Wine service can feel intimidating if you’re not experienced with the ritual. The swirling, sniffing, and polite approval after that small initial pour might seem like theater or a simple taste test. However, that preliminary sample serves a specific purpose: verifying the wine’s quality.
The initial pour allows you to detect whether the wine has spoiled. Bottles can deteriorate due to poor storage conditions or defective corks, resulting in what’s known as “corked” wine. This flawed wine typically emits musty odors reminiscent of wet cardboard or mildew, and tastes nothing like the winemaker’s vision. A quick aroma check before tasting helps identify problems before the server pours the full glasses, protecting your investment — no matter how large or small.
Because of that, you don’t even need to sip the wine, but it’s fine if you do. If you want to show you’re a wine drinker in the know, though, simply give it a big swirling sniff, since a bad bottle is usually detectable by smell alone. But that flex is valuable only if you know how to sniff out a bad bottle.
An estimated 1% to 7% of bottles are corked — we’ll explain what that means below. Knowing what to look, taste and smell for is key when scrutinizing wine for problems. To get the full scoop on corked wine and how to tell a good bottle from a bad one, we turned to the experts. Here’s everything to know.
What is corked wine?
“A corked wine is caused by a compound called trichloroanisole, or TCA, which contaminates the cork, bottle or wine itself during harvest, production or even shipping,” said Vinnie Miliano, bar manager for the famed Waldorf Astoria Chicago.
Corked wine can come from a restaurant wine cellar or your own collection.
TCA often exists as fungi in corks but can also present itself in pesticides, preservatives and cleaning products found in wineries. Barrels and cardboard boxes can also be sources of “contamination,” even if high-quality control standards have been rigorously implemented.
“A corked wine isn’t harmful to consume, but it certainly isn’t pleasant to drink and will definitely detract from the experience,” Miliano said.
Despite the temporary awkwardness and disruption of dinner service, it’s OK to send something back that doesn’t taste up to par. After all, if you’re shelling out hard-earned cash to treat yourself and a loved one, you don’t want the evening to go, well, sour.
We asked Miliano, as well as Courtney Cheney, the beverage operations manager for Ocean Prime, to explain how to tell if a wine is corked and the proper protocol of flagging the issue with a sommelier or server. (For more wine tips, read a sommelier’s best tips for finding budget bottles and see how to properly store every type of open wine.)
How to tell if a wine is corked
Corked wine may smell like musty like wet cardboard or a damp basement.
There are typically two immediate indicators to detect if a wine has been corked: aroma and taste. “A corked wine will typically smell off, with scents of wet cardboard, mustiness, or like a damp basement,” Miliano said. “If you taste it, you’ll notice the taste can be muted or unpleasant, lacking the expected fruit and structure.”
Cheney echoes these exact descriptions, adding that a corked wine will also taste “flat with a distinct astringency in severe cases that will also lack fruitiness.”
And while one may believe that some tannin-heavy varietals are more prone to corking than others, TCA doesn’t discriminate. “It is easier, however, to recognize cork taint in wines that are unoaked, due to more powerful aromatics that accompany oak aging,” Cheney said. “It’s [also] more likely to occur in wines with traditional corks.”
Read more: We Asked a Wine Pro if Open Red Wine Lasts Longer in the Fridge
How to send back corked wine
Don’t be shy about sending back a corked bottle of wine.
Should you stumble across a corked bottle, a trained wine professional or bar manager will likely remedy the unfortunate circumstance. “The best approach is the simplest,” Miliano said. “Politely inform your server or sommelier. There will be no offense taken, and most hospitality professionals are trained to handle the situation gracefully.”
This may include tasting the wine themselves before replacing the bottle or glass. If you’re not entirely sure, you can also rely on their expert palates for an explanation and/or final confirmation.
“I once had an entire case of wonderful Rioja completely corked,” said Miliano, who also says that there is no need to “feel embarrassed or angry” in the moment. Quality verification is merely part of the process and an important step to determine if additional inventory is affected.
“You can also check the cork, which should be presented to you upon your server opening the bottle,” added Cheney. “If it smells musty and dank, it is likely corked.” Of course, if there is any type of pushback, escalate it higher to restaurant managers or owners after your meal. This can be done via email to avoid confrontation.
Read more: 7 Surprising Recipes You Can Add Wine To
Nothing to wine about
Any restaurant worth its salt will replace a corked bottle with a good one free of charge.
Cheney wrapped up the concept of wine corking best: “Cork taint is a naturally occurring fault in wines, so most restaurants will replace the bottle without further question or charge.”
While an offensive sip may be unlucky, remember that it’s probably the worst thing that will happen to you that day. Accept it, say something about it and move on. It’s nobody’s fault (not even the winemaker’s), and you more than deserve a stress-free, delicious meal that’s worth every dollar you spend.
