Gamma-Radiation Sensitivity of Pathogenic Bacteria in Beef

The gamma-radiation sensitivity of eight kinds of pathogenic bacteria related to beef was investigated in frozen cells with 0.1 M phosphate buffer and inoculated cells in beef. In frozen cells, D10 values of pathogenic bacteria related to beef were kGy, and inactivation factors were at the radiation doses of kGy. Beef was inoculated with Escherichia coli, Pseudomonas aeruginosa, Salmonella typhimurium, Enterobacter aerogenes, Vibrio parahaemolyticus, Staphylococcus aureus, Listeria monocytogenes, and Aeromonas hydrophila. Inoculated beef samples were packaged in air and irradiated at 0.005 to 3.0 kGy. Ninety percent of the viable pathogenic bacteria in beef was eliminated by doses of kGy at room temperature, and the inactivation factors were kGy at the radiation doses of kGy. Therefore, irradiation is considered to be an effective method to control pathogenic bacteria in beef.