A Focus on Food Irradiation

Back to top On this page... Food Irradiation Research Areas Food and Drug Administration (FDA) approved irradiation in the United States for What can Irradiation do Approved dosages for US Irradiation Resources How Food Irradiation Works Applications of Food Irradiation Regulators of Food Irradiation Irradiation Technologies Public Interest Resources Organizations Opposing Food Irradiation Organizations Supporting Food Irradiation Food Irradiation Research Areas Radioactive safety for consumers Combining beneficial effects of irradiation and other ingredients to improve sensory cahracteristics. Affects of Vitamin E on meat quality including odor and color after irradiation Radiation sensitivity of foodborne pathogens with foods of varying starting temperatures Reducing processing costs Improving consumer acceptance Back to top Food and Drug Administration (FDA) approved irradiation in the United States for Wheat and Wheat Flour – first approval to rid plants of insects, 1963 NASA sterilizes meat for astronauts in space, 1972 Pork products- controlling trichinosis, 1985 Spices, tea, fruits, vegetables, grains – eliminating insects, 1986 Fresh and frozen poultry - controlling Salmonella, other bacteria, 1990 Fresh and frozen red meats such as beef, lamb and pork - Pathogen control, 1997 Fresh shell eggs, 2000 Animal feed ingredients, including pet treats - reducing risk of Salmonella contamination, 2001 Back to top What can Irradiation do At Low Doses: Delays ripening and sprouting in fruits and vegetables), and Controls insects and parasites (an alternative to chemicals and fumigation) At Medium Doses: Extends shelf-life, Reduces spoilage, and Reduces pathogenic organisms At High Doses: Sterilization of meat, poultry, seafood, prepared foods and Disinfection of spices Back to top Approved dosages for US Spices and dry vegetable seasoning, decontaminates and controls insects and microorganisms - 30 kGy Dry or dehydrated enzyme preparations, controls insects and microorganisms - 10 kGy All foods, controls insects - 1 kGy Fresh foods, delays maturation - 1 kGy Poultry, controls disease-causing microorganisms - 3 kGy Red meat (such as beef, lamb and pork) controls spoilage and disease-causing microorganisms - 4.5 kGy (fresh), 7 kGy (frozen) Back to top Irradiation Resources Irradiation cannot be used with all food because it can change their acceptability and palatability, usually those with high fat contents. For example, higher fat dairy products can have undesirable flavor changes. Some fruits such as peaches and nectarines, may have tissue softening. Oysters and other raw shellfish can be irradiated, but the shelf life and quality decreases because the live oyster inside the shell is damaged or killed by the irradiation. Currently in the United Sates, strawberries and other fruits in Florida are being irradiated. Tropical fruits from Hawaii's mainland are being irradiated as a replacement to the normal fumigation process. Beef, pork, poultry and many commercial spices are also being irradiated. Forty countries are permitting food irradiation, including: France, the Netherlands, Portugal, Israel, Thailand, Russia, China, and South Africa. The USDA estimates that the American consumer will receive approximately $2 in benefits such as reduced spoilage and less illness for each $1 spent on food irradiation. The Food and Drug Administration (FDA) requires that all food that has been irradiated carry the international symbol of the radura, and the statement "Treated with radiation" or "Treated by Irradiation" on the packaging. Back to top How Food Irradiation Works The short, high energy waves of radiant energy of the irradiation process transfers into the molecules of the microbe. This energy creates reactive chemicals that damage the cells DNA. This damage interferes with the cell replication and thus duplication and reproduction of the organism fails. Depending on the size of the organism, the amount of DNA, and how quickly the organism can repair itself, the sensitivity to the irradiation varies. Larger organisms, such as insects and parasites are easily eliminated with irradiation because they have a greater amount of DNA that can be affected and damaged. Smaller organisms, such as viruses, are more resistant. Irradiation is measured in units called “Grays” (GY). The killing effect of irradiation on microbes is measured in D-values. One D-value is the amount needed to kill 90 percent of that organism. Back to top Applications of Food Irradiation Food irradiation is applied to food products for different purposes, including: Controlling foodborne pathogens – Irradiation is currently used to eliminate pathogens that cause foodborne illnesses, but this process does not protect the food from being recontaminated, and consumers should handle the food in the same manner as non-irradiated products by being aware of storage and handling, refrigeration and cooking time and temperatures, and cross contamination. Preservation– Irradiation can destroy or inactivate the organisms that cause spoilage and decomposition, thereby extending the shelf-life of the food. There are some advantages to irradiation for the purpose of preservation. Unlike canning, the food does not undergo a lot of heat, so the food is much closer to its original fresh state. There is no additional liquid required and there is little loss of its own liquid since the temperature does not rise. Therefore the flavor, texture and color remain very much like the original food. Sterilization – As with canned and other heat sterilized foods, the product can be stored for years at room temperature. This is helpful with military and space flights. It also can be beneficial to immune-compromised patients, and hospitals. Controlling sprouting, ripening, and insect damage – Irradiation is an alternative to chemicals. It can be used with tropical fruits, potatoes, grains, etc. There is no residue left on the food. Back to top