what I have heard from many people, a bottle being corked does not mean that pieces of cork can be found floating in the wine. In fact, typically when that happens, that is a wine service issue and not an issue with the cork, although with particularly old bottles of wine, properly pulling the cork to ensure no breakage can be exceptionally difficult. What does it mean for a wine to be corked? From a wine drinker's standpoint, it's best to explain with a story.

Back in 2005, when I was a well-read, but not overly knowledgeable wine drinker, I went to an unintentionally educational wine tasting. The wine rep who was serving had mistakenly grabbed one incorrect bottle. Rather than a weak vintage of one of his wines, he had grabbed a bottle a year older that was from a particularly desirable vintage. In fact, he didn't notice it until he picked up the bottle to uncork it. He explained to the crowd what he had done and that we were in for a special treat.

He poured the small tastings into the glasses of the 20 or so people and everyone in the crowd oohed and aahed. What an amazing wine. Well, almost everyone oohed and aahed. I signaled the wine rep over and said something was wrong with this wine. He smelled it and laughed. He said the wine was corked. What I had noticed was a musty smell almost like bad wet wood.

Clearly, a wine being corked is one of the cons of using real cork to seal a bottle. Surprisingly, some say that as many as 6% of bottles have some degree of cork taint although most mortal palates probably only identify about 10% of those.

Cork comes from the bark of the cork oak tree. And, for those that worry about how environmentally unfriendly that process might be, worry not. You see, the cork oak is one of the most resilient trees on earth. It's wonderfully flame retardant, tends to live for upwards of 300 years, and the bark itself naturally regenerates within about 7 to 9 years. However, the cork oak is susceptible to a fungus usually known as TCA -- (going from memory here) 2,4,6-trichloroanisole for the chemists in the room.

So, the only cons I can come up with of real cork are corking and crumbling. If you're at a restaurant and get a corked bottle of wine, send it back. The restaurant should get a replacement from their distributor, so they should not be bothered.

What are the pros of real cork? Cork is unique among woods in that it allows a wine to breathe. In other words, taking some liberty with the terminology, it allows the wine to keep its youth. If you like to age your wines, this is very important (for those of you who believe that a bottle of wine is meant to be consumed as soon as you get your hands on it, this is of no benefit to you). 

Synthetic corks are a relatively new phenomenon. Almost without exception, they are made from low density polyethylene (LDPE #4) and are recyclable. But, LDPE #4 does not allow the wine to breathe. Drink your bottles sealed with synthetic cork while they are young. And, if you do like to age your wines, just stay away from LDPE #4.

Screw caps have the same foible as sythetic corks, but they also have the significant advantage of being ridiculously easy to open, particularly if you've already had too much to drink. On the other side, however, and particularly if you have had too much to drink already, screw caps are made (for the most part of metal with somewhat sharp edges and they do cut fingers.

And, finally, there is boxed wine. I won't review any here, but some boxed wine is not bad. That doesn't mean I love it, but it's certainly way more drinkable than a corked bottle of wine. Again, the strange material that the wine "boxes" are made from is not ideal for wine storage. It leaks easily and it's just not cool or sexy. But, it too, is easy to open and easy to store until you finish it off in another hour in which case leakage just won't matter.

Ultimately, for most bottles for most consumers, the method of sealing just doesn't matter, but when you are drinking a great wine having laid it down for 7 or 10 or 20 or 50 years, you're less likely to be disappointed if it was sealed with real Quercus Suber L.