Influence of deformation rate and degree of compression on textural parameters of potato and apple tissues in texture profile analysis

The influence of the degree of compression, at deformation rates of 50, 250 and 500 mm min(-1), on the textural parameters in the texture profile analysis (TPA) of cylindrical samples of potato and apple tissues was examined. The tests were performed at up to eight different deformation levels ranging from 10% to 80%. The values of all the parameters measured in the samples of both tissues were influenced more by the degree of compression than by the deformation rate. Degrees of compression greater than 40% and 20% caused the rupture of potato and apple specimens, respectively. Regression models were fitted to express the variation of cohesiveness and chewiness with deformation rate and degree of compression. In apple and potato tissues, the degree of compression had a quadratic effect on the cohesiveness while the effect of the deformation rate was only linear. Cohesiveness was the most appropriate textural parameter for detecting effects of deformation rate and degree of compression in TPA tests of potato and apple tissues. Recoverable instantaneous springiness offers a high potential to differentiate the structural natures of different tissues.