IT'S THAT OFFICIAL kissing time of year, a reminder to give thanks to tongues. Ah, the tongue. An encomium to this matchlessly versatile anthology of muscles can head in any number of directions, most of which I will leave, dear reader, to your imagination. I pity the shark, whose tongue (called a basihyal) is an unlively piece of cartilage that lies uselessly on the floor of its maw.

For most animals, including humans, the tongue is the vehicle for taste buds (although butterflies, suitably, have taste buds on their feet). Dab some blue food coloring on your tongue, and your taste buds will become visible as pale bumps scattered over the tongue's surface – like stars in a midnight sky. These are not, strictly speaking, your actual taste buds (which can only be seen under a microscope) but the conglomerations of tissue – papillae – that bear them. Taste buds are bundles of cells and nerve extensions, packed together much like a peeled orange, with an opening at the top (the taste pore), which, with the help of hairlike microvilli, receive chemical signals from molecules of food – or whatever is in your mouth. Your brain then translates the signal into one of what are now widely accepted as five basic taste sensations: salty, sweet, sour, bitter, and the recently acknowledged umami. Umami, a Japanese word that roughly translates as tasty, is the sense for glutamate and monosodium glutamate (a.k.a. MSG) in particular. Turns out glutamate is found in many delicious things – tomatoes, meats, and aged cheeses (such as Parmesan), to name a few.

The average American adult has 10,000 taste buds – mainly on the tongue but also scattered around the mucous membranes of the mouth, especially the roof, and the top third of the esophagus, so you can taste what's going down. The tip of your tongue has the buds that are most receptive to sweet, the sides recognize sour, and the back gets stuck with bitter. Salty seems to be all over the place, though some say the sides of the tongue are particularly receptive. Science has divided humans into supertasters, medium tasters, and nontasters. About half of Americans fall into the medium taster category – i.e., average. The lucky supertasters, on the other hand, have a higher concentration of a specific kind of papillae (fungiform) than their less super compatriots. Supertasters are especially sensitive to sweet and bitter, as well as to spicy foods, the "mouth-feel" of fats, and the burn of alcohol. Curiously, a study showed that women who are supertasters aren't fond of fat or sweet, while men supertasters are. According to Dr. Bartoshuk, a taste researcher, most supertasters are women, at least in the Caucasian population: 35 percent of women, and only 10 percent of men. Poor nontasters get the short end of the receptor cell, so to speak. A nontaster, for example, may barely react to the sweetness of a cookie that a supertaster finds unpalatably sugary.

Want to know where you fit? Here's a test from Dr. Bartoshuk to determine whether you're a nontaster or a supertaster: taste postassium chloride (it's a salt substitute, but I have no idea where you'd find it) and saccharin, respectively. To a supertaster, both will taste bitter; to a nontaster, neither will. A more complicated experiment involving blue dye, gummed rings, and a magnifying glass can be found here.

The least understood of the senses, taste probably has the most market-driven research devoted to it, as the food industry tries to discover what will sell. Although umami is the latest sense of taste (it was accepted in the late 1990s), new studies show there may be a taste sense for carbohydrates and even one for fat, which was long thought to be only a carrier for flavor. Tasting abilities are mainly determined by heredity and may serve as both indicators and determiners. There is a potential link between nontasting and alcoholism. Studies show that alcoholics tend to be nontasters and that nontaster alcoholics often have a serious sweet tooth. On the deterministic side, supertasters are generally slimmer than medium or nontasters, likely because they get more satisfaction out of less food. What role culture plays in taste sensation is not clear. Some aspects of nurture (or lack thereof) are evident; smokers, for example, have fewer taste buds, and we lose taste buds as we get older.

But the tongue doesn't deserve all the credit for taste. Hold your nose as you eat something; a friend tells me an onion will taste just like an apple if you do. (I haven't been able to bring myself to try.) The nose is an equal protagonist in our recognition of flavors. Flavors result from the melding of the various taste senses and the reactions of olfactory receptors, which tie into the feeling and memory parts of the brain and make our experience of food, uh, memorable. Perhaps if Proust had had a cold the day he dipped a madeleine in his tea, we'd be a few thousand pages bereft today.