Regulators of Food Irradiation Food irradiation in the United States is primarily regulated by the FDA since it is considered a food additive. Other federal agencies that regulate aspects of food irradiation include: United States Department of Agriculture (USDA) - meat and poultry products Nuclear Regulatory Commision (NRC) - safety of the processing facility Department of Transportation (DOT) - safe transport of the radioactive sources Each new food is approved separately with a guideline specifying a maximum dosage. Packaging materials containing the food processed by irradiation must also undergo approval. Back to top Irradiation Technologies Currently three different technologies exist for the process of irradiating food products, including: The first technology: Use of radiation given off by a radioactive substance, such as Cobalt 60 or Cesuim 137. These particular substances give off photons that produce gamma rays. They do not release neutrons, thus the food does not become radioactive. The photons can penetrate up to several feet. This is the same technology that has been routinely used to sterilize dental and medical supplies. The photons are constantly released. When the substance is not in use, it is submerged in a pool of water that absorbs the photons safely and completely. Electron Beam technology: No radioactive substance is involved. Electrons are “shot from a gun” toward the substance. Shielding is needed to protect workers from the released electrons. This technology is limited since the electrons can only penetrate up to a little over an inch. The food must be very thin. X-Ray technology: This is the newest technology and is still being developed. A beam of electrons are directed onto a thin plate of gold or other metal producing a stream of X-rays much stronger than X-ray machines found in hospitals. Like the Cobalt technology, this technology can pass through thick foods, but like the electron beam technology requires protection for the users. A limited number of these machines have been built. Back to top Public Interest Food irradiation is currently encountering public opposition because many organizations feel there is a danger to the environment and consumer. These concerns include the potential that the food itself may become radioactive, loose its nutritional value, long term health risks associated with eating the processed food, and environmental risks at the processing facilities. There is controversy over the production of small amounts of substances called radiolytic products. There is debate over whether the levels produced are harmful and to what degree or risk is produced. There is no debate, however, that they are produced when food is irradiated. The public concern also looks ahead into the industry's use of irradiation as a fallback to sterilize "dirty" food. Currently, 40 countries and a large number of government agencies and medical organizations are advocates of food irradiation as a safe and effective method to reduce the risk of foodborne illness. As identified, research has provided results discounting many of these misconceptions. Ongoing research continues to identify and improve the effectiveness of the irradiation process with the use of other ingredients and established food processes to improve costs, palatability and safety. Agencies, such as the CDC, feel that consumer confidence will depend on making food clean first, and then the use of irradiation or pasteurization will make it safe. Food irradiation is a logical next step to reducing the burden of foodborne disease in the United States. Back to top Organizations Supporting Food Irradiation American Dietetic Association American Council on Science and Health American Feed Industry Association American Farm Bureau Federation American Health Association American Meat Institute American Medical Association American Veterinary Medical Association Apple Processors Association Chocolate Manufacturers Association Council for Agricultural Science and Technology Florida Fruit and Vegetable Association Food and Drug Administration Food Distributors International Grocery Manufacturers of America Health Physics Society International Atomic Energy Agency International Food Information Council Institute of Food Technologists Miller's National Federation National Cattleman's Beef Association National Confectioners' Association National Fisheries Institute National Food Processors Association National Meat Association National Pork Producers Council National Turkey Federation New England Journal of Medicine Produce Marketing Association United Egg Producers United Fresh Fruit and Vegetable Association United Nations Food and Agriculture United States Department of Agriculture U.S. Chamber of Commerce Western Growers Association World Health Organization Organizations Opposing Food Irradiation Center for Food Safety Sunshine Coast Environment Council Lenape Nation Organic Consumers Association Public Citizen Stop Food Irradiation Alliance Back to top Resources Food Irradiation: A Safe Measure (PDF) FDA with Contributions from: USDA, HHS, American Meat Institute Food Irradiation Information Iowa State University Extension Food Safety, Irradiation Center for Infectious Disease Research and Policy Frequently Asked Questions about Food Irradiation (pdf format) CDC/Minnesota Department of Agriculture, FDA, Minnesota Department of Health, and Minnesota Beef Council Get the Facts about Food Irradiation CDC/Georgia Beef Board Irradiation: A Safe Measure for Safer Food USDA & FDA Irradiation�An Overview of a Safe Alternative to Fumigation USDA/ARS Irradiation of Animal Feed (Talk Paper) FDA Irradiation of Meat and Meat Products Review of Risk Analysis Issues USDA/FSIS USDA Approves Irradiation of Meat to Help Improve Food Safety (News Release) USDA & FDA Back to top

This document was created by Kristina Brandriff. Users are encouraged to provide feedback and comments. This document was created in Jun 2003; Updated in Dec 2005