Chem. Senses doi:10.1093/chemse/bjr126 Preference for Sucralose Predicts Behavioral Responses to Sweet and Bittersweet Tastants

Rats can be classified as either sucralose avoiders (SA) or sucralose preferrers (SP) based on their behavioral responses in 2-bottle preference, 1-bottle intake, and brief-access licking tests. The present study demonstrates that this robust phenotypic variation in the preference for sucralose predicts acceptance of saccharin, an artificial sweetener with a purported concentration-dependent ‘‘bitter’ ’ side taste and a 0.25 M sucrose solution adulterated with increasing concentrations of quinine hydrochloride (QHCl). Specifically, SA displayed decreased preference for and intakes of saccharin (‡41.5 mM) and sucrose–QHCl (>0.5 mM QHCl) solutions, relative to SP. In a second experiment involving brief-access (30-s) tests, SP and SA did not differ in their unconditioned licking responses across a range of sodium chloride or QHCl solutions (0.03–1 mM). However, the acceptability threshold for sucrose was lower in SA, relative to SP (0.06 and 0.13 M, respectively). Our findings suggest that phenotypic differences in sucralose preference are indicative of a more general difference in the hedonic processing of stimuli containing ‘‘bittersweet’ ’ or ‘‘sweet’ ’ taste qualities. Key words: artificial sweetener, individual differences, rats, tast