Rheology and tribology: Two distinctive regimes of food texture sensation

Oral processing of food is a dynamic process involving a range of deformation processes. The mechanical properties and the rheology of food have been widely used to understand and predict in mouth flow properties and to discover relationships with sensory perception. However, only limited success has been realised using such approaches to characterise and to interpret food texture. Tribology is emerging as a contributing discipline for understanding oral processing of food as well as texture and mouthfeel, since it encompasses both the fluid’s (lubricant’s) rheological properties as well as the surface properties of the interacting substrates in relative motion.

► Two very different physical principles for the oral perception of food texture.
► “Oral” rheology dominates texture sensation at the early stage of eating.
► “Oral” tribology dominates texture sensation at the later stage of eating.
► Transition of food rheology to tribology reflected in TDS profile analysis.
► Texture features could be grouped as related to rheology or tribology or both.