Prediction of the freezing point of multicomponent liquid refrigerant solutions

The freezing point is one of the most critical properties required to complete the mathematical formulation related to the transport phenomena involved in the immersion chilling and freezing (ICF) of foods. Unfortunately, data for ternary and higher order systems are scarce. The aim of this work was to verify the validity of an excess Gibbs energy model for predicting the freezing point of multicomponent mixtures of electrolytes and non-electrolytes, considering the processing conditions used in immersion chilling and freezing of foods. The extended UNIQUAC model was used. Data obtained from literature corresponding to freezing points of the ternary systems: NaCl-KCl-H2O, NaCl-CaCl2-H2O, NaCl-MgCl2-H2O and NaCl-EtOH-H2O, were compared with predicted values. The model accuracy was satisfactory, the highest absolute deviation being smaller than 1.71 degrees C for the 378 data compared. (C) 2010 Elsevier Ltd. All rights reserved.