1. OBJECTIVES 1. Alternative method for food treatment;
FOOD IRRADIATION
OBJECTIVES
1. Alternative