Alexy BRUNEL PhD defense

Multiscale analysis of thickened drinks for dysphagia management: from rheological and structural characterization to sensory perception
Multiscale analysis of thickened drinks for dysphagia management: from rheological and structural characterization to sensory perception

Organic Chemistry & Interfaces (COrInt) team

Abstract
This PhD project focuses on thickened drinks for dysphagia management. It aims to determine the influence of gel structure on their rheological properties and the sensory perception of texture, enabling the development of new products.
In practice, ten gels were studied, formulated from polysaccharides from different natural sources. These gels are at the threshold of level 4 of the IDDSI scale, which represents the thickest level for liquids. Using scanning electron microscopy and small-angle X-ray scattering, we unravelled their microscopic and nanoscale structure. To fully characterize the gelation mechanisms and their viscoelastic, sliding, flow, fracture, lubrication, and ageing properties, various rheological tests including shear, compression, and tribology were performed. These experiments included the nonlinear regime to approximate the conditions of food oral processing. These ten gels span a broad spectrum of rheological behaviours.
In parallel, a descriptive analysis was conducted using a trained panel. The ten gels represent a wide sensory range. Regardless of the formulation, correlations between rheological measurements and sensory evaluation were identified. These correlations demonstrate marked and nontrivial synergistic effects between the different ingredients. Additionally, ω3-doped gel drinks were formulated and characterized, paving the way for nutritional enrichment.

Jury

  • Claire Berton-Carabin, Research Director, INRAE, BIA, Nantes / Reporter
  • Deniz Gunes, Professor, SMaRT, KU Leuven, Louvain / Reporter
  • Amélie Banc, Associate Professor, L2C, Université de Montpellier, Montpellier / Examiner
  • Cassandre Leverrier, Associate Professor, SayFood, AgroParisTech, Paris / Examiner
  • Lazhar Benyahia, Professor, IMMM, Le Mans Université, Le Mans / Examiner
  • Arnaud Saint-Jalmes, Research Director, CNRS, IPR, Université de Rennes / PhD Supervisor
  • Ludovic Paquin, Associate Professor, ISCR, Université de Rennes / PhD Co-Supervisor

Invités

  • Fabienne Gauffre, Directrice de recherche, CNRS, ISCR, Université de Rennes

  • Véronique Vié, Associate Professor, IPR, Université de Rennes

Contacts