Water sorption and cooking time of red kidney beans (Phaseolus vulgaris L.): part II – mathematical models of water sorption

Abstract

SummaryEmpirical, semi‐theoretical and finite element method (FEM) models were developed to simulate the water sorption of kidney beans. The data of bean moisture content and 1 D swelling ratios obtained in Part I were regressed at different soaking times, and these regression models were used to update the boundary condition and calculate the node coordinates of the FEM model. The developed models were used to calculate the effective water diffusivity (Deff). The developed new empirical model, which considered the soaking temperature and pretreatment history of beans, was the best‐fit equation. The trend of the Deff calculated by the semi‐theoretical model was inconsistent with the water sorption of the beans. The Deff value predicted by the FEM was from 10−3 to 10−7 m2 s−1 and it decreased with the increase in soaking time. There was no significant difference between the moisture contents measured and predicted by the FEM.