Pulsed electric fields (PEF) applications in food processing - process and equipment design and cost analysis

The impact of pulsed electric fields (PEF) on plant and animal as well as microbial cell membranes was investigated. It was shown that extractability of fruit and vegetable juices and intracellular compounds can be enhanced after a PEF-treatment. A PEF-treatment of meat pieces resulted in enhanced mass transfer during drying as well as brining of products, an improvement of water binding during cooking was found due to improved micro-diffusion of water binding agents. Inactivation of E. sakazakii, L. monocytogenes and other pathogens was investigated in different heat sensitive liquid media, by variation of processing parameters optimum treatment conditions for a gentle and energy efficient increase of shelf life have been identified for raw milk, nutrient or vitamin solutions. To separate thermal and PEF effects kinetic studies have been performed. A combined application of PEF and mild heat showed highly synergetic effects and improved energy efficiency. Technical and industrial scale equipment has been developed at DIL and will be presented along with a discussion of costs of investment and operation.