How Do You Know a Wine Is Corked (& How Do You Send It Back)?
Conservative studies estimate that 5 to 6 percent of bottles are affected by some sort of wine defect. That's roughly one in 20bottles.
Photo by Jeremy Parzen You can't tell if a wine is "corked" by looking at the cork. The cork is often presented not to evaluate the wine's fitness, but rather to determine the authenticity of its provenance.
The most common defect is TCA, otherwise known as trichloroanisole, "a potent taint compound associated with musty odours and flavours in a range of food and beverages," according to the editors of the Oxford Companion to Wine.
Some tasters will describe the presence of TCA as "musty" or "wet cardboard." Sometimes it just smells like rotten cork. In most cases, it's unmistakable. But it can also be so faint that even professional tasters (like the ones in the anecdote above) won't immediately notice it.
Some in the wine trade estimate that roughly 50 percent of wine defects are traced to faulty corks. Keep in mind: A cork wine closure is made from the bark of a cork tree, and because it is an organic substance, it is susceptible to a wide range of issues (with TCA being the most common).
But wine defects can also be ascribed to a number of different causes, often originating at the winery or occurring during shipping and storage.
One of the most common is volatile acidity: an acetone "fingernail polish" odor that masks the wine's fruit aroma.
Another is maderization (from the wine name Madeira), whereby a wine is oxidized (exposed to oxygen due to a faulty seal) and possibly cooked (due to exposure to extreme temperature). In a maderized wine, the fruit flavors will be attenuated or entirely absent.
Evaluating the fitness can be one of the most divisive and contentious issues among wine professionals and consumers (especially when the wine in question is an expensive one).
Here are some rules of thumb for determining whether or not a wine is correct:
Make sure the glass isn't tainted by detergent residue or dust.
This is a major problem in restaurants, where wine glasses are often cleaned in dishwashers using reclaimed water. It's also a big issue at home, where wine glasses often collect dust when not in use. (See this post on priming your stemware.)
Give the wine a healthy swirl and then stick your nose into the glass.
You should be able to tell whether or not the wine is correct by smelling it. The first thing to note is the presence or absence of fruit aromas. Wine is made from fruit and it should smell like fruit. If you don't detect any fruit aromas or you detect a foul aroma that masks the fruit, you most likely have a corked, oxidized or maderized wine.
Take your time when evaluating the wine.
In more cases than not, foul odors will "blow off" after a few minutes. They're often due to "reduction," a phenomenon whereby the wine has not been exposed to enough oxygen during aging. It might smell like a fart, and it will probably go away after a few minutes. Give the wine some time to "open up" in the glass before you determine whether or not it's corked or otherwise defective.
Remember that there is a big difference between a wine that is corked and wine that you simply don't like.
Just because you don't like the wine doesn't mean that it's corked or faulty. Before you order or purchase a bottle of wine you've never had before, consult with your server or wine salesperson and let him or her know what kind of wine you like. If ordering a bottle of wine that you already know, you should have a recollection and expectation of what it should taste like. If it smells or tastes radically different from the way it has in your past experience, it might be faulty.
So how do you send a bottle back when you think it's corked? I'll address that extremely sticky issue in next week's post.