title: Caffeine as a flavor additive in soft-drinks.
abstract: Over 60% of soft-drinks sold in the United States contain caffeine, a mildly addictive psycho-active chemical, as a flavor additive. Using sweeteners as controls, we assessed whether caffeine has flavor activity in a cola soft-drink. A forced-choice triangle discrimination methodology was used to determine detection thresholds of caffeine in sweeteners and a cola beverage. The subjects (n=30, 28 female, 23+/-4 years old) were trained tasters and completed over 1600 discrimination tests during the study. The mean detection thresholds for caffeine in the sweet solutions were: 0.333+/-0.1mM sucrose; 0.467+/-0.29 mM aspartame; 0.462+/-0.3mM sucralose, well below the concentration in common cola beverages (0.55-0.67 mM). A fixed concentration of caffeine, corresponding to the concentration of caffeine in a common cola beverage (0.67 mM) was added to the sweeteners and a non-caffeinated cola beverage. Subjects could distinguish between caffeinated and non-caffeinated sweeteners (p<0.001), but all subjects failed to distinguish between caffeinated and non-caffeinated cola beverage (p=1.0). Caffeine has no flavor activity in soft-drinks yet will induce a physiologic and psychologic desire to consume the drink.
authors.affiliation: School of Exercise and Nutrition Sciences, Deakin University, 221 Burwood Highway, Burwood, Victoria 3125, Australia. russell.keast@deakin.edu.au
authors.forename: Russell S J
authors.initials: RS
authors.lastname: Keast
authors.forename: Lynnette J
authors.initials: LJ
authors.lastname: Riddell
mesh_terms: D000328:Adult; D001066:Appetite / Q000187:drug effects*; D001218:Aspartame / Q000008:administration & dosage; D002110:Caffeine / Q000008:administration & dosage*; D002253:Carbonated Beverages / Q000032:analysis*; D019422:Dietary Sucrose / Q000008:administration & dosage; D005260:Female; D005421:Flavoring Agents / Q000008:administration & dosage*; D006801:Humans; D008297:Male; D013395:Sucrose / Q000008:administration & dosage / Q000031:analogs & derivatives; D013549:Sweetening Agents / Q000008:administration & dosage; D013649:Taste / Q000502:physiology*
chemical_list: D019422:Dietary Sucrose; D005421:Flavoring Agents; D013549:Sweetening Agents; D002110:Caffeine; D013395:Sucrose; C026285:trichlorosucrose; D001218:Aspartame