Food irradiation is the process of exposing food to a controlled amount of energy called "ionizing radiation." There are three different types of radiation allowed: electron beam radiation.
• Gamma rays : Gamma rays are produced by radioactive substance (Cobalt-60 or Cesium-137) that continuously emits high-energy gamma rays. gamma rays can penetrate deep into food.
• X-rays : produced by machine called electron acceleration produce energy for X-rays.X-ray can be focused in a small area.
• Electron beam radiation : produced by machine called electron acceleration. Electron beams are only able to penetrate 1 to 2 inches.
How are foods irradiated?
The food irradiation typically involves moving prepackaged foods on a conveyor into a thick-walled room and exposing it to the radiation source. Depending upon the nature of the food, it will be exposed to gamma rays for 15 to 45 minutes, or to an electron beams for several seconds up to several minutes. Either the food or the source of irradiation can be moved and rotated during exposure to ensure that the radiation evenly penetrates the foods. When the gamma ray irradiation process is complete, the rods of radioactive material are retracted into a pool of water, which acts as a radiation barrier. When the electron beam irradiation process is complete, the electrical source is turned off.
Why irradiate food?
Ionizing radiation can penetrate food, killing microorganisms without raising the temperature of the food significantly. Food irradiation is used to:
• prevent food poisoning by reducing the level of harmful bacteria, such as E.coli O157:H7 in ground beef and Salmonella and Campylobacter in poultry; and parasites which cause food-borne diseases;
• prevent spoilage by destroying bacteria, molds and yeast which cause food to spoil, and control insect and parasite infestation, and;
• Increase shelf life by slowing the ripening or sprouting in fresh fruits and vegetables, thereby allowing for longer shelf life.
It is possible for irradiated food to become contaminated after it has been treated. For this reason, proper storage, handling and cooking are very important.
Is eating irradiated foods safe?
Extensive research and testing have demonstrated that irradiated food is safe. Scientists from the U.S Food and Drug Administration, the U.S Department of Agriculture, the U.S department Energy, and universities demonstrated that irradiated food is safe. Scientific committees in Denmark, Sweden, the United Kingdom, Canada, and the World Health Organization also have endorsed food irradiation. Food irradiation has been approved in 37 countries for more than 40 products.
Does food irradiation guarantee food safety?
No, nothing can guarantee food safety, but food irradiation reduces the bacteria and other microorganisms that may be present on food. Irradiated food must be handled properly like other foods to prevent re-contamination.
What are the labeling requirements?
Irradiation food products are labeled, mot as warning but as a source of information for consumers. All packages of irradiated food carry the green, international radiation sign, as well as the words "Treated with radiation" or "Treated by irradiation" the handling statement "Keep Frozen" or "Keep Refrigerated" also must be present.