These shorter wavelengths are capable of damaging microorganisms such as those that contaminate food or cause food spoilage and deterioration. Irradiation is known as a cold process. It does not significantly increase the temperature or change the physical or sensory characteristics of most foods. Food is irradiated to provide the same benefits as when it is processed by heat, refrigeration, freezing or treated with chemicals to destroy insects, fungi or bacteria that cause food to spoil or cause human disease and to make it possible to keep food longer and in better condition in warehouses and homes. Because irradiation destroys disease causing bacteria and reduces the incidence of food borne illness, hospitals sometimes use irradiation to sterilize food for immuno-compromised patients.
Irradiated foods are wholesome and nutritious.
All known methods of food processing and even storing food at room temperature for a few hours after harvesting can lower the content of some nutrients, such as vitamins. At low doses of radiation, nutrient losses are either not measurable or are not significant. At the higher doses used to extend shelf-life or control harmful bacteria, nutritional losses are less than or about the same as cooking and freezing. As in the heat pasteurization of milk, the irradiation process greatly reduces but does not eliminate all bacteria. Irradiated poultry, for example, still requires refrigeration, but would be safe longer than untreated poultry.