Relation between PROP taster status and fat perception, touch, and olfaction

We tested the hypothesis that fat perception (sensitivity to and preference s for fat) may be linked to 6-n-propylthiouracil (PROP) taster status as a result of differences in trigeminal innervation of the oral cavity. In addi tion, we examined the relationship between taster status and sensitivity to other taste attributes, as well as tactile and olfactory sensitivities. Su bjects (40 nontasters, 67 medium tasters, and 40 supertasters of PROP) rate d samples (potato chips, chocolate drink, mashed potatoes, and vanilla pudd ing) varying in fat and flavor concentrations for the intensity of fattines s, saltiness, and sweetness, first without and then with nose clips, and fo r liking. Tactile sensitivity of the tongue was assessed according to respo nses to stimulation with Von Frey filaments (2.36, 2.44). Olfactory thresho lds were determined for two odors (diacetyl and phenylethyl methyl ethyl ca rbinol). In general, taster status was not related to the perceptions of fa t, saltiness, and sweetness. Subjects were able to accurately assess the fa t content of the samples. Increasing the flavor levels in the potato chips and mashed potatoes enhanced the perception of fattiness for these systems. Supertasters were more sensitive to stimulation on the median of the tongu e with the no. 2.36 Von Frey filament, and the olfactory thresholds for dia cetyl were lower for PROP tasters and supertasters than for nontasters. (C) 2001 Elsevier Science Inc. All rights reserved.