Putting out the fire: Effects of tastants on oral chemical irritation

Abstract

Intense oral irritation, lasting 10 min or more, was induced by rinses with I or 2 ppm capsaicin or with 100 ppm piperine. Subjects judged the perceived irritation after these treatments while periodically rinsing their mouths with solutions of one of four tastants (quinine, sucrose, NaC1, or citric acid), with water, or with nothing (a "no-tastant" condition). The decay of perceived irritation over time was linear for piperine and exponential for capsaicin. The decline in irritation was fastest during trials with citric acid and with sucrose (but more so for sucrose in the capsaicin trials), intermediate for NaC1 and water, and slowest for quinine and the no-tastant condition. Perceived irritation was generally lower while tastant solutions were held in the mouth (relative to irritation rated before sipping them or after expectoration), suggesting an inhibitory effect of oral cooling. © 1986 Psychonomic Society, Inc.