Food Irradiation


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What is Food Irradiation?

Food irradiation is, most simply, a means of food preservation to extend product shelf life. It is a process of exposing food, either pre-packaged or in bulk, to very high-energy, invisible light waves (radiation). Irradiation can be an effective way to treat many problems in our food supply, such as insects in grain, sprouting of potatoes, rapid ripening of fruits, and bacterial growth.

Gamma irradiation may be compared to turning on a light, illuminating a room, and turning it off again. Gamma rays pass into foods, affect the food or target organism, and leave the food. How the rays affect the food depends on the food, and the organisms in the food. But you are probably more familiar with common medical uses of radiation: medical and dental x-rays, detection and treatment of diseases, sterilizing medical equipment and devices and pharmaceutical products, and producing sterilized food for special hospital diets. It’s also been used to increase the brilliance of precious stones.

How does food irradiation work?

Short-wave radiant energy is absorbed by food and causes a variety of chemical and physical reactions, such as stopping sprouting or killing insects. These reactions target cellular components, not nuclear changes in the atoms that make up food. The amount of energy the food absorbs is controlled so the changes have desirable food preservation effects while maintaining the safety and wholesomeness of the food. The food itself does not become radioactive. Even though food has been irradiated to extend its shelf life, you still must refrigerate perishable foods.

What are the benefits?

The potential benefits of food irradiation are impressive, including reduction of:
  • postharvest losses, which means less food waste
  • chemical residues in foods by replacing fumigants and other pesticides
  • the risks of food borne illness from bacteria
  • the risk of trichinosis in pork

Although some radiation treatments were first approved in 1963 to control insects in wheat and flour, the last decade has seen an increase in the application of this food preservation technology. More than 30 countries have approved food irradiation technologies to ensure food quality and safety. Currently, only spices, herbs, and selected fruits and vegetables are commercially available in irradiated form. To prepare for expanded use of the technology, Food and Drug Administration has approved label requirements to let the public know when a food has undergone irradiation. An international symbol features a stylized plant inside a broken circle. The symbol is to be accompanied by the statement "treated with radiation" or "treated by irradiation."

Studies seems to indicate that as knowledge and awareness of the technologies increase, so might its acceptance among FACSs. The food industry will continue to respond to the wishes of the public, but also wants the public to know the benefits of this technology.