The objective of the present study was to examine the influence of the level of added water (21-29%), fat (12.4-29.7%) and salt (0.42.4%) on radio frequency (RF) and microwave (MW) dielectric properties. Selected thermal properties and temperature rises (Delta T) following standardised MW or RF heating protocols were also measured. Results revealed that added salt had a major impact on dielectric properties and Delta T though no impact on thermal properties was noted. Fat had an influence on thermal properties and a lesser influence than salt on dielectric properties, though no significant effect (P >= 0.05) on Delta T was found across the range examined. The high inherent moisture content of the lean used made it difficult to isolate the impact of added water as increasing its addition level decreased the amount of added lean resulting in no net change in the moisture content across the range examined. (c) 2006 Elsevier Ltd. All rights reserved.