PRA SEL « Réduction de la teneur en sel des aliments : une étude intégrée de la libération et de la perception du sel dans des aliments modèles et réels »

An excessive sodium intake may be a cause of pathology and the main sodium source is the sodium chloride (salt) added during the food processes or the preparation of meal. Nowadays, health authorities recommend decreasing progressively salt content in food products. Considered as a flavour enhancer, salt not only acts on salty perception but also on the flavour perception. Indeed, the final perception results from the integration of all the sensory information perceived during eating. Consequently, a decrease in salt content may reducethe global acceptance of a food, particularly in increasing blandness that could result in a decrease of interest and a negative economical impact. So, the reduction of salt content without any decrease of acceptability is the main challenge. This aim can be reached either by an increase of released salt in mouth during chewing food or by an enhancement of salty perception produced by perceptual interact ion with another modality. This implies to control the physical and rheological parameters of the food matrix and/or to have a good knowledge in salty related psychophysics. We work on three complementary approaches to reach these goals: 1. physical and modelling approaches to better understand the transfer phenomena of the aqueous solutes (salts, water, lactate, flavour compounds, etc) in a model lipoproteic matrix. This can help to better control the distribution of Na + and Cl - electrolytes; 2. physico-chemical and psychophysical approaches a llowing (i) to better understand how olfactory and gustatory stimuli are released during the mastication process of a solid food matrix in mouth, and to describe taste and flavour compound release during this process (ii) to investigate theolfaction/taste interactions in studying how one or a mixture of aroma compounds may enhance thesalty perception; 3. investigation on real food matrices to validate observations made on model matrices. All these studies are performed in intimate collaborations be tween the research teams. By examining thefactors implied in electrolytes diffusion in food matrices of different structures, the integration of saltytaste with aroma perception, physiological factors such as salivary and masticatory parameters, temporal flavour release, should give some means to formulate healthy low salt foods.