title: Temperature Affects Human Sweet Taste via At Least Two Mechanisms.
abstract: The reported effects of temperature on sweet taste in humans have generally been small and inconsistent. Here, we describe 3 experiments that follow up a recent finding that cooling from 37 to 21 °C does not reduce the initial sweetness of sucrose but increases sweet taste adaptation. In experiment 1, subjects rated the sweetness of sucrose, glucose, and fructose solutions at 5-41 °C by dipping the tongue tip into the solutions after 0-, 3-, or 10-s pre-exposures to the same solutions or to H2O; experiment 2 compared the effects of temperature on the sweetness of 3 artificial sweeteners (sucralose, aspartame, and saccharin); and experiment 3 employed a flow-controlled gustometer to rule out the possibility the effects of temperature in the preceding experiments were unique to dipping the tongue into a still taste solution. The results (i) confirmed that mild cooling does not attenuate sweetness but can increase sweet taste adaptation; (ii) demonstrated that cooling to 5-12 °C can directly reduce sweetness intensity; and (iii) showed that both effects vary across stimuli. These findings have implications for the TRPM5 hypothesis of thermal effects on sweet taste and raise the possibility that temperature also affects an earlier step in the T1R2-T1R3 transduction cascade.
authors.affiliation: The John B. Pierce Laboratory, 290 Congress Avenue, New Haven, CT 06519, USA and The Department of Surgery (Otolaryngology), Yale School of Medicine, 333 Cedar Street, New Haven, CT 06510, USA green@jbpierce.org.
authors.forename: Barry G
authors.initials: BG
authors.lastname: Green
authors.affiliation: The John B. Pierce Laboratory, 290 Congress Avenue, New Haven, CT 06519, USA and.
authors.forename: Danielle
authors.initials: D
authors.lastname: Nachtigal
mesh_terms: D000293:Adolescent; D000328:Adult; D002241:Carbohydrates / Q000494:pharmacology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012996:Solutions / Q000737:chemistry; D013549:Sweetening Agents / Q000494:pharmacology*; D050053:TRPM Cation Channels / Q000378:metabolism; D013649:Taste / Q000187:drug effects* / Q000502:physiology; D013652:Taste Threshold / Q000187:drug effects; D013696:Temperature; D055815:Young Adult
chemical_list: D002241:Carbohydrates; D012996:Solutions; D013549:Sweetening Agents; D050053:TRPM Cation Channels; C404409:TRPM5 protein, human
keywords: TRPM5; human; psychophysics; sweetness; taste; temperature