Rheological characterization of a model food suspension containing discs using three different geometries

The objective of this study was to characterize the flow behavior of a soli d-liquid food model which imitates Mexican sauces. The model food suspensio n consisted of seeds suspended in a shear-thinning fluid (Avicel and Xantha n gum). The effects of size and particle concentration were investigated us ing a traditional disc geometry in wide gap (spindle), and a ribbon adapted to a rotational viscometer. The effect of particle size was evaluated in a tube viscometer. Power-law parameters and apparent viscosity were estimate d in the shear range of each viscometer. The experimental apparent viscosit y showed good agreement with predictions obtained using a theoretical expre ssion of relative viscosity for uniform spheres. In all the viscometers inv estigated, shear-thinning behavior of the suspension was observed, as the a queous phase, due to low interactions among particles. The ribbon geometry appears to be the best option for flow characterization of food suspensions containing coarse disc shaped particles.