Linear and Nonlinear Rheology of Mixed Polysaccharide Gels. Pt. II . Extrusion, Compression, Puncture and Extension Tests and Correlation with Sensory Evaluation

We report on an extrusion test and its correlation with sensory perception. The extrusion test was implemented on a texture analyzer and applied to single‐component or composite polysaccharide gels. The extrusion force did not depend strongly on the volumetric flow rate, indicating a predominantly elastic contribution to the force. The extrusion force correlated highly with sensory perception of the cutting effort and its ratio to the elastic modulus correlated highly with perception of the extensibility. A combination of the Young's modulus and the extrusion force correlated well with perception of firmness. The robust correlations depended weakly on the flow rate in extrusion, but were much higher for tapering ratios T ≥ 4.5 than for T = 2.5. Notably, the correlation obtained was higher than that with texture profile analysis parameters. We show the correlation of several empirical and fundamental large deformation tests with texture, and suggest that the higher correlation with extrusion reflects the closer mixed‐mode deformation in mastication. Practical Applications The report highlights correlation of parameters from empirical and fundamental rheological tests with sensory evaluation. The forces generated in an empirical extrusion test emerge as appropriate and reliable descriptors of several sensory attributes. The approach outlined is appropriate in general for textural mapping of semisolid and solid foods with an apparent yield stress.