How flavour and appearance affect human feeding

Abstract

The amount of food eaten during a meal is determined by both internal physiological events and factors in the environment such as the availability, cost and presentation of food as well as the time of day and the social situation (Pliner, 1978; Rodin, 1980). It is the purpose of this paper to consider the ways in which the different sensory aspects of food presentation such as flavour, appearance, portion size and shape influence food intake in human subjects within the range of normal bodyweights. One way in which the sensory properties of food influence feeding is by contributing to a form of satiety which is partly specific for the particular food eaten. Sensory specijic satiety Cabanac (1971) has suggested that the palatability or subjective pleasantness of a particular food depends on its usefulness as determined by internal bodily signals. He found that sweet solutions of sucrose and a food-related smell (orange) were rated as pleasant when subjects were hungry, but after they had been given a load of glucose or sucrose either orally or directly into the stomach, the previously pleasant taste or smell became less pleasant. We wished to know whether such changes in palatability were relevant to normal feeding and could be found with real foods after they had been consumed. Thus we determined the effect of eating one food to satiety on the subjective pleasantness of that food and of other foods which had not been eaten (Rolls, Rolls et al. 1981). Twenty-four subjects rated the taste of eight foods (cheese on cracker, sausage, chicken, walnuts, bread, raisins, banana, cookies) on a scale where + 2 was very strong liking and-2 was very strong dislike. After this initial rating, subjects were given a plate of either cheese on crackers or sausages and instructed to eat as much as they liked. Two minutes after the end of the meal subjects rerated the tastes of the eight foods. It was found (see Fig. I) that the liking for the food eaten went down significantly more than for the foods not eaten (P