Fun Facts About Food Irradiation

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Fun Facts About Food Irradiation

• A presentation of the

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Why do we preserve food?

• Protect people from microorganisms, parasites,
  and other pests
• Extend shelf-life, improve long-term quality
• Make desirable alterations to food properties

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History of Food Preservation
Oldest Methods - Drying - Fermenting -
Salting - Smoking
Newer Methods - Freezing - Canning -
Refrigeration - Preservatives - Pesticides
Newest Method Irradiation
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What is food irradiation?

• Treatment of foods by subjecting them to ionizing
  radiation
• Does not and cannot make foods radioactive

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Ionizing Radiation

• Radiation that has the ability to produce ions -
  electrically charged particles
• Examples alpha particle, beta particle, high
  energy electron, gamma ray, and x-ray

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Nonionizing Radiation

• Does not have sufficient energy to create ions -
  instead tends to excite molecules without
  removing electrons
• Examples visible light, television waves, radio
  waves, and microwaves

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Sources of Ionizing Radiation

• Power plants
• Fertilizers
• Smoke detectors
• Accelerators

• Cosmic Radiation (the sun)
• Medical procedures
• Radon and other terrestrial sources
• Nuclear weapons fallout

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Food Irradiator Sources

• Cobalt-60 and Cesium-137
• Emit gamma rays
• Sealed in container - never touches food
• Can be recycled
• Machine generated beta or x-rays
• Produces no waste outside of the machine used to
  produce the radiation

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Irradiation Processes

• Sterilization
• Pasteurization
• Disinfestation
• Sprout Inhibition
• Delay of Ripening
• Physical Improvements

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Irradiation Sterilization

• Very high dose used to kill all organisms
• Sterilization of 50 disposable medical
  instruments
• Food sterilization - NASA, military, transplant
  patients

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Irradiation Pasteurization

• Reduces remaining number of living organisms
• Prevent growth of mold
• Kill bacteria and parasites

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Irradiation Disinfestation

• Kills insects and parasites in grains and other
  stored foods
• Fewer chemical residues on fruits and vegetables
• Does not prevent against re-infestation

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Physical Improvements

• Inhibit sprouting of potatoes, onions, and garlic
• Delay of ripening for strawberries, mangoes,
  bananas, tomatoes, etc.
• Incidental improvement in fruit texture and meat
  color

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How does irradiation do so many different things?

• High doses damage or kills cells
• Kills microorganisms or insects
• Lower doses alter chemical reactions and
  interfere with cell division
• Delay fruit ripening
• Prevent sprouting or parasite reproduction

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Are irradiated foods safe to eat?

• Foods cannot become radioactive at energies used
  in irradiation
• Below 10 kGy there are no known toxicological,
  microbiological, or nutritional problems

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Foods Approved for Irradiation in the United
States

• Fresh fruits and vegetables
• Herbs and spices
• Pork
• Potatoes
• Poultry

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Important Terminology

• Ion Atom that has been made electrically charged
  by the removal or one or more electron.
• Gray Unit of energy absorbed by a material. 1000
  Gy 1 kGy
• Radura Official symbol or logo indicating that
  food has been irradiated.

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Sources of Additional Information

• American Council on Science and Health
• http//www.acsh.org/food/index.html
• World Health Organization
• Safety and Nutritional Adequacy of Irradiated
  Foods
• Institute of Food Technologists
• Radiation Preservation of Foods