Sensory texture attributes of firmness (manual, oral, shear and compression), elasticity and type of breakdown of gelatin, sodium alginate, and kappa‐carrageenan gels at two concentrations, were evaluated by 18 experienced judges. Nine of the judges also evaluated oral temporal responses to firmness and sourness. The Instron Universal Testing Machine (IUTM) was utilized to measure compression and shear at 200 mm/min at varying deformations. Gelatin was the firmest and most elastic of the three gels. During mastication it broke down into a few large pieces. Carrageenan produced the least firm and least elastic gel which failed into a large number of small pieces. Time‐intensity recordings demonstrated that more oral manipulation time was required to break down carrageenan and alginate gels in contrast to thermally‐degradable gelatin gel. Whereas perceived oral firmness reached a maximum in less than 5 s after placement of a gel sample in the mouth, maximum sourness was not perceived until 13‐18 s. Greater discrimination between gel concentrations was obtained by sensory than by mechanical measures, and beyond rather than below the yield point. Estimates of sensory firmness by shearing were highly correlated with each other and with mechanical shear and compression force. Manual compression correlated only with surface rupture force, while oral compression correlated only with shear maximum force.

Eighteen experienced judges evaluated the texture of gels varying in gelatin concentration (22‐45 g/L) in terms of firmness by oral and manual shear and compression, cohesiveness, and extent of breakdown in the mouth. Manual compression and biting with the front teeth discriminated well across gel concentrations. All sensory measures except extent of breakdown increased with gelatin concentration. Instron (IUTM) measurements showed that increasing gelatin concentration resulted in an increase in maximum force and force/deformation, but had little effect on deformation at yield and rupture or in elasticity and cohesiveness. Results from mechanical measurements varied with the type of force applied (compression, shear or puncture), the loading rate (50 or 200 mm/min), and the extent of deformation attained (40–90%). The highest discrimination across gel concentrations was achieved with shear force at a rate of 200 mm/min and at greater deformations. Sensory responses correlated most highly with the following IUTM measurements: (1) Compression forces at yield and at deformations of 70 and 85% at the higher crosshead speed; (2) Compression forces below the yield point at the lower crosshead speed; and (3) Shear forces measured at maximum deformation (90%) at 200 mm/min.

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