Average and center temperature vs time evaluation for freezing and thawing rectangular foods

A numerical solution of the heat transfer partial differential equation and equations for predicting effective heat capacities, enthalpies and thermal conductivity were used to determine the thermal response of objects placed in cooled air freezing units. Central temperatures of a rectangular meat patty for one and two dimensional heat transfer were predicted and compared with experimental results. Times to reach an enthalpy average temperature were calculated by the program. Differences between the times obtained with the same average and central temperature depend on heat transfer rate and can represent 12% of the time involved.