Prediction of enthalpy and thermal conductivity of frozen meat and fish products from composition data

In this paper we present models predicting thermophysical properties of frozen meat products purely using their composition data. Based on our previous model, predicting the water activity of (frozen) meat and fish products, while taking into account the non-ideality of the unfrozen solution, we can compute the ice fraction as a function of temperature. Knowing the composition and ice formed, the temperature dependency of heat capacities and latent heat, we can readily compute the enthalpy. For predicting the thermal conductivity a model is constructed taking into account the meat (fibrous) structure, the anisotropy of ice cyrstals, and the distribution of the composition over dispersed and continuous phases. Comparison model predictions to literature data on enthalpy and thermal conductivity shows that we can obtain reasonable prediction within engineering accuracy of 10%. The thermal conductivity model gives significant differences in conductivity parallel and perpendicular to meat fibres, in accordance with experimental data. (C) 2007 Elsevier Ltd. All rights reserved.