Optimum Radiation Dose to Eliminate Listeria monocytogenes in Packaged RTE Processed Meats and Survival of Listeria monocytogenes in RTE Processed Meats after Irradiation Processing

Objectives

To determine the ability of Listeria monocytogenes to attach to RTE processed meats (sliced roast beef, turkey ham, sliced bologna and frankfurters); the optimal radiation dose required to eliminate Listeria using an electron beam source; and the survival of L. monocytogenes in RTE after irradiation processing.

Conclusions

L. monocytogenes showed higher sensitivity to irradiation in roast beef and turkey ham with D10 values of 0.523 and 0.526, respectively. L. monocytogenes seemed to be more resistant in bologna and frankfurters with D10 values of 0.549 and .0638, respectively. Survival and growth of L. monocytogenes in the same RTE products after irradiation at doses of 2.0 and 4.0 kGy was studied during storage at temperatures of 4oC and 10oC for 12 weeks. No survivors were observed in samples irradiated at 4.0 kGy. A 2.0 kGy dose was successful in reducing the numbers of Listeria and storage at 4oC proved to be effective in suppressing the growth of the organism for about 5 weeks after irradiation. Storage at 10oC allowed the growth of higher numbers of L. monocytogenes in all products. L. monocytogenes exhibited minimal or no growth when examined in roast beef samples. Survivors growing on bologna, frankfurters, and turkey ham presented good growth.

Deliverable

This study established optimum irradiation dosage levels for various RTE meat and poultry products.