Stress-relaxation test to evaluate textural quality of frozen stored Cape hake (M-capensis and M-paradoxus)

A stress-relaxation test was developed for frozen stored Cape hake (M. capensis and M. paradoxus) to he used as a quality assessment tool. Fish was compressed by 5% and deformation was kept constant for 60s. The resulting relaxation curves were fitted to different multiexponential regression models. A three-term exponential fit without a residual term was chosen as the best model. Relaxation parameters from this test correlated well with sensory texture attributes derived from the quality index method (QIM). The high degree of correlation (0.90) suggests that these relaxation parameters could be used as markers for evaluating textural quality of frozen Cape hake, replacing sensory assessment. The regression model was: STA = 0.117 divided by 0.967 RP (where STA = PCI from sensory texture attributes and RP = PCI from relaxation parameters), with P < 0.001. (C) 2004 Elsevier Ltd. All rights reserved.