Comparison of five common acceptance and preference methods

Acceptance and preference of the sensory properties of foods are among the most important criteria for determining food choice. Although consumer acceptance and preference testing are now widely applied, it is still a matter of opinion as to how best testing should be done, including what specific methodology should be used. The aim of this study was to compare three consumer acceptance methods (9-point hedonic, labeled affective magnitude and unstructured line scales) and two consumer preference methods (best–worst scaling and preference ranking) in terms of the results they generate and aspects of implementation. This study sought to better understand; how well individual methods discriminate samples, similarities and difference in their patterns of sample discrimination, consumer perception of their implementation, and practicalities. Consumers evaluated six samples in duplicate by acceptance ratings and preference ranking, and 10 triads for best–worst scaling. While all test methods detected a significant difference between samples (p < 0.05), a larger F-value or improved discrimination, was produced by best–worst scaling compared to acceptance methods. Significant pair-wise sample comparisons were also observed among the methods. Preference maps of individual test methods further illustrated similar sample preferences with regard to sensory properties of products. Comparison of discriminability across methods by generalized procrustes analysis (GPA) found that the patterns of sample discrimination were very similar. Based upon consumer perception, methods were equally easy to use and allowed for accurate information to be given. Regarding practicality, and number of samples that must be tasted, best–worst scaling was the most demanding, followed by preference ranking, and then the acceptance methods. Results indicated that under controlled laboratory testing conditions greater discrimination occurred by best–worst scaling. However, similar conclusions were reached when determining whether consumer acceptance or preference was obtained by the 9-point hedonic scale, labeled affective magnitude, unstructured line scale or preference ranking. Sample size, product type and type of data produced should be taken into account when selecting a test method.