title: Different oral sensitivities to and sensations of short-, medium-, and long-chain fatty acids in humans.
abstract: Fatty acids that vary in chain length and degree of unsaturation have different effects on metabolism and human health. As evidence for a "taste" of nonesterified fatty acids (NEFA) accumulates, it may be hypothesized that fatty acid structures will also influence oral sensations. The present study examined oral sensitivity to caproic (C6), lauric (C12), and oleic (C18:1) acids over repeated visits. Analyses were also conducted on textural properties of NEFA emulsions and blank solutions. Oral thresholds for caproic acid were lower compared with oleic acid. Lauric acid thresholds were intermediate but not significantly different from either, likely due to lingering irritating sensations that prevented accurate discrimination. From particle size analysis, larger droplets were observed in blank solutions when mineral oil was used, leading to instability of the emulsion, which was not observed when emulsions contained NEFA or when mineral oil was removed from the blank. Rheological data showed no differences in viscosity among samples except for a slightly higher viscosity with oleic acid concentrations above 58 mM. Thus, texture was unlikely to be the property used to distinguish between the samples. Differences in oral detection and sensation of caproic, lauric, and oleic acids may be due to different properties of the fatty acid alkyl chains.
authors.affiliation: Department of Food Science, Purdue University, West Lafayette, Indiana; and.
authors.forename: Cordelia A
authors.initials: CA
authors.lastname: Running
authors.affiliation: Department of Nutrition Science, Purdue University, West Lafayette, Indiana mattes@purdue.edu.
authors.forename: Richard D
authors.initials: RD
authors.lastname: Mattes
mesh_terms: D000284:Administration, Oral; D000328:Adult; D002208:Caproates / Q000008:administration & dosage; D018592:Cross-Over Studies; D004655:Emulsions; D005227:Fatty Acids / Q000008:administration & dosage* / Q000737:chemistry; D005260:Female; D006801:Humans; D007850:Lauric Acids / Q000008:administration & dosage; D008297:Male; D008899:Mineral Oil / Q000008:administration & dosage; D015394:Molecular Structure; D009055:Mouth / Q000294:innervation*; D019301:Oleic Acid / Q000008:administration & dosage; D010316:Particle Size; D012212:Rheology; D013329:Structure-Activity Relationship; D013652:Taste Threshold; D014783:Viscosity; D055815:Young Adult
chemical_list: D002208:Caproates; D004655:Emulsions; D005227:Fatty Acids; D007850:Lauric Acids; C030358:lauric acid; C037652:hexanoic acid; D019301:Oleic Acid; D008899:Mineral Oil
keywords: fat taste; fatty acid chain length; fatty acid irritation; nonesterified fatty acid taste