Transcript No Slide Title

FOOD IRRADIATION
Maria del Pilar Solano, M.D.
April 29, 2003
What is Food Irradiation ?
“Process by which food is exposed to a
controlled source of ionizing radiation to
prolong shelf life, improve microbiologic
safety, and/or reduce the use of chemical
fumigants and additives”
Food Irradiation Uses
• Reduce insect infestation -grain, spices, fruits
and vegetables
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Inhibit sprouting -tubers and bulbs
Retard ripening -fruits
Inactivate parasites -meats and fish
Eliminate spoilage microbes -fruits, veggies
Extend shelf life -poultry, meat, fish, shellfish
Decontaminate -poultry and meat
Sterilize foods and feeds
FOOD-BORNE ILLNESS
Listeria
Toxoplasma
Hepatitis A
Salmonella
Criptosporidium
E.coli. Shiguella
Emer Inf Dis 1999;5: 786
Irradiation Sources:
•Gamma rays (cobalt 60 or Cesium 137)
•Electron-beam
•X ray
Dose for food irradiation: 0.05-10 kGy
Food Irradiation-Regulation
• 1958: Food Additives Amendment to the
Federal Food, Drug and Cosmetic Act of
1938
Food
Dose (KGy)
Purpose
Approval year
Wheat flour
0.2-0.5
Control of mold
1963
White potatoes
0.05-0.15
Inhibit sprouting
1964
Pork
0.3-1.0
Kill Trichina parasites
1986
1.0
Insect control, increase shelflife
1986
Herbs and spices
30
Sterilization
1986
Poultry
3.0
Bacterial pathogen reduction
1990-FDA
Poultry
1.5-3.0
Bacterial pathogen reduction
1992-USDA
Meat
4.5
7(frozen)
Bacterial pathogen reduction
1997-FDA
Meat
4.5
Bacterial pathogen reduction
1999-USDA
Fresh shell eggs
3.0
Control Salmonella species
2000
Fruit
vegetables
and
(fresh)-
Food Irradiation - Safety
• Radiologic and toxicologic safety:
- Neither the food nor the packaging become
radioactive
- No concern for unique radiolytic products (FDA)
- Animal feeding studies since 1950 with metabolic,
reproductive, teratogenic, mutageic endpoints.
FAO, WHO, FDA food irradiation is safe under
specified conditions
Food Irradiation-Safety
• Microbiological Safety
Microbiologic safety
• Viruses, spores, prions are resistant to
radiation
• Gram(-)spoilage bacteria > suceptible than
pathogenic bacteria
• Clostridium botulinun type E is resistant
• ? Increase in mycotoxin after irradiation
• ? Radiation resistance and mutational
changes
Nutritional Adequacy
• Changes similar to those of cooking,
canning, pausteurizing, heat processing
• Vitamin loss: Thiamine>Vit C,
B6>B2>niacin. Synergism with heat
• CHO and proteins relatively irradiationresistant
• Fats can be oxidized rancidity, odor
changes
Consumer Issues
Controversies
• Safety: ?Chromosome damage in
susceptible individuals. ?long-term effects
• Nutrition: ? Effect of Vitamin loss in
elderly, malnourished and children
• Environmental: ?danger of transporting
radioactive isotopes, new irradiation plants,
worker exposure
The Future ?