Psychology of perception: sensory evaluation and context. Theory and applications

Association between nutritional values of hays fed to horses and sensory properties as perceived by human sight, touch and smell

International audience; Although hay is the foundation of most equine diets, horse owners rarely ask for biochemical analysis and the routine practice is to choose hay based on its 'perceived' nutritional value. The present study aimed at exploring the relationship between sensory properties as perceived by sight, touch and smell, and the nutritional value of hay measured by biochemical analysis using a 'free sorting task' method. Fifty-four non-expert participants were asked individually to: (1) observe 21 hays samples, (2) group together hays that they perceived as similar for each of the three modalities (hay appearance, odour or texture) and (3) characterize each formed group with a max…

Crispness: a critical review on sensory and material science approaches

International audience; Many texture studies have been published on crispness because of the great interest of consumers towards crispy foods. This work reviews the existing literature on the topic, and especially the different approaches, instrumental and sensory, applied to study crispness. These studies result in a wide range of data but, because crispness is not a clearly defined sensory attribute, the conclusions that can be drawn from these studies should be carefully examined. The physical basis for crispness are discussed and the role of structure, hydration and ingredients on crispness and its stability are presented.

Effect of Water on the Mechanical Behaviour of Extruded Flat Bread

Abstract The effect of water on the mechanical properties of extruded breads was studied, at room temperature. As the moisture content was increased from 6 to 9% moisture, the resistance to fracture (compression tests) or rupture (tensile tests) was improved. Above this moisture range, plasticisation by water was the dominant phenomenon. The brittle to ductile transition was observed to occur within a moisture content range from 9 to 13·7% (w/w). The influence of water on the crispness of extruded bread, evaluated with sensory evaluation, is also described.

SPECTRAL COMPOSITION OF EATING SOUNDS GENERATED BY CRISPY, CRUNCHY AND CRACKLY FOODS

Separate air and bone conducted food sounds generated by six subjects biting into eight foods were recorded and analysed by a fast Fourier transform (FFT) signal analyser. A panel of 60 subjects classified the 8 foods according to their texture: crispy, crunchy and crackly and these textural characteristics were described by spectral characteristics of biting sounds. Crispy foods (such as extruded flat breads) were found to generate high pitched sounds that show a high level of frequencies higher than 5 kHz, especially for air conduction. Crunchy foods (such as raw carrot) generate low pitched sounds with a characteristic peak on frequency range 1.25 to 2 kHz for air conduction. And crackly…

Impact of fabric end-use knowledge on handle perception

Abstract The objective was to determine whether the knowledge of the fabrics' end-use may impact the way textile experts organize their haptic perception. Two groups of 10 textile experts were asked to freely sort the same set of 25 fabrics in two different contexts. The first group was informed that the set of fabrics would be used to make dresses and the other one that they would be used to make sportswear. Both groups also rated the appropriateness of each fabrics for each end-use. Results did not show any effect of the end-use context. The two perceptual spaces were basically the same and accounted for appropriateness of use similarly. If confirmed, this result indicates that descriptiv…

REPLICATED TRIANGLE TESTS: EFFECT OF FEED-BACK AND PRODUCT COMPARISON ON PERFORMANCE

The feed-back procedure consists of informing assessors of the quality of their response (correct or incorrect) after each triangle test. This procedure showed a contrasted effect according to assessors' detection abilities. A decrease in performance was observed for assessors who had low detection abilities whereas a slight increase was observed for assessors who had higher detection abilities. When the feed-back procedure is followed by a comparison by tasting of the two products, the increase in performance from the beginning to the end of the session is larger than that of both feed-back and control (no information) groups. We suggest that information inference from previous tests, whic…

EFFECT OF ASSESSORS EXPERTISE LEVEL ON EFFICIENCY OF WARM-UP FOR TRIANGLE TESTS

The effect of warm-up on performance for repeated triangle tests is studied according to assessors' expertise level for both triangle test strategy and the pair of products to compare. Three experiments performed with orange flavored soft drinks show that the effect of warm-up depends on the assessors' expertise: (1) naive assessors do not increase their performance with warm-up; (2) assessors with a moderate practice of both triangle tests and the pair of products improve their performance with warm-up; (3) assessors with a moderate practice of triangle tests, but not familiar with the pair of products, improve their performance with warm-up too; and (4) assessors highly experienced for bo…