Use of simple thermal conductivity models to assess the reliability of measured thermal conductivity data

Thermal conductivity data are important for modelling thermal processes and designing refrigeration systems. The literature contains a large number of data for food products, but many are questionable, whether due to typographical errors during publication, indirect measurement methods or inherent variability in the properties of the food itself. This paper describes a method by which the reliability of thermal conductivity data can be checked using simple thermal conductivity models and basic heat transfer theory, provided composition data for the foods are available, or may be assumed based on foods with similar composition. The method is applied to a variety of foods to serve as worked examples. It is recommended that these models be used to check the credibility of measured data before they are published, and also to check published data before they are used in any calculations.