A quick, reliable solution for modelling cheese chilling process

Abstract

Optimisation of the refrigerating system for cheese processing requires an accurate prediction of chilling time, product temperature distributions and heat flow. Many existing CFD models can provide the best predictions by directly solving the three-dimensional heat transfer problem within the product and for air flow around the product; however, they are time-consuming and not suitable for routine use. A one-dimensional numerical solution proposed by Ghraizi, Chumak, Onistchenko, and Terziev (1996) has been used to provide the quick answer to food processing engineers with a good accuracy. In this method, the partial differential equation describing one-dimensional non-linear unsteady heat conduction inside the product has been solved by a finite difference technique. The method can take into account the temperature-dependence of thermal properties of foods and a general shape factor was used to reflect the product geometry. The model was applied to a single block of cheese, and agar. Predicted results are compared to experimentally-measured temperature profiles as well as to results generated by the Food Product Modeller, FPM, software.