Three breakfast cereals (two commercial products and one experimental product made by extrusion cooking) were placed over 10 saturated salt solutions in desiccators for 3 weeks and then studied by sensory and mechanical analysis. A slight decrease of sensory crispness intensity occurs between 0 and 0.50 (aw) or 7% (water content), after which there is a very rapid decrease. The value of critical water activity given by the intersection between the two straight lines which can be adjusted seems not to depend on the product. Moreover this value is confirmed by the mechanical analysis and, partially, by a Differential Scanning Calorimetry analysis. There is a good correlation between sensory crispness and deformation to the first fracture.

The noises perceived during sensory evaluation of foods are transmitted to the innerear by both air and bone conduction. The contribution of the two conductions was studied for six foods “croquant” (crunchy), “craquant” (crackle) and “croustillant” (crispy), by six panelists. It was studied by reconstituting the attenuation of the air and bone conduction records needed to imitate sound actually heard during sensory evaluation of foods. The eating technique (bite or chew) modified the contribution of air‐ and bone‐conduction to auditory sensation. Differences were shown between foods, but they could not clearly distinguish between the kinds of food. Modifying the attenuation of the air‐ and bone‐conduction records was not enough. The bone‐conduction records had to be attenuated over a frequency range around 160 Hz, which is the resonance frequency of the mandible. The air‐conduction records had to be attenuated at a frequency range around 160 Hz and amplified at a frequency range around 3,500 Hz in order to match the action of the middle‐ear muscles which behave differently when sounds were generated inside or outside the mouth.

The effect of process and formulation on sensory perception and flavor release was investigated on salad dressing models. Oil/vinegar emulsions (phi = 0.5, droplet size > 10 microm) with thickeners and a whey protein concentrate were prepared with different fat droplet sizes and different distributions of fat droplet size. The effect of the amount of emulsifier was also tested. Sensory profile analysis was performed by a trained panel and flavor release quantified by dynamic headspace analysis. When the droplet size is increased, the lemon smell and citrus aroma significantly increase, whereas the egg note, mustard, and butter aroma significantly decrease. The concentrations of alcohols and acids significantly increase when droplet size increases, whereas those of other compounds such as limonene or benzaldehyde significantly decrease. The dispersion of the droplet size has a small effect on flavor perception, and the effect of the increase of the amount of emulsifier is noticed only by instrumental analysis.

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Thirty Burgundy Pinot noir wines were evaluated by quantitative descriptive profile by nose (BN) and by mouth (BM) separately, by a trained panel composed of 12 judges. A specific vocabulary of 20 terms was developed. Sensory results were analyzed and compared by univariate and multivariate statistical techniques. Principal component analyses of the mean ratings BN and BM were fairly comparable regarding correlation among variables and the position of the wines. However, five sensory characteristics seem to be more intensely perceived BM, against 6 BN. Panel discrimination of the wines and panel repeatability in the measure were found to be slightly better BN than BM. A further canonical discriminant analysis on the data confirmed that panelists could well differentiate groups of wines from the same winemaker, probably corresponding to different style of winemaking.