A new method for predicting sorption isotherms at different temperatures: Extension to the GAB model

• The methodology for parameter estimation using less experimental data was extended to the GAB model.
• The GAB parameters are estimated using one single sorption isotherm and one single value of Qs.
• The resulting set of parameters can be used to predict sorption isotherms at different temperatures.
• Different food materials were successfully tested providing good fitting and prediction results.

In this work, the new methodology for parameter estimation using less experimental data proposed in Staudt et al. (2013) is extended to be used with the GAB model. In addition, a modification in the Arrhenius form for temperature dependency of the energetic constant C is proposed in order to avoid numerical instabilities during parameter estimation. When compared to the original work, one additional parameter, k needs to be estimated but still only one isotherm and one value of net isosteric heat of sorption is required to build the whole set of sorption isotherms. Different food materials were successfully tested providing good fitting and prediction results attesting that the advantages of the methodology originally developed for the BET model are kept with the GAB model.