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The sorting task is popular with sensory scientists because it provides rapid sensory profiles, even when product sets are complex or fatiguing. However, these sensory profiles generally cannot identify which sensory properties are driving subjects' perception of product similarities or differences—a critical task for the sensory analyst. This paper presents DISTATIS with Barycentric Text Projection as a solution that combines sorting-task and free-text data into a single-pass analysis to generate rapid, descriptive sensory profiles. This method is illustrated with a dataset generated by 25 subjects performing a replicated sorting and free-text description task in standard sensory-laboratory conditions on a set of 12 amari—bitter, herbal liqueurs that have not been previously analyzed in the sensory-science literature. DISTATIS with Barycentric Text Projection of the amari set produced sensory product maps that were readily interpretable. Using this analysis, the amari were grouped and described in ways that correspond to the available, popular literature descriptions of these products. The results of Barycentric Text Projection were compared to an independent Correspondence Analysis (CA) of the free-text data, and results were highly similar ( R V = 0.93 ). Future extensions of the method—such as analysis of descriptors in a check-all-that-apply (CATA) approach—are discussed. Overall, the successful, rapid, descriptive profiling of a set of 12 complex products using an untrained panel supports the potential of DISTATIS with Barycentric Text Projection as a sensory-evaluation tool.

A two-stage sorting task was used to probe Californian consumers’ opinions of twenty-five extra virgin olive oils based on visual assessments of the bottles. The modification of the simple sorting task aimed to encourage consumers to further discriminate products through sub-groupings of products within the groups they had already made. Sorting data were analyzed using a 3-way extension of classical multidimensional scaling called DISTATIS which explores the level of consumer agreement as well as the structure of the extra virgin olive oil products. Consumer agreements were explained by 46% of the variances found in the ways consumers sorted the bottles. Decreased amount of explained variance from the first stage to the second stage of the sorting task was observed in the olive oil product structures. Consumers were asked to describe the characteristics defining each group formed. Consumer comments were analyzed qualitatively prior to statistical analysis and were later used to understand the sorting results. Despite background differences in the usage of olive oil products, the majority of the consumers perceived the product set similarly. The two-stage sorting task allowed subjects to provide more criteria or multidimensional views of their perception of the products.

In the sensory evaluation literature, it has been suggested that sorting tasks followed by a description of the groups of products can be used by consumers to describe products, but a closer look at this literature suggests that this claim needs to be evaluated. In this paper, we proposed to examine the validity of the sorting task to describe products by trained and untrained assessors. The experiment reported here consisted in two parts. In a first part, participants sorted nine commercial beers and then described each group with their own words or with a list of terms. In a second part, participants were asked to match each beer with one of their own sets of descriptors. The matching task was used to evaluate the validity of the sorting task to describe products. Results showed that (1) the categories of trained and untrained assessors were comparable, (2) trained and untrained assessors did not describe groups of beers similarly, (3) for both groups, the results of matching task were not very good and presented a high inter-variability, and (4) providing a list of terms did not seem to help the assessors. Overall, the results suggest that the sorting task followed by a description does not seem to be adapted for a precise and reliable description of complex products such as beers but may be an interesting tool to probe assessors’ perception.

In this paper we present a new method called distatis that can be applied to the analysis of sorting data. D istatis is a generalization of classical multidimensional scaling which allows one to analyze 3-ways distance tables. When used for analyzing sorting tasks, distatis takes into account individual sorting data. Specifically, when distatis is used to analyze the results of an experiment in which several assessors sort a set of products, we obtain two types of maps: One for the assessors and one for the products. In these maps, the proximity between two points reflects their similarity, and therefore these maps can be read using the same rules as standard metric multidimensional scaling methods or principal component analysis. Technically, distatis starts by transforming the individual sorting data into cross-product matrices as in classical mds and evaluating the similarity between these matrices (using Escoufier’s R V coefficient). Then it computes a compromise matrix which is the best aggregate (in the least square sense, as statis does) of the individual cross-product matrices and analyzes it with pca . The individual matrices are then projected onto the compromise space. In this paper, we present a short tutorial, and we illustrate how to use distatis with a sorting task in which ten assessors evaluated eight beers. We also provide some insights into how distatis evaluates the similarity between assessors.

Previous work showed that trained assessors are better at discriminating and describing familiar chemico-sensorial stimuli than novices. In this study, we evaluated whether this superiority holds true for new stimuli. We first trained a group of subjects to characterize beer flavors over a two year period. After training was accomplished, we compared the performance of these trained assessors with the performance of novice subjects for discrimination and matching tasks. The tasks were performed using both well-learned and new beers. Trained assessors outperformed novices in the discrimination task for learned beers but not for new beers. But on the matching task, trained assessors outperformed novices for both learned and new beers. These results suggest that perceptual learning is harder to generalize than verbal learning.

Two questions are addressed in this paper: What can cognitive psychology bring to sensory evaluation? And what can cognitive psychology learn from sensory evaluation? In the first part, I will argue that one important contribution from psychology to sensory evaluation is to interpret flavor as a cognitively unified system made of three anatomically separated systems (smell, taste, and the trigeminal system). In the second part, I will argue that the applied field of sensory evaluation stresses the importance of using ecologically valid, naturalistic stimuli. Sensory evaluation also provides results that challenge accepted interpretations in psychology, especially in the field of evaluation of expertise.