Construction of an individualized sensory space of tastes in water using skin blood flow responses

Abstract

Perception of tastes and odors in water is a major interest for water producers and distributors because off-flavors in tap water are associated with health risk by consumers. However, the taste of water is difficult to describe due to the medium itself which is supposed to have no taste. Classical sensory methodologies are difficult to adapt and only get part of the whole perception. This study suggests a new approach to qualify and quantify taste of water using multiple physiological measurements to go back up the perception chain. The four basic tastes (sweet, salty, acid and bitter) were used and diluted in Evian water as a standard, at low concentrations. Autonomic system responses were measured with skin blood flow variations. Results from skin blood flow variations are presented and indicate a high correlation between the duration and amplitude of the response with the self-reported intensity and pleasantness of the stimulus. It also shows that physiological measurements enable the significant discrimination of the different tastes even at detection threshold concentrations. The prediction of the characteristics of a stimulus might be obtained by combining multiple physiological data and sensory responses.