A novel method for evaluating viscosity and viscoelasticity of liquid foods by a non-rotational concentric cylinder setup

Abstract

A concentric cylinder system without plunger rotation was applied in this study. The theory and method were based on analyzing shear stress acting on the surface of plunger when the plunger moved upward or downward a very small distance at a constant speed. Sample used were sucrose solutions, French dressing, tomato catsup, mayonnaise, etc. The viscosity of these samples could be evaluated from the force measured just after the starting time of the plunger moving (theoretically, t =0). The viscoelasticity was also evaluated by analyzing the change in force during the plunger movement for a quite small distance.