Numerical simulation of temperature histories of frozen minced meat having different fat contents during ohmic thawing

Abstract

The ohmic thawing (OT) of minced meat sample was mathematically modelled using different numerical methods (Finite Difference-FD and Finite Volume-FV) for different process conditions (voltage gradients of 10, 13 and 16 V/cm and fat contents of meat sample as 2%, 10% and 18%). FD method was successful to predict the temperature changes for both heating and phase change regions. FV method was performed by using two different heat generation functions; depending on process time (UDF-1) or the center temperature (UDF-2). The description of the change of heat generation term depending on process time (UDF-1) in the ANSYS module was more successful with the experimental data compared to the description of the change of heat generation term depending the center temperature (UDF-2). Although FV model is more complex than FD model it can be applied for simulation of detailed temperature distributions. On the other hand, FD model can be applied for practical predictions of temperature histories for center temperatures in simple geometries. It is thought that the simulation of OT performed at different conditions with the FD and the FV methods would contribute valuable data in the design of household ohmic thawing/cooking systems for solid food materials.