Industry scientists are using knowledge about the codes for taste and smell to try to trick the sensory receptors and enhance the flavors of food, create more healthful substitutes for sugar and salt, or counter the bitter taste of medicines. Most current applications involve taste receptors, even though the olfactory receptors were discovered first, says Gary Beauchamp, Ph.D., president and director of the Monell Chemical Senses Center, a nonprofit research institute in Philadelphia.

"It was thought that once the receptors for smell were identified, they could be put into cell systems in the laboratory; then you could find out what compounds bind to the receptors, and this might be useful in designing odors of value. But it's been much more difficult to do than anyone would have guessed," Beauchamp says.

In early 2006, Monell scientists reported they had succeeded in maintaining rat taste receptor precursor cells in culture for up to two months and planned to try growing human taste cells in a similar manner. "This has the potential for practicality," Beauchamp says.

Senomyx, a California biotechnology company of which HHMI investigator Charles Zuker is a founder and Catherine Dulac is a scientific advisory board member, is developing several products aimed at the food industry. One, a spinoff of the discovery of the umami receptor, is aimed at creating a savory flavor-enhancing substitute for MSG (monosodium glutamate) and the company plans to sell it to China, which has the world's largest market for MSG.

The company is also at work on natural and synthetic compounds as high-potency sweeteners to reduce the need for high-calorie carbohydrate sweeteners in foods and drinks and on compounds that can block bitter receptors in taste cells.

"Blocking or modulating bitter sensation and taste could make otherwise unpalatable food sources such as soy protein more desirable, as well as medicines that leave a bitter aftertaste," says Zuker. Who knows—such a product might even lead to a cup of coffee with no bitterness, even taken black.

—R.S.