Intensity/time relationships in sweetness: evidence for a queue hypothesis in taste chemoreception

Details of reaction time, total persistence time and time of protracted maximum intensity of sweetness in relation to concentration of sucrose and thaumatin are presented. Reaction time approaches a constant value at an early concentration for both sweeteners and maximum times for maximum intensity occur at lower concentrations than total maximum persistence. These observations seem best explained by a two-stage model of taste chemoreception, the first consisting of an orderly queue of stimulus molecules approaching the ionophor and the second being the depolarisation at the ionophor itself. The orderly queue model is capable of explaining all the temporal phenomena of sweet taste including the plateau of maximum time at maximum intensity which is observed at all concentrations. It also offers a novel view of the way in which intense sweeteners such as thaumatin may achieve their effects and broadens the scope for taste modifier research in the future.