Heat treatment of milk: Microwave technology and ohmic heating

Microwave and ohmic heating represent established processing technologies that provide volumetric heating. Interest in the application of these technologies in dairy (and more general food) processing has grown in the recent past, driven by economic, environmental and societal pressure to improve the sustainability of dairy production and processing by reducing the carbon footprint of operations. Microwave and ohmic heating are of interest because they use electricity (sourced from renewables where possible), rather than hydrocarbons as a source of energy. Immediate applications in dairy processing include the potential to thermally treat viscus products such as yogurts; to provide the basis for novel dairy product structuring; and to dramatically decrease fouling and corrosion of heating equipment. This chapter provides the reader with a brief overview of the principles of microwave and ohmic heating, and how these technologies can be applied in dairy processing.