Noncaloric sweeteners have enabled a reduction of carbohydrate
sweeteners in the diet for many years, thus combating obesity, diabetes,
and other health disorders. However, many consumers reject noncaloric
sweeteners, as they exhibit delays in sweetness onset, objectionable
lingering sweet aftertaste, and the absence of sugar-like mouthfeel.
We propose that the temporal taste differences between carbohydrate
and noncaloric sweeteners result from slowed diffusion of the latter
to and from sweetener receptors through the amphipathic mucous hydrogel
covering the tongue. Also,
we demonstrate that formulation of noncaloric sweeteners with K+/Mg2+/Ca2+ mineral salt blends markedly
attenuates lingering sweetness, an effect believed to be due to a
composite of osmotic and chelate-mediated compaction of the mucous
hydrogel covering the tongue. For example, sweetness linger values
(intensity units in % sucrose eq) for rebaudioside A and aspartame
are reduced from 5.0 (0.5 SD) to 1.6 (0.4 SD) and from 4.0 (0.7 SD)
to 1.2 (0.4 SD), respectively, by formulation with 10 mM KCl/3 mM
MgCl2/3 mM CaCl2. Finally, we propose that sugar-like
mouthfeel is a consequence of K+/Mg2+/Ca2+ activation of the calcium-sensing receptor present in a
subset of taste bud cells. For example, the mouthfeel intensity of
a sucrose solution increased from 1.8 (0.6 SD) to 5.1 (0.4 SD).