All about the cork

It may well be the least exciting and uninteresting part of learning about wine, but come on, if that little piece of tree bark wasn’t shoved in the bottle what do you think would hold in all that juice you inevitably want to get at? Screwcaps? They are out there. Pieces of leather covered with a wax seal? It’s been done before (150 years ago). So realize, it’s all about the cork my friend.

Corks have hundreds of years of history behind them as bottle stopping devices. They have the ability to compress and expand, they transmit no flavor into the liquid (unless tainted), and with it’s elasticity can (while moist) keep an air tight seal for decades in a bottle. The cork is made from the bark off a type of oak tree found in Spain and Portugal known as Quercus suber.


This tree has a long maturing process before it can produce a cork that is of a high enough standard to be used in a bottle of wine. The tree will be around 25 years old before it is stripped of it’s bark (this doesn’t hurt the tree, it has two layers of bark) for the first time, and the cork from the initial stripping is not used for bottle stoppers due to it’s lack of quality, only the best for YOUR wine.

Then after 9 long years of regenerating the outer layer of bark, the tree will be stripped again. Now the cork may be of a high enough quality to be used for a bottle stopper, and all are graded and sorted depending on quality, with the corks at the top of the class going to the finer wines with aging potential. These trees produce many 9 year cycles of strippable outer layers of bark, and are each specifically marked and numbered so they are each given another 9 years until the next harvest. The Quercus suber goes through this process for about 150 years. That’s a lot of cork.

It seems as though it is a match made in heaven, the combo of wine, cork and glass bottles. However many wine-tasting experts are sticking to their claims that as many as 6–10 % of wines from around the world are tainted and spoiled because of the cork itself bringing a chemical compound to the once perfect wine. This is known as a “Corked” bottle, and many wine drinkers are familiar with the term, and the consequences. The consequences are that the bottle you were going enjoy is now unenjoyable. The wine now has a musty, wet cardboard, old soggy newspaper smell and taste to it, and that just can’t be good for your $50 bottle of Chardonnay you just opened for a special occasion.

The combination of chlorine, moisture and mold held within the cork has caused a condition known as 2,4,6-Trichloroanisole or TCA. Lets stick with calling it TCA. The chlorine has been used in the cork cleaning process earlier in the little corks life, and now with moisture and certain molds, there goes another bottle tainted again. Maybe $8 of undrinkable wine or maybe a $280 bottle, corks don’t care.

My own experience with tainted bottles of wine and faulty corks have been few and far between, I have opened and poured 1000′s of bottles and have definitely had dining guests that were not familiar with the wine being served and probably thought that was how that wine was supposed to taste. Some of the tainted bottles are less severe than others, so I can see where it could go unrecognized or unchallenged by a guest. Some may think this sure is a fruitless, bland, kind of unpleasant musty wine, but hey, it is French, so I better just grin and bear it. Another tainted bottle down the hatch without anyone keeping a tally.

At the large tastings with 100+ wineries pouring their product to a wine knowledgeable crowd, a corked bottle will be called out right away. Sometimes a little too loud, as if the winery representative had a part in the conspiracy to pour bad wine. That wine will be tasted for a second opinion and placed right under the table as if nothing ever happened, making this another scene with no tally taken.

So the inside scoop comes from the professional tasters and wine writers with a budget who have the luxury of weekly and monthly sit down tastings from 10 to 100 bottles at a time. They make serious judgments on every wine and the tainted wines are easily identified and tallied. If they say 1 in 10 bottles are effected, I’ll go with them on that. I must be lucky not to run into them that often in my personal wine drinking.

The cork industry however, absolutely thinks that these numbers are unrealistic and bash the good, honest corkers. The cork producers are able to admit to about 1-2% of wines becoming tainted due to tarnished corks.

It’s just a fact of wine drinking life, but it is costing consumers money, from occasional drinkers, collectors and everyone in between. Reputable wine merchants will replace the bottle and most restaurants also.

Many people want change, and the synthetic cork industry is ready to oblige. There are a few manufacturers out there now that are producing these plasticy, rubber corks that are made from ethylene vinyl acetate. Some come in cork camouflage colors while others are orange and purple and scream “Look at me, wine snobs, I’m not cork”. If these synthetic corks can eliminate TCA in wine, and will not crack or break in half if opened wrong, then they might have a following one of these days.

Another benefit to these synthetics are that they do not need moisture to create an air tight seal, therefore the wine does not have to be placed on it’s side to keep the cork moist and the air tight seal perfect. Many wine merchants keep the wine standing up on the retail shelves for far too long. I have seen bottles standing for a month, this will dry out the cork, let some air in, and oxidize the wine.

Real cork however is not going anywhere for now, it will take decades to see if wineries old and new are ready or willing to change over. The synthetics have to prove that over long periods of cellaring they do not impart any flavor or residue, and have the ability to keep a perfect airtight seal.

One more alternative is the screwcap. A hundred dollar bottle of fine wine with a Mad Dog 20/20 screwcap? That’s right, and it’s airtight. Plumpjack winery in Napa Valley is already onto it because they are tired of the high spoilage rate of cork. Their 1997 Reserve Cabernet Sauvignon will be released with a screwcap retailing at $135 a bottle, and they will also bottle some with the traditional cork retailing for $125 a bottle. These guys are cutting edge for a winery that produces fine wine, and are the first premium winery to do so. I bet it flies off the shelf. Think of the $10 you could save on a corkscrew.

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