food irradiation

The most recent addition to food preservation technologies is the use of ionizing radiation, which has some distinct advantages over conventional methods. With irradiation, foods can be treated after packaging, thus eliminating post-processing contamination. In addition, foods are preserved in a fresh state and can be kept longer without noticeable loss of quality. Food irradiation leaves no residues, and changes in nutritional value due to irradiation are comparable with those produced by other processes. Irradiation is the process of applying high energy to a material, such as food, to sterilize or extend its shelf-life by killing microorganisms, insects and other pests residing on it. Sources of ionizing radiation that have been used include gamma rays, electron beams and X-rays. Gamma rays are produced by radioactive isotopes such as Cobalt-60. Electron beams are produced by linear accelerators, which themselves are powered by electricity. The dose applied to a product is the most important factor of the process. At high doses, food is essentially sterilized, just as occurs in canning. Products so treated can be stored at room temperature almost indefinitely. Controversial and banned in some countries. (Source: IFSE / VCN)