RESUMO
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).