Paper for IOA Pan American Group Ozone Conference, Oct 1st-4th 2000, Orlando, Florida Category: Food Applications Format: oral presentation

Environmental Application in Food Processing Facility using Ozone Ed Steiner and James Yuan AIR LIQUIDE 5230 S. East Ave. Countryside, IL 60525 Abstract Food safety problems come from many different sources and can be quite complex. A major source of contamination comes from the work environment and/or the processing surfaces and implements. Post or cross contamination from either the environment or food contact surfaces has been implicated in up to 30% of food poisoning cases. For example, Listeria spp., an environmental pathogen, was the cause of 1850 reported cases of listeriosis of which 425 people died, according to the Center for Disease Control in 1998. Post or cross contamination can also increase the microbial load in a finished product, which could result in shelf-life reduction. This could also lead to significant economic losses as well as possible consumer health issues. The effective use of a sanitizer/disinfectant can be a key factor in the ongoing effort to prevent, eliminate or minimize microbial contamination of foods. Most studies have looked at the use of ozone for decontaminating product surfaces or water. The purpose of this study was to investigate the efficacy of ozone in reducing microbial contamination of the environment (e.g. air), food contact surfaces (e.g. food processing equipment). Both gaseous and aqueous ozone was used during these experiments. Gaseous ozone was applied to study its effectiveness on the air disinfection in the processing room. An air sampler was used to collect samples. Ozonated water was applied to sanitize food contact surfaces. Various food-processing surfaces, including the floor, were treated with ozonated water, at several different concentrations. These surfaces were then swabbed to remove surviving bacteria, serially diluted, and plated on a selective microbiological medium. Preliminary results showed that the use of ozone in the environmental applications was effective at either reducing or controlling microorganisms from the initial levels tested. Typically reductions between one and two logs (90-99%) occurred with ozonated water. At an ozone level of 2 ppm, off gassing was minimal. The experiments also showed that microbial levels on the food contact surfaces did not increase during processing. However, these levels did tend to increase when the surfaces were rinsed only with water.