Evaluation of Physical and Chemical Techniques for Decontaminating Food and Food Contact Surfaces

A range of novel surface decontamination methods for treating food and food contact surfaces have been evaluated. A unit based “cold steam” that was generated by heating water under high pressure and temperature was shown to support reduction >4 log cfu of E. coli and Listeria on a range of surfaces (stainless steel, cutting boards and agar plates). However, bacterial inactivation was more associated with thermal effects as opposed to generation of free radicals. Hydroxyl radical generators supported reduction of bacteria on surfaces including lettuce. However, it was unclear if the antimicrobial effect was due to drying effects or via radical formation. Coatings based on titanium dioxide and cocamidoropyl betaine could inactivate vegetative cell inoculated on food contact surfaces although Bacillus endospores were resistant. The most effective treatment evaluated was acidic electrolyzed water that could decontaminate a range of food and contact surfaces without detrimental effects. King Saud University, Saudi Arabia