Effect of stimulus volume on taste detection threshold for NaCl

An ascending method of limits with a three stimulus forced choice response procedure was used to determine detection thresholds for NaCl at stimulus volumes of 0.05, 0.5 and 0.9 ml, with and without an intertrial 0.9-ml water rinse. Results suggested an inverse relationship between stimulus volume and taste threshold. The rinse condition produced a small non-significant improvement in detection for all volumes. Thresholds, varying from 1.8 to 5.6 mM, were similar to those determined by other investigators in which much larger stimulus volumes were used. These results demonstrate that a rapid, small volume, no-rinse method of the type commonly used in clinical practice to measure taste detection thresholds can be used to yield valid estimates of taste threshold.