Development of an olfactory test method for measuring perception of everyday food odors among older adults

Age related decline in olfactory function has major implications for food intake in older adults as the sense of smell is essential to the perception of food. The aim of this study was to develop an olfactory test method that addresses the consequences of decline in intensity perception in relation to food appreciation. This test was developed in four steps: (a) Selection of diverse food odors, evaluated on perceived familiarity. (b) Standardization of an intensity reference level for food odors in relation to 1-butanol. (c) Assessment of shelf-life stability. (d) Test–retest reliability for intensity and identification. Fourteen food odors comprising asparagus, bacon, banana, cinnamon, curry, coffee, fried meat, mushroom, onion, orange, raspberry, thyme, toasted bread, and vanilla obtained satisfactory familiarity score, test–retest reliability, and a stable shelf-life except for cooked fish which was therefore excluded. This food odor test is a promising tool for evaluating olfactory performance in older people in relation to common foods and changes in preferences. However, more work is needed to further evaluate the method in practice in a larger cohort including older adults and a reference group. Practical Applications: This food odor test using complex food odors is relevant in settings where meals are customized to improve food intake in older adults.