Most wine drinkers are probably familiar with the term 'corked wine', but I hazard a guess that not as many wine drinkers really know what a corked wine tastes like, how a wine becomes corked in the first place, or how to detect a corked wine. Read on to find out more about corked wine — how it happens, and what it tastes like.
How a Wine Becomes Corked
A corked wine does not mean a wine that has tiny particles of cork floating around in the glass. Corked wine is a term for a wine that has become contaminated with cork taint. Cork taint is not simply the taste of a cork. Rather it is caused by the presence of a chemical compound called TCA (2,4,6 - trichloroanisole). TCA is formed when natural fungi (of which many reside in cork) come in contact with certain chlorides found in bleaches and other winery sanitation / sterilization products. If a winery uses infected corks, the wine becomes tainted. If let loose TCA can contaminate not just a single batch of corks (and wine) but can infect an entire cellar or winery. Once entrenched it is very difficult to eradicate. Since the discovery (only as recent as the early 1990's) of the cause of cork taint, most wineries have totally eliminated the use of chlorine based clearing products.
The Taste of Corked Wine
While unpleasant to taste, cork taint is not in any way harmful to humans. Corked wines smell and taste of damp, soggy, wet or rotten cardboard. Cork taint dulls the fruit in a wine, renders it lackluster and cuts the finish. The obviousness of the corked smell and taste depends both on the extent of the taint, as well as the wine drinker's sensitivity to it (aka your cork taste threshold). Sometimes it is barely noticeable and other times it knock your socks off the moment you open the bottle. For example, while I am the wine professional in our household it is my husband who can smell the corked wine almost before the cork has been pulled, no matter how slight the taint.
All through the 1990's and early 2000's it was believed that the incidence of cork taint was as high as 7-8% of all wines bottled under cork. The rise in popularity of screw-caps and other alternate closures was in no small way attributable to the incidence of corked wines.
The Cork Industry's Response to the Problem
It is unlikely that the problem potential can ever be totally eradicated, but after a period of sticking their heads in the sand and ignoring the problem, the key players in the cork industry did set about finding a solution and today several advanced QA/QC procedures and treatments are in place to render cork less susceptible to developing cork taint. But it can still happen. Remember, we are talking about natural fungi which are everywhere, and of course various chemical reactions.
Cork: Wrongly Blamed for Other Wine Faults
Unfortunately, because the term 'corked wine' is more familiar to wine drinkers than the names of other wine faults, wines are often declared corked, when in fact the culprit is something entirely different. (Look for more on other common wine faults in a February post.)
Can I Bring or Send Back a Corked Wine?
If you discover that a wine you just opened is corked you have the right to bring or send it back. Retailers generally do not question it when you return a corked bottle — although it is best if the bottle is not almost finished!
In a restaurant, the same logic applies, however sometimes it can be a little more difficult or sensitive. If you are not used to looking for faults in wine, you may feel intimidated and not detect the taint when the sommelier or waiter first asks you to taste the wine. It may take ten to fifteen minutes for you or somebody in your party to question the wine. If this happens, my advice is to call back the waiter and explain, asking him or her to taste the wine. If the wine is indeed corked it should be immediately obvious to the sommelier.
Cork Taint: Increasing or Declining?
While I have not carried out any comprehensive or scientific study, from my own experience I have to say, that the problem does not seem as extensive as it did 8 to 10 years ago, when almost one in five bottles I opened was tainted. I open quite a few wine bottles every week, and these days it is often several weeks before I find a tainted wine.
I would love to hear from readers on your questions and /or experiences with corked wines.
Until next week, stay away from corked wines!
Mary Gorman-McAdams, MW (Master of Wine), is a New York based wine educator, freelance writer and consultant.
Related: Is Cork the Best Wine Stopper?
(Image: Faith Durand)