Des qualités organoleptiques des aliments aux choix alimentaires

The sensory characteristics of foods are one critical factor of their palatability. The flavor of a food is determined by the perception of a complex set of sensory properties. Its palatability, the disposition to accept or reject the food, depends not only on sensory responses but also on previous experience of ingestion. A few acceptance or rejection responses are innate and are probably acquired during fœtal life. An individual hierarchy of preferences and aversions is acquired following the experience of ingestion of various foods, on the basis of a Pavlovian learning mechanism. Conditioned taste aversions are acquired for foods whose ingestion is followed by digestive malaise. Conversely, the postingestive experience of satiety determines the acquisition of food likes. Energy-dense foods, which induce strong satiety are usually very palatable for most people. Specific appetites also exist that correspond to the association between a particular food flavor and the satisfaction of specific nutrient needs. The notion of sensory specific satiety underlines the fact that satiety develops for the sensory characteristics of ingested foods, but much less, or not at all for foods with different sensory attributes, thereby facilitating the intake of a varied diet. This concept, whose brain mechanisms are being identified, stresses the importance of sensory factors in the control of food intake, in conjunction with internal, physiological factors.