32-24 – Is taster status predictive of implicit liking of bitter, astringent and chemesthetic compounds

Food choice and food intake are guided by both multisensory and metabolic processes. Genetic taster status (GTS) is an inherited relative sensitivity to taste stimulation, assessed via density of the fungiform papillae and/or perceptual sensitivity to the bitter compound 6-n-Propylthiouracil (PROP). However, the effects of GTS on food preferences goes beyond just bitter gustatory tastants. For example, significant relationships have been reported between GTS and responses to somatosensory (trigeminal), chemesthetic and astringent stimuli. To capture these varied sensory experiences, hedonic responses to oral stimuli are typically measured using subjective rating scales. The aim of this study was to determine whether facial Electromyography (EMG), and Electrocardiography (ECG), established implicit measures of affect, can predict individual differences in dis/liking of bitter tasting, chemesthetic, and astringent compounds. Participants were pre-screened for GTS. Then, trial by trial, facial EMG and ECG responses to threshold and super-threshold concentrations of caffeine (bitter), menthol (chemesthetic) and alum (astringent) were measured. It was found that super-tasters perceived all three stimuli to be more intense than non-tasters, with EMG, but not HR, reliably differentiating between the two groups, specifically at supra-threshold concentrations.