The Psychophysics of Pouring, Spreading and In‐mouth Viscosity

The sensory viscosity of low calorie viscoelastic syrups in the mouth, while pouring out of a bottle, and spreading over a flat surface was satisfactorily estimated from the fundamental physical properties of these fluids. Appropriate sensory perception mechanisms were identified and linked to the operating conditions of each sensory test through psychophysical models. Oral sensory viscosity correlated with the shear stress in the mouth (R2= 0.96) (Kokini et al. 1977); pouring sensory viscosity correlated with the cross sectional area filled by the fluid at the neck of the bottle (R2= 0.86); and spreading sensory viscosity correlated inversely with the radial growth of the spreading fluid puddle (R2= 0.96).