How Do We TASTE?

No, do not bite your little sister to find out. Instead, think about sweet hot fudge . . . salty, crunchy, munchy chips . . . sour, puckery lemons . . . a juicy, meaty hamburger . . . and (yech) bitter brewed tea. From these five basic tastes-sweet, salty, sour, savory, bitter-come all the flavors that we humans know and love (or hate). But how do we taste them?

It all starts with your tongue. Check out your tongue in a mirror and notice its soft, velvety texture. Look more closely and you may see that it is actually covered with tiny points of flesh that give it a kind of shag-carpet look. Scattered around, mostly at the front, along the edges, and toward the back, you may see little bumps in various shapes. Inside these bumps are your taste buds, each one a collection of cells that are specially equipped to pick up the sweet, sour, bitter, savory, or salty flavors of the food you are chewing. (You also have taste buds on the roof of your mouth and inside your cheeks.) Humans are born with about 10,000 of these tiny taste-bud sense organs, and they work so hard that your body replaces them about every two weeks.

Other Taste Buddies

But taste buds don't do all the work. Suppose you are enjoying a spoonful of peanut butter. Remember that shag carpet on your tongue? Each of those tiny tabs of skin is actually designed to help your tongue feel the food in your mouth. They signal wildly to your brain about the thick, smooth, sticky substance that covers them. As you chew, the saliva in your mouth begins to digest the peanut butter with a special chemical. Soon, nothing remains but microscopic particles of peanut butter. These come into contact with your taste buds, where special cells identify the taste of salt and the sweet taste of sugar (which are usually added to peanut butter). Nerves send this information on to your brain. At the same time, molecules carrying the fragrance of the peanut butter waft up through your nose, and scent detectors report the smell to your brain. Almost instantly, your brain gets all these messages and interprets them to recognize the flavor. WOW, it says, PEANUT BUTTER!

Flavor Wizards

Who puts that cherry flavor in a lollipop or the cheddar-cheese tang in a potato chip? Rest assured, teams of highly trained food chemists known as flavorists toil night and day to bring you all the flavors you crave.

In the lab, flavorists work with hundreds of extracts, powders, and chemicals, some so strong that one drop could flavor an entire swimming pool. Like wizards concocting magic potions, they carefully mix 30 or 40 ingredients together, sniffing along the way, until they smell the perfect blend. (Since a flavor is determined mostly by its smell, the flavorists start with the aroma and then tweak the taste.) The flavor can then be applied to chips or ice cream or frozen dinners. After years of such work, flavorists develop finely tuned senses of smell and taste, and like artists, they take pride in their creations. To keep the competition away from their latest banana-barbeque-butterscotch brew, each flavor formula remains top secret.

The combination of these characteristics-a food's basic tastes, the way it smells, and the feel of it in your mouth, along with its temperature and appearance-gives the food you eat its flavor. Believe it or not, smell accounts for about 85 percent of how something tastes. If you try to eat your peanut butter sandwich while you are holding your nose (which isn't easy), you won't taste much.

Why Taste at All?

Why is the tasting process so complicated? Just so we can enjoy our food? There's more to it than that. In all animals, including humans, tasting does two important jobs: it warns us about bad foods and it attracts us to good ones. When our ancient ancestors roamed the forests and fields, hunting and gathering their dinner, they needed a way to tell poisonous plants from healthy ones, or whether a piece of meat was spoiled. In general, toxic plants have a strong bitter flavor that both animals and people know to avoid. Because the taste buds on the back of the tongue are most sensitive to bitterness, even if you start to eat something bad, you have one last chance to gag and spit it out before you swallow. Similarly, spoiled food often tastes sour, warning us not to eat it. Sourness can also mean a food is not ripe and therefore not good to eat.

On the other hand, foods that contain certain amino acids, which are the building blocks of the proteins that our bodies require, have a savory, sort of meaty taste that humans like. Likewise, a pleasant, sweet taste is common in foods that are high in calories, which we need for energy. Early humans learned that sweet and savory tastes meant healthy foods. As a result, we still favor these tastes today. Indeed, human babies are born with a taste for sweetness to make sure that they will eat their first food, milk, which contains natural sugars.

Good Taste-Bad Taste

The world is full of wonderful things to eat. You probably have favorite foods and others you aren't so fond of. You and your best friend may disagree about what's better: chocolate mint ice cream or caramel vanilla. Why do our tastes differ so much? Tongues and taste buds are all the same, right? And the real stumper: Who does like the taste of broccoli anyway?

As scientists try to figure out how our sense of taste works, they are discovering that different people probably taste things differently because they have more or fewer taste buds. Most people, with an average number of buds, are medium tasters and enjoy a range of flavors and foods. (They, most likely, enjoy broccoli.) Certain people can't taste at all, which means that they probably don't enjoy eating anything and so may not be getting enough nutrition through their food. Their tongues have as few as 11 taste buds per square inch.

A third group of people are known as supertasters. These individuals can have 100 times more taste buds per square inch than nontasters do. This makes them extremely sensitive to certain tastes, and even temperatures, of food. Supertasters don't usually like spicy foods, and bitter or sour foods can have a very strong or unpleasant taste to them. Sweets may be just too rich tasting. Supertasters may not enjoy healthy foods such as grapefruit, broccoli, or celery because the taste is too strong.

But don't worry; a little salt can make even supertasters enjoy their broccoli.

Copyright Carus Publishing Company Nov/Dec 2004
Provided by ProQuest Information and Learning Company. All rights Reserved