Development of a sensory tool to assess overall liking for the fatty, salty and sweet sensations
Résumé
Understanding the origin of the overconsumption of too high levels of sucrose, sodium chloride and lipids
in foods raises the question of the influence of the hedonics for these sensations. To better understand
this relationship, a sensory tool that enables measurement of liking towards sweet, salty or fatty sensations
is required. This liking towards a sensation has to be understood as an overall attractiveness of the
sensation. Instruments already existing were unsatisfactory as including a limited number of foods not
representative of the overall sensation.
A set of hedonic tests, named PrefSens, was developed to measure an overall liking for fatty, salty or
sweet sensations. Each test consisted in the rating on a 9-point hedonic scale of a food product at 5 different
levels of lipids, sodium chloride or sucrose. To build the PrefSens test, a total of 144 food ranges
were tested during the development step (n = 341 subjects) including various food categories, matrices
and serving temperatures. Then, based on the technical feasibility and ability to discriminate, 32 food
ranges were selected (10 for fatty, 10 for salty and 12 for sweet). The perceived intensity of fatty, salty
or sweet ‘‘sensations” of these selected foods was evaluated by a trained panel (n = 12) using
Spectrum scales. During the application study, the hedonic evaluation of the selected foods was assessed
in 6 tasting sessions by 567 subjects over 8 laboratories spread out in France. For each subject and each
product, hedonic ratings (y) were fitted versus the level of fatty, sweet or salty (x) in a quadratic regression,
from which the predicted optimal level (Lpref) was derived based on the x-coordinate of the parabola’s
maximum weighted by the correlation coefficient between observed and predicted data. The
overall liking score for fatty, salty or sweet sensations was the average Lpref over the compounding food
ranges.
The sensory profile showed that within each sensation the mean perceived intensity significantly
increased in a linear manner with the nutrient level. An exception was for the two lowest levels of lipids
which were not significantly perceived differently. Concomitantly, the overall liking scores followed an
inverted U-shape centered on the middle level of lipids, sodium chloride or sucrose. The distribution
was close to normality. Internal validity and consistency of the items compounding the sensations of
fatty, salty or sweet were demonstrated. PrefSens is an internally valid and original tool that can be
applied to a population sample in order to better understand the determinants of dietary behaviors.