Abstract
The first-order kinetic of a two-component system was applied to investigate the thermal property of tomato juice. The commercial Mathcad program package was used to calculate the necessary parameters from the experimental data for the model. The thermostable and thermolabile enzyme populations in the juice were 2. 0% and 98. 0%, respectively. The Zs and Zl values of thermal destruction curves for the thermostable and thermolabile pectinesterase enzymes were 8. 3°C and 7. 0 °C for the temperature range of 75-90°C, respectively. The calculated Z's value were in good agreement with the literature values for tomato juice. The calculated and experimental nonlinear thermal property curves for tomato juice were in good agreement at a wide range temperature of 75-90°C.
