Discriminability and appropriateness of category scaling versus ranking methods to study sensory preferences in elderly

Two methods: the nine-point hedonic scale and hedonic ranking, have been compared for their discrimination power and appropriateness when studying hedonic responses in elderly. A group of 35 elderly subjects (aged 60-88) and a control group of 35 young adults (aged 20-25) participated in the comparison. Five samples of each of two commercial fruit juices (apple and orange) differing in sensory profiles served as test material. Generally hedonic discriminability in elderly was lower than in young subjects for both methods. Ranking appeared to be more discriminating for apple juice samples, where hedonic differences among samples were smaller (F sample(apple), = 8.80); for orange juice samples, of more pronounced hedonic differences (F sample(orange) = 17.24) both methods revealed equal discriminability. From simplicity of the task and "user friendliness" of the tasting procedure, hedonic ranking seems to have some advantages over nine-point hedonic scaling. Results obtained by both methods for both juices were significantly correlated for elderly as well as for young subjects. However, the strength of correlation (Spearman R value) in elderly was much lower (R-apple=0.2217; R-orange=0.2213) than in young (R-apple=0.4766; R-orange=0.4844). Repeatability of hedonic assessment of orange juice samples performed by elderly (n = 27) 2 weeks after first evaluation for both methods was very good and did not show any advantage of one method over another. (C) 2003 Published by Elsevier Ltd.