A New Water Sorption Equilibrium Expression for Solid Foods based on Thermodynamic Considerations



Solution thermodynamics was used to derive a new semitheoretical expression to represent sorptional equilibrium in food products having both temperature and water content as independent variables. A number of correlations have been studied and compared with the proposed equation using different requirements, necessary for their application in mathematical modeling and engineering calculations. These criteria were their capabilities to fit the experimental data, to evaluate the derivatives and the heat of sorption, and to predict the behavior at high moistures. On this basis, it was concluded that the present expression provided an accurate description of the sorptional behavior for many food systems.