The applicability of the GAB model to food water sorption isotherms

The fitting ability of the GAB equation has been analysed. It has been shown that the GAB model describes well sigmoidal type isotherms when parameters are kept in the following regions: 0.24 7lt; k ≤ 1 and 5.67 ≤ c ≤ ∞. Outside these regions the isotherm is either no longer sigmoidal or the monolayer capacity is estimated with the error larger than ± 15.5%. Moreover, keeping constants in the above regions fulfils the requirements of the BET model.