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The food irradiation process is a simple one. The new U.S. plant， Vindicator of Florida Incorporated in Mulberry， Fla.， uses a material called cobalt 60 to irradiate food. Cobalt 60 is radioactive isotope （form） of the metallic element cobalt. Cobalt 60， which gives off radiation in the form of gamma rays， is also used for radiation therapy for cancer patients and for sterilizing hospital equipment. The radioactive isotope is created by bombarding cobalt with subatomic particles in a nuclear reactor. However， irradiation plants do not themselves contain nuclear reactors.

In the irradiation plant， food is exposed to thin rods of cobalt 60. The rods give off gamma rays， which disrupt chemical processes in contaminating organisms. The disruption breaks down the cell walls of organisms or destroys their genetic material. The dose， set by the U.S. Food and Drug Administration （FDA）， is enough to kill organisms on food， but not enough to produce significant changes in the food itself.