Sweet taste of dilute NaCl: Psychophysical evidence for a sweet stimulus

Dilute NaCl tastes sweet. This sweetness could result from coding confusions in the nervous system such that weak NaCl produces neural signals resembling those for sweeteners like sucrose. On the other hand, an analysis of the structural chemistry of water-salt interactions suggests that water shells organized around cations may actually provide a sweet stimulus indistinguishable (to the receptor molecules) from more conventional sweet stimuli. In the present experiment, the sweetness of weak NaCl was abolished in two ways: by adaptation to sucrose and by topical application of Gymnema sylvestre. Since these two operations also abolish the sweet taste of a variety of conventional sweetners, the sweet taste of NaCl appears to result from the presence of a sweet stimulus.