New parameters for instrumental texture profile analysis:: Instantaneous and retarded recoverable springiness

Cylindrical samples of gelatin, kappa-carrageenan/locust bean gum and gellan gum gels were subjected to two successive cycles of compression at three predetermined deformation levels corresponding to 25, 50 and 75% of their respective degrees of compression at failure. Values of "recoverable instantaneous springiness" (S-ins) and "recoverable retarded springiness" (S-ret) were measured. Values of S-ins and S-ret for the gelatin samples were similar and close to 1, indicating a very fast and almost complete recovery of their initial height. By contrast, for kappa-carrageenan/locust bean gum and gellan gels the values of S-ins and S-ret were quite different, indicating that recovery was retarded. These parameters seem to be a good index of the relative magnitude of elastic and viscous components of foods. This was confirmed by relaxation tests.