Raphaël Monod (Thesis began in 2021)

This PhD project is part of the ANR-funded project Sal&Mieux which purpose is to optimize the use of discretionary salt. To do so, one should first understand how the added salt behaves in the food matrix (Q1) and secondly how the salt released from the food matrix is perceived in the mouth and how the flavor perception is modulated in the course of this dynamical process (Q2). To address Q1, complementary physicochemical (atomic absorption spectroscopy, modelling) and imaging approaches (23Na Magnetic Resonance Imaging) will be developed and used to quantitatively evaluate the distribution of sodium for a variety of food matrices and their preparation process. Sodium MRI will be performed using high field MRI equipment to tackle the mechanisms underlying the effects of the target factors on both 3D spatial distribution and bounding of salt. The same approach will be applied to water to understand further salt release and perception mechanisms. To address Q2, the temporal release of sodium in the mouth during consumption of food products will be characterized using in vitro and in vivo recordings. Salt release will be monitored in vitro, using a dedicated mouth simulator, according to a variety of food matrices and their preparation process. Simultaneous in vivo recordings will encompass (i) dynamic sodium release and dynamics of pH in mouth using in-mouth sensors; (ii) salt-associated aroma compounds release to evaluate the contribution of aroma compounds to the overall salty flavor and (iii) temporal sensory perception using dedicated sensory methods.

This thesis is co-directed by Sylvie Clerjon (QuaPA, AgroResonance) and Thierry Thomas-Danguin (CSGA, Dijon).