Wouldn’t it be wonderful to wave a magic wand over the food supply and make it safe to eat? Since that’s not possible, we can do the next best thing: food irradiation. Exposure of foods to X-rays and other forms of ionizing radiation kills the molds, bacteria, and insects that cause spoilage. It delays the ripening of fruits and berries, so extends shelf life. In addition, that they fresh longer. Previously, heat and the use of chemicals (formaldehyde, alcohol, or various pesticides, were the major methods of sterilization, but each had its drawbacks. Heat sterilization entails cooking foods, so they are no longer fresh; chemical that kill bacteria and other microorganisms often make foods inedible. Irradiation would seem to be an ideal means of sterilization, but the public has been slow to accept it.
Radioactive foods?
Despite assurances that irradiation with X-rays or certain isotopes does not make food radioactive, some consumer and environmental groups remain unconvinced. The worry that any radiation exposure poses a potential environmental hazard, even if the food themselves are not made radioactive. They also fear radiation may foster the development of dangerous mutant organisms or “unique radiolytic product”. The latter refer to compound such as 2-alkylcyclobutanones, which form when animal fat is irradiated. some studies have shown that some compound can cause strand breaks in DNA, which raises the prospect of cancer. Most researchers, however, do not attach much importance to this finding. As in cooking, the benefits of irradiation greatly outweigh the risks. There are roughly 50 million cases of food borne illness in North America every year and a large number of these are causes by E. coli and salmonella, which could be controlled by irradiation. Food such as wheat, flour, potatoes, and spices have been irradiated in many countries for decades without any link to harmful effects.
The government mandates that only certain forms of irradiation can be applied to foods to ensure that they don’t absorb the radioactive material. X-rays, which pass through an object without living behind radioactive material, and exposure to certain cobalt an cesium isotopes are all acceptable methods. These methods of cold sterilization allow most irradiated foods to retain their fresh appearance and taste. When meat, fish, and seafood are exposed to high doses of radiation needed to destroy parasites, salmonella bacteria, and other organisms, however, the flesh of some meat may darken, and fish and seafood may become mushy. Irradiation can also oxidize the fats in whole grains, causing them to taste rancid.
Beneficial Effects
In general, irradiation preserves more nutrients – particularly niacin, riboflavin, thiamine, and other B-group vitamins – than other sterilization methods do. But very high radiation doses, such as those needed to sterilize meat, will destroy some of the fat-soluble vitamins A, E and K. The effects of irradiation on vitamin C remain unknown; some studies show no loss of this nutrient, while others indicate major losses.
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Irradiated foods must bear this international symbol
Advocates of irradiation emphasize that the technique can increase food supplies in many underdeveloped parts of the world, especially in the tropics, where food spoilage destroys much of the food produced. Irradiation could conceivably solve chronic food shortages in these areas.
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Food For Thought
Irradiation helps to protect people with compromised immune systems
Food irradiation adds an extra measure of food safety for AIDS patients and other with lowered immunity; these people are cautioned not to eat uncooked fruits and vegetables and to make sure that all meat, fish, eggs, and other food that may harbor disease-causing bacteria or parasites are cooked until well done. Even after these precautions are taken, food-borne disease are a major hazard for people with compromised immunity. High dose irradiation can eliminate these dangers.
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