The Use of Fractional Conversion Technique to Investigate the Effects of Testing Parameters on Texture Degradation Kinetics

To study the effects of testing parameters on texture degradation, texture loss of potatoes heated at 80 °C was measured using an Instron universal testing machine as well as a texture analyzer under 2 instrument crosshead speeds, 2 sample sizes, and either compression or shear modes of mechanical deformation. Using the fractional conversion as a texture index, the kinetics of texture degradation of potatoes fitted a single 1 st order reaction model, and the rate constant (or D value) was shown to be independent of the test used to determine the texture index. The average D value was 30 ± 1.2 min at 80 °C.