Chances are, when you\u2019ve ordered a bottle of wine at a restaurant, the server presented you with the cork. What should happen next is a source of some confusion and disagreement.\r\n\r\nTradition has held that you should inspect the cork. Indeed, there are two things you should look for. The first is that the cork, if branded, is from the correct producer and vintage as what you ordered. It\u2019s unlikely, but spotting fraudulent bottles is one reason that this ritual started. The second is to inspect the integrity of the cork.\r\n\r\nNext, many people believe that they are supposed to smell the cork. However, the topic is surprisingly controversial.\r\n\r\n\u201cSeriously, don\u2019t sniff the cork,\u201d advises one article. \u201cDon\u2019t smell the cork,\u201d\u00a0declares another. \u201cPut down that wine cork: Why sniffing gets you nowhere,\u201d opines a third.\r\n\r\nThe people who say you should not smell the cork are dead wrong.\r\n\r\nTo smell the cork is a vital part of evaluating a bottle of wine. It appears, however, that though the ritual has persisted for some, most people don\u2019t know why it began in the first place. Here is why you should sniff around every bottle of wine you open.\r\n\r\nA percentage of wines sealed with natural cork contain a contaminant called trichloroanisole (TCA), known as \u201ccork taint.\u201d Wines that suffer from this defect are referred to as \u201ccorked.\u201d This term is sometimes used erroneously for a wine with any fault, but should truly be reserved for TCA-tainted wines.\r\n\r\nWithout sniffing the cork, it\u2019s possible that everything will seem fine until 15 to 30 minutes later, when the taint starts to show.\r\n\r\nAt its most subtle, cork taint simply mutes the aromas and flavors of a wine. At its most overt, it gives the wine a strong aroma and flavor of a damp, moldy basement.\r\n\r\nWhen a server pours you a small amount of wine and you look at it, swirl it, smell it and subsequently taste it, cork taint is one of the things you are examining for. So why not just smell and taste the wine and skip the cork?\r\n\r\nHere is the thing: To the extent that the wine is tainted by TCA, the most likely source is the cork itself. This means the moldy basement aroma is often quite concentrated in the cork, whereas it might be less so on the wine.\r\n\r\nAdditionally, cork taint on a wine can start out as very subtle, essentially undetectable even by people who are highly sensitive to it. \u00a0However, as a wine is exposed to oxygen, cork taint can become more prominent.\r\n\r\n\r\n\r\nWithout sniffing the cork, it\u2019s possible that everything will seem fine until 15 to 30 minutes later, when the taint starts to show. If you are at a restaurant, you\u2019re now in an incredibly awkward position. You\u2019ve pronounced the wine sound, consumed some of it, but now have to tell your server that the wine is actually corked. Ugh.\r\n\r\nThis is where smelling the cork is your friend. It\u2019s your first shot to detect cork taint. About 90% of the time I come across a corked bottle, the taint is first detectable on the cork before being confirmed in the wine. While smelling the cork is not 100% effective at picking up TCA taint, in my experience it\u2019s still an extremely effective technique, even for wines that don\u2019t seem corked on first pour.\r\n\r\nIf you always smell the cork, you\u2019ll better educate yourself as to what cork taint smells like.\r\n\r\nIf you\u2019re having wine at home, smelling the cork can also save you from contaminating your glass with a highly corked wine and having to wash it out or grab a fresh one before moving on to another bottle.\r\n\r\nWriters have pointed out that smelling a cork is only helpful if you know what you\u2019re looking for. Indeed, many wine lovers don\u2019t know what cork taint smells like. But I believe this view is shortsighted.\r\n\r\nIf you always smell the cork, you\u2019ll better educate yourself as to what cork taint smells like. You will come across a cork that smells faintly, or perhaps strongly, like wet cardboard, and you can hone your skills from there. You may only pick up the more obvious examples at first, but subtler faults will become apparent over time. You\u2019ll also notice interesting variations in what different corks smell like.\r\n\r\nSo go ahead. Sniff away the next time a server presents you with a wine cork. There\u2019s a lot to learn from smelling that tiny piece of tree bark. Don\u2019t let anyone tell you otherwise.