Microbial inactivation of liquids
PEF for mild food preservation
Pulsed electric field processing can inactivate micro-organisms. It is a non-thermal food preservation technique. Unlike thermal pasteurization PEF does not affect vitamins, proteins and other valuable nutritional and functional components. Electroporation applied for food preservation produces high quality, fresh like liquid foods and beverages.
Electroporation has a targeted impact on cell membranes. Whereas all kinds of vegetative spoilage and pathogenic microorganisms can be inactivated, a limited effect on enzymes, spores and viruses is found. Other constituents such as vitamins, minerals, pigments and flavors are also retained. In contrast to heat treatment the functionality and nutritional value of proteins is hardly affected.
For heat-sensitive liquid foods where thermal pasteurization is not an option, PEF treatment would be advantageous.
To achieve microbial inactivation, a higher treatment intensity is required than for cell disintegration only, limiting the applicability to pumpable products with a particle diameter of less than 20 mm.
In general, the shelf life of PEF-treated and thermally pasteurized foods is comparable. Like thermally pasteurized foods PEF-treated products are usually stored refrigerated.
However, the usage of PEF for food preservation is not limited to mild pasteurization purposes. Food sterilization is possible with PEF in combination with higher temperatures to eliminate spores.
For mild preservation of fruit juices a typical processing line consists of a supply tank, a fluid pump, a pulse generator unit, a cooler (if required) and a buffer tank. The Pulsemaster Conditioner is a complete system for this type of food decontamination.These processing lines can be CIP (Clean In Place) or SIP (Steam In Place) cleaned.