Quality & Sensory

Thixotropy

A time-dependent decrease in viscosity under constant shear, with recovery on standing.

Real-life application

Why tomato ketchup flows more easily after shaking or stirring but thickens again once left standing.

Related terms

The study of deformation and flow. Newtonian fluids have constant viscosity; non-Newtonian fluids do not.

A fluid whose shear stress is directly proportional to shear rate, so viscosity is independent of shear.

Practise the subject behind the definition.