FAT PERCEPTION IS RELATED TO PROP TASTER STATUS

Individuals who are sensitive to the bitter compounds phenylthiocarbam ide (PTC) and 6-n-propylthiouracil (PROP) are also more sensitive to s elected bitter and sweet substances, to sharp-tasting foods, and to th e trigeminal irritant capsaicin. PTC/PROP tasters have a greater densi ty of fungiform taste papillae and it is speculated that PTC/PROP tast ers also have more trigeminal innervation. Because oral texture percep tion is also mediated, in part, by trigeminal fibers, it has been prop osed that individual differences in fat perception might also be linke d to PTC/PROP taster status and taste bud density. This work tests the hypothesis that individuals who are PROP tasters: 1. have a higher de nsity of fungiform papillae; 2, are more sensitive to capsaicin; and 3 . have increased ability to discriminate differences in fat content in salad dressing. Individual subjects were classified as PROP nontaster s, medium tasters, or supertasters (n = 25 per group) by comparing the ir psychophysical function for PROP to that of NaCl. Papillae densitie s (papillae/cm(2)) were significantly different among the 3 taster gro ups (p less than or equal to 0.0001), and were highest among the super tasters. Both medium tasters and supertasters perceived more oral burn from capsaicin than did nontasters at concentrations of 50, 70, and 1 00 ppm (p less than or equal to 0.0001). Medium tasters and supertaste rs could also discriminate differences in fat content between 40% fat and 10% fat salad dressings (p less than or equal to 0.005),but the no ntasters could not. These data provide the first published evidence th at fat perception can be linked to genetic and anatomical differences between individuals. (C) 1997 Elsevier Science Inc.