Sensory perception and pleasantness of food flavors in elderly subjects

This study was designed to determine the perceived intensity and pleasantness of different food flavors. A group of 32 young subjects (mean age: 22, range 20-25) and 23 elderly subjects (mean age: 76, range 72-82) judged the intensity and the pleasantness of five series of food flavors, each with five geometrically spaced concentration levels: (a) bouillon flavor in water, (b) tomato juice flavor in water, (c) orange juice flavor in water, (d) strawberry flavor in yogurt, and (e) sugar in unsweetened yogurt. On average, the elderly subjects had lower perceived intensities for the highest concentrations of the series of bouillon, tomato juice, strawberry flavor in yogurt, and sugar in yogurt, whereas the average responses to the lowest concentrations were almost equal. The slope of the psychophysical function for the orange juice flavor was equal for the group of young and elderly subjects. Optimal preferred concentrations were higher for the elderly than for the young subjects in the cases of bouillon, tomato juice and orange flavor. Optimal concentrations for strawberry flavor and sugar in yogurt were about equal. It was found that there are considerable differences between young and elderly subjects in the sensory perception and pleasantness of food flavors. Changes with age in functions relating (a) concentration with perceived intensity (psychophysical), (b) concentration with pleasantness, and (c) perceived intensity with pleasantness were specific for the different flavor qualities.