Throughout the country, people are chewing watermelon gum, applying strawberry-flavor lip balms and eating fruit-flavored candies. At the movies, Americans munch popcorn drenched with artificial butter. And at the supermarket, there are so many flavored seltzers it is sometimes impossible to find the plain kind.
The number and range of artificially flavored products is so enormous that some wonder whether or not Americans will lose their taste for the real thing.
"We are continually confronting our palates with intense, artificially flavored substances. I worry that we may be overwhelming our palates, diluting our ability to taste real food," said Audrey Cross, an associate professor of nutrition at the Columbia School of Public Health.
"If a child grows up thinking that the Jolly Rancher's palate of flavors like cherry and watermelon is what those fruits taste like," she added, "when they taste the real thing, it doesn't taste right."
Physiologically, people can discriminate among a wide range of flavors, according to Carol Karahadian, the manager of sensory evaluation at Firmenich Inc., a Princeton, N.J.-based company that sells flavors and fragrances. People build a huge flavor library in their brains, so chewing watermelon gum doesn't eliminate the possibility of appreciating watermelon, but just adds another flavor to the files.
But, while a steady diet of intense synthetic flavors does not appear to affect the ability to perceive flavors, it may affect preferences.
"If people never or rarely taste fresh raspberries, then they begin to accept the artificial flavor, because that is what they've been exposed to," said Barbara Klein, professor in the department of food science and human nutrition at the University of Illinois at Urbana-Champaign. "When given a choice between fresh and artificial raspberry flavor, I suspect they might choose the artificial if it is more intense. There is an expectation of that intensity."
Does the natural taste of foods pale by comparison? No one really knows. Certainly, the diminishing range of natural flavors due to greater centralization of agriculture will not help people understand the subtlety and nuance that is possible.
There is a "homogenization of flavors," according to Adam Drewnowski, director of the human nutrition program at the University of Michigan in Ann Arbor.
"What is the flavor of wild strawberries or of the various varieties of apples?" he asked. "We don't know because we don't eat them. We eat Golden Delicious and McIntosh."
People also chew apple-flavored gum, and drink apple juice, both generic-tasting. What we get, he added, are "the three dominant notes in our cuisine: fat, sugar and salt."
There are two components to flavor, taste and smell.
People are born with the ability to taste sweet, sour, bitter and salty. The olfactory system lets them perceive an assortment of other flavors. This is why flavoring is complicated.
"Most odors are made up of many components, and changing them or changing their proportions will change the odor," said Susan Brewer, associate professor in the department of food science and human nutrition at the University of Illinois at Urbana-Champaign.
"The real Chanel No. 5 is very different from the imitation. Often to get a real fix on what it takes to make a particular odor is not all that easy."
This is why some artificial flavors are so strong. "In some cases, when you can't produce a flavor that is really like, say, watermelon or pineapple, one technique is to jolt up the intensity a bit," Brewer said.
Certain types of product may require more intense flavoring.
"One factor is time," Brewer said. "When do you sense it? How long do you sense it?
"Take chewing gum. You could be chewing for a couple of hours. Does it still taste after two hours? It's different from something you eat quickly."
The temperature at which one eats a product, how much fat, salt and sugar it contains and its texture also affect how intense the flavoring must be.
Along with intensity goes sweetness.
"With many of the flavored products, like flavored waters," Cross said, "they add not just orange bitters, but also sweeteners, partly for practical reasons. When you add sugar it does more than sweeten. It adds shelf life and it's inexpensive, so the manufacturer gets several edges."
Many factors drive companies to use artificial rather than natural flavorings. Cost is one, and synthetic flavors can be engineered to be fat- or water-soluble, an important distinction, depending on the product to be flavored.
Another advantage of synthetic flavors is product consistency. Not only is it difficult to figure out the intensity of a natural flavor, but it can also be troublesome to maintain it at a consistent level. With artificial flavoring, it is easy.
Because there is variation in what people taste, companies use taste panels to test new or reformulated products. These are groups of consumers who evaluate aroma, flavor and whether or not the item is a desirable product.
"When you train people to be on taste panels, what you're looking for is to match some kind of standard you provide them," Klein said.
"Normally, that is some kind of controllable substance. So we might take the dominant flavor component of, say, cherries, and we'd use a known concentration of that component and use it as a standard. That flavor has none of the nuances of real fresh cherries, but we use it because it's a controllable substance--we can say how much is in the solution on a 10- or 15-point scale."