Temperature dependence of human taste responses

Human taste thresholds for NaCl, HCl, Dulcin and QSO₄ were determined at 17, 22, 27, 32, 37, and 42°C using the psychophysical method of forced choice. The thresholds for all four compounds were lowest between 22° and 32° and rose above and below this temperature range. The results favored a physical-chemical basis for the transduction process over an enzymatic explanation. The effect of temperature on the intensity of suprathreshold solutions of QHCl was tested by varying the adapting and stimulus temperatures of solutions presented to one side of the tongue in a matching procedure with a standard on the other side. The temperature effect was found to be independent of the adapting temperature and the standard concentration, and to depend only on the stimulus temperature.