MACARON

MACARON addresses a new and fundamental question: the role of the oral mucosa (OM) in flavour perception (Axe 1.5, LS09, keywords: flavour and sensoriality). It also considers for the first time the role of MUC1, a tethered mucin expressed at the surface of the oral epithelial cells, in the structure and properties of the mucosal pellicle (MP) and flavour perception, focusing on astringency and aroma perception. MACARON takes the comprehension and characterization of astringency perception to new levels by exploring the current and new hypotheses of its molecular basis and by integrating both cross-molecular and cross-modal interactions with the aroma perception. Indeed, we propose that MUC1, as a signalling protein, is involved in the molecular mechanisms underpinning the perception of astringency via structural modifications (i.e., cleavage of its two subunits), initiating an intracellular calcium signal that leads to the release of neurotransmitters. We also suggest that the composition of the MP determines its properties and thus its ability to interact with aroma compounds and that the MP aggregation by astringent compounds impacts MP-aroma compound interactions. MACARON also considers the cerebral integration of these two multimodalities of flavour to understand how aroma and astringency perceptions impact each other. These scientific questions are declined into 7 objectives that will be reach through a strategy based on the development of different experimental systems, including a model of the oral mucosa, protein models and a device for in vitro tribological experiments. This strategy results in a 4-year project divided into 4 main work packages (WPs), plus 1 WP dedicated to coordination and 1 WP dedicated to dissemination. This organization aims to compare in vitro and in vivo results to validate the model of the oral mucosa and to investigate flavour molecular mechanisms. MACARON is also a multidisciplinary project and its partnership combined expertise of (i) food chemistry and perception, biochemistry and analytical chemistry of proteins and aroma compounds from team 1 of the “Centre des Sciences du Goût et de l’Alimentation” (CSGA) (P1a); (ii) biochemistry, molecular biology and calcium imaging from the CSGA’s team 2 (P1b); (iii) cutting-edge microscopic techniques, including atomic force microscopy-based techniques, from the “Institute Carnot de Bourgogne” (P2) and (iv) tribology from the “Laboratoire de Tribology et de Dynamique des Systèmes” (P3) to explore hypotheses on the origin of astringency and solutions based on aroma to modulate its intensity. It is the first time that a project will merge these expertises to elucidate the molecular basis of astringency and will merge physic measurements of friction forces at the micro- and nanometric scales while considering for the first time the associated vibratory signal. Thus, MACARON will provide a breakthrough in the role of the oral mucosa in astringency and aroma persistence, which are two important modalities of flavour. The output of MACARON on the role of the MP in flavour perception, while considering multimodal integration of flavour, will enable new solutions for the development of food products to be proposed.