The correlation of taste and chemesthetic sensation in individuals with different suprathreshold sensitivities

Abstract

Sensory tests involving taste-sensitive individuals provide the food industry with valuable information. However, the traditional evaluation of 6-n-propylthiouracil (PROP) tasters, which is assumed to reflect general taste sensitivity, is controversial. Therefore, the present study aimed to develop a rapid method for the classification of an individual's sensitivity to chemesthetic sensation, and to investigate the relationship between taste and chemesthetic sensation sensitivity at the suprathreshold level. In all, 72 young adults were screened and participated in the tests. The intensity of the pungency, heat, bitterness and saltiness that were presented via five concentrations of Sichuan pepper oleoresin (Spo), capsaicin, PROP and NaCl, respectively, were rated using generalized Labeled Magnitude Scales (gLMS). The method, namely 20% relative standard deviation (RSD), was developed for the classification of an individual's sensitivity. The results of ordinal multinomial logistic regression showed that the sensitivity to bitterness could be partly predicted by the sensitivity to saltiness, as well as the heat and pungency sensations. Furthermore, it was found that threshold should be used in conjunction with suprathreshold intensity ratings for classifying individuals. These findings regarding panelist sensitivity will be most useful in sensory evaluations of pungent food and in large-scale consumer studies.