In a first part, classical equations were searched in the literature, which were reported to predict the initial freezing temperature, the thermal conductivity and specific heat of a food product in function of its composition and temperature. These equations were coupled to the Tchigeov’s method, which predicts the ice fraction formed in temperatures below the freezing point for a food material. This procedure enabled the prediction of the thermal properties and the development of the functions enthalpy (H) and Kirchhoff (E) with respect to the temperature for the studied product by numerical integration. The second part consists in the development of a computational code in finite differences to solve the transient heat conduction equation, transformed by the introduction of the enthalpy and Kirchhoff functions. The use of the Kirchhoff and enthalpy functions is reported in the literature to minimize numerical oscillations. This model was used to fit experimental timetemperature data carried out with green beans freezing using five different air speed protocols. The procedure results in a useful method to predict the temperature evolution within a food product subjected to a freezing process.
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