The Physiology of Taste
Taste is arguably subjective when art, fashion, or music is the subject of conversation. When wine is the subject, you will find that everyone may have different “tastes” in wine, but tasting wine has an objective component. For one thing, tasting wine (or anything!) involves not just taste, but sight, smell, and touch. These fours senses send objective information to your brain, and this helps you evaluate, not merely appreciate, that glass in front of you. Whether you like what your brain is telling you, that is where subjectivity enters the picture. What you like is very much tied to your upbringing and cultural influences.
Whether you are evaluating wine or appreciating wine, setting is enormously important. That incredible bottle of Chianti you shared over a romantic dinner didn't measure up when you drank it alone in front of the TV, did it? Your taste is affected by your mood, by your health, and by your environment. Try to enjoy a floral Viognier when you have a cold or when you're in a smoke-filled room. It will be quite a challenge.
Individuals have genetic differences that determine their ability to taste. People can be divided into categories of supertasters, nontasters, and normal tasters. Supertasters are especially sensitive to sweetness, bitterness, and the creamy sensation of fat. Apparently, they have more taste buds than everyone else — as many as a hundred times more than nontasters. About 25 percent of the population are supertasters, and two-thirds of all supertasters are women.
Sight
A wine's appearance influences your judgment. Color and clarity are the key things to look for. Is the color what you expected, or is it somehow off? Is clarity lacking because of any cloudiness that would indicate the wine is unfined? Are there any perfectly harmless tartrate crystals in that glass of white wine? In blind wine tastings, participants are sometimes given black, opaque glasses so they're not prejudiced by what the wine looks like, even by the color.
Color can tell you something about the age of wine. As white wines get older, they get darker. As red wines age, they lose color.
Smell
Your sense of smell is your most acute sense and is many times more sensitive than your sense of taste. You sense aromas either directly by inhaling through your nose or, indirectly, through the nasal passage at the back of your mouth. Taste and smell are so linked that when you experience the generous dark fruit of a Cabernet Sauvignon, you are actually tasting aromas of that dark fruit.
Speaking of fruit, don't be surprised if you think of blackberries as you smell your Cab. Wine is made up of hundreds of chemical compounds, many of which are similar — or identical — to those in fruits, vegetables, flowers, herbs, and spices. The winemaker did not add essence of blackberry to that wine; your brain is simply picking up one of those compounds.
Taste
In contrast to the multitude of aromas the nose can identify, the tongue recognizes only four basic tastes: sweetness, saltiness, acidity, and bitterness, and some might say umami. Saltiness doesn't come into play when tasting wine, but the others are critical. The tongue does not register these four or five tastes at distinct sites as was previously thought. It has been proven that taste occurs everywhere on the tongue.
When tasting wine, never judge a wine on the first sip. Your mouth must first adjust to the alcohol and acidity before it can more accurately convey that wine's other attributes. It's also better to taste before lunch or dinner, not after. Your senses heighten as you get hungry.
Sweetness and acidity are the yin and yang of the winetasting world. They balance each other. Think of lemonade. Lemon juice on its own is a mouth-puckering experience. The more sugar you add to the juice, the less you notice the acidity.
Bitterness plays a role in winetasting as well. Red wine tannin, while having more of a tactile nature than a taste, can give you the impression of bitterness.
Touch
Wines have texture that you can feel in your mouth. A wine can be thin — like water. Or it can be full — like cream. That's what a wine's “body” is all about. “Full-bodied” and “light-bodied” are not subjective judgments; they are descriptions.
Your mouth distinguishes other sensations as well. Tannins, the elements responsible for a wine's ability to age, have an astringent, mouthdrying effect very much like the impression you get when you drink oversteeped tea. The alcohol in the wine will give you a hot feeling at the back of your throat and on the roof of your mouth.
Your perception of a wine's body — its texture and fullness — is due mostly to the amount of alcohol in the wine. The more potent a wine is, the more full-bodied it will seem. For example, a big Zinfandel with 16 percent alcohol content will have more body than a Riesling with 9 percent.
