Tuesday, March 27, 2007
An ingredient of a plant used for centuries as a medicinal herb in India can block receptors in the mouth from tasting sweet foods. Using a concentrated form of this ingredient, a company has developed a tablet that, when sucked or chewed, rapidly makes all sense of sweetness disappear for up to 30 minutes.
Why would someone want sweetness out of their lives, even temporarily?
George Kontonotas, president of Genotec Nutritionals Inc. in Commack, N.Y., says it helps overweight people resist sugary snacks and removes the sweet taste from tobacco smoke.
He says cigarette manufacturers put at least 20 substances into cigarettes, including cloves and apple juice extract, to make smoking more palatable. When sweet receptors on the tongue cannot sense those tastes, "the true taste of tobacco is awful."
The taste-blocking effects of the active ingredient, gymnemic acid, have been known for some time, but the herbal tablet was introduced to stores in New York just last month.
"It is true that this substance blocks sweet tastes," said Lawrence Marks, a professor of epidemiology and psychology at Yale University and director and fellow of the Yale-affiliated John B. Pierce Laboratory. The herbal substance, he added, "appears to be safe." But as with every substance, moderation is the key, he said.
Taste science is big business, said Danielle Reed, an associate member of the Monell Chemical Senses Center in Philadelphia who helped identify sweet receptors in 2001. There are five families of receptors that respond to taste: sweet, bitter, salty, sour and savory, the stuff of MSG.
Gymnemic acid seems to impede sweetness perception by blocking the signals that go from the receptors on the tongue to the brain.
Several plants play similar tricks on the senses. Linda Bartoshuk, a professor in the college of dentistry at the University of Florida, worked on an African berry called miraculin.
Initially, the berry was thought to turn sour into sweet. But Bartoshuk proved that it actually made any flavor taste sweet. People called it the Miracle Fruit, but efforts to commercialize it were not successful.
Genotec Nutritionals calls its herbal preparation Sugarest. It can be found in other supplements as a diet aid to control blood sugar, said Joseph Freedman, head of research for the company, but Genotec is the first to use it in a concentrated dose to block the taste of sugar.
"People think it's a parlor trick," Freedman said. Receptors on the tongue for salty, sour and bitter are not affected. In other words, a pretzel still tastes like a pretzel. ·