Taste sensitivity is measured by five taste solutions（salty、sour、bitter、sweet、umami). Every taste solution contains 8 different concentration. Detection , recognition and difference thresholds will be measured .Their definitions are as bellow.
Detection threshold：minimum value of sensory stimulus needed to give rise to a sensation. The sensation need not be identified.
Recognition threshold：minimum value of a sensory stimulus permitting identification of the sensation perceived.
Difference threshold：value of the smallest perceptible difference in the physical intensity of a stimulus.