21/10/2024: Elena KEULEYAN's thesis defence

Abstracts:

Animal proteins used as food emulsifiers are increasingly being replaced by plant-based protein ingredients derived from pulses. This shift is part of a broader redesign of our food systems, with an increase towards plant-based diets, the need for developing nutritionally balanced foods, and crucial sustainability challenges. However, these ingredients are extracted from seeds by moderate to intensive processing, which generates a structural and compositional complexity that is not yet fully understood. This also holds for the functional implications of their use to stabilize food emulsions by adsorbing at the oil-water interface. This research deploys an integrated approach from commercial ingredients, all the way to the digestive fate of the emulsions. Pea and lupin protein isolates and concentrates were selected. Endogenous phospholipids were found in the powders, which is a pivotal result in the field of protein ingredients. The competition for the interface between phospholipids and proteins was demonstrated at model interfaces and was confirmed in emulsions. It pointed to the decisive role of phospholipids on the physical stability of the emulsions and on their in vitro digestion. Indeed, the formulation route of these emulsions can be tuned to modulate this competition, which in turn was shown to modulate the in vitro digestibility and bioaccessibility of the dispersed lipids. This work paves the way for a better understanding of complex and sustainable ingredients, enabling to rationally formulate nutritious foods for tomorrow.

Composition du jury :

Rapporteurs before defence :

• Frédéric Carrière, Research Director, CNRS, UMR BIP
• Romain KAPEL, University Professor, CNRS, UMR LRGP

Examiners :

• Pierre Aymard, Thematic Director, Soredab, Savencia Group
• Véroinique Bosc, Senior Lecturer, AgroParisTech, UMR SayFood
• Agnès Montillet, University Professor, University of Nantes

Supervisor: Claire Berton-Carabin, Research Director, INRAE UR BIA

Thesis co-supervision: Anne Meynier, Research Officer, INRAE UR BIA & Alain Riaublanc, Research Officer, INRAE UR BIA