Teixeria has already determined that the sweetness of thaumatin is related to the specific charges across a large surface area over which thaumatin can bind to the principle human taste receptor.

"We still have a long way to go to fully understand such a vital thing as taste, but neutrons will play an important role in research in this area, " she says.

The reason, new research suggests, may be that the brain cells in the area responsible for the secondary, or extra, sense—for instance, the chocolate taste—are overly active.