Project Number: 0500-00031-001-02
Project Type: Specific Cooperative Agreement

Start Date: Jul 01, 2005
End Date: Jun 30, 2010

Objective:
To ensure the safety of channel catfish and other aquaculture species to the consumer. With the dramatic increase in production, processing and consumption of aquaculture products, there is a requirement to understand and reduce the food safety risks, both chemical and microbiological associated with these products. The project is to asssess the influence of microbial catalase as a means of determining thermal process verification of cooked catfish. In the various experiments, inactivation of enzyme will be monitored by specific stain electrophoresis. Preliminary data suggest that catalase is not an acceptable enzyme indicator. Alkaline phosphatase will again be tested as an alternative enzyme.

Approach:
Study the influence of CO2 and ozone gas during refrigerated storage on shelf life and selected pathogens inoculated on catfish. Evaluate the microbial load of fish in a processing line to discern critical point(s) that will enhance the shelf life of iced fillets. Develop effective means of sanitation of catfish processing plants. Study the effect of pre-harvest, harvest, and post-harvest practices on quality and safety of catfish. Conduct experiments to determine the genetic basis for the variation in expression of LLO, PI-PLC, and PC-PLC between the virulent L. monocytogenes strain EGD and avirulent strains. Confirm results using a limited number of L. monocytogenes isolates along with one known virulent strain and one known avirulent strain using a mouse assay.