Correlation of human perception in swallowing with extension rheology and tribology characteristics in comparison with shear rheology.

Correlation was investigated between instrumental characteristics obtained by extension rheology or tribology measurements and human perception while swallowing using aqueous solutions of xanthan gum and locust bean gum. Extension viscosity and the friction coefficient were measured using a capillary breakup rheometer and a rotation tribometer respectively as in our previous study. Results were compared with shear viscosity to clarify novelty and advantage of these mechanical parameters. It was indicated that perceived cohesiveness correlated the highest with the maximum extension viscosity immediately after the onset of extensional flow, perceived spinnability did with extension viscosity in high Hencky strain region, and perceived sliminess did with the friction coefficient at the critical point between the boundary lubrication and the mixed lubrication. These correlations were discussed and tried to validate considering biomechanics of human swallowing and food-human interactions. This article is protected by copyright. All rights reserved.