Kinetic modeling and thermodynamic properties of soybean cultivar (BRS257) during hydration process

摘要

The hydration kinetics of transgenic soybean cultivar BRS257 was studied at temperatures 30, 40, 50, and 60 degrees C for 480min. Peleg and Omoto-Jorge models and its generalized equations were used in this work to describe the kinetics of water absorption. At all temperatures, the models represented the main trends of the hydration process with deviations of less than 3%. However, the Peleg model presents the best fit to the experimental data (R-2=0.99; P<3.0%; RMSE=0.97; SE=1.07). The moisture transfer is affected by temperature, with higher absorption rates at higher temperatures and the Peleg's constant K-1 decreased, while K-2 was almost constant. The activation energy (E-a)=-34.797kJ/mol and average enthalpy (H)=-37.442kJ/mol, entropy (S)=-1.917E-01kJ/mol/K, Gibbs free energy (G)=2.347E+01kJ/mol were estimated from the adjusted parameters and Arrhenius equation. The values obtained show that hydration is not a spontaneous phenomenon. The grain density (0.970.08 g/cm(3)) presented almost constant values during the experiments.