Dieting leaves a bitter taste no more

Dieters can be left with a bitter taste in their mouth when switching from sugar to artificial sweeteners like saccharin and acesulfame K, but this taste could soon disappear along with their extra weight after scientists discovered a chemical that specifically blocks people’s ability to detect the bitter aftertaste.

The key molecule – known only as GIV3727 – specifically targets and inhibits a handful of human bitter taste receptors and opens the door to further discovery of compounds for other taste-enhancement purposes, like hiding the taste of medicines and other bitter flavours.

“To our knowledge this is the first published example of a bitter receptor inhibitor with taste activity in humans,” said Jay Slack of Givuadan Flavours Corp, “We applied high-throughput screening and medicinal chemistry approaches to develop specific inhibitors for human bitter taste.” The study was undertaken with colleagues at the German Institute of Human Nutrition Potsdam-Rehbrüke, the Institute of Chemistry at the Romanian Academy and the University of New Mexico.

The researchers screened the activity of thousands of molecules against human bitter taste receptors, and specifically those that responded to saccharin. These methods are commonly used in developing new drug candidates, but this is the first time such methods have been applied to bitter taste modulation.

GIV3727 was not previously known to have any particular taste properties, but in fact has been shown to work on five other human bitter taste receptors.

In controlled human taste tests, almost everyone selected the beverage containing GIV3727 as being less bitter and the presence of GIV3727 didn’t interfere with the participants’ ability to taste sweetness. Researchers say that there is the possibility that GIV3727 may work better in some people than others as some testers were able to detect bitterness to some degree.

GIV3727 could also lead to important new insights in the scientific area according to the research team as bitter taste receptor antagonists hold promise as tools to explore the taste receptor signalling in other systems.

They said: “Recent evidence indicates that some bitter receptors are also expressed in other nongustatory tissues with proposed roles in the detection of noxious airborne chemicals or regulation of glucose homeostasis via the gastrointestinal tract.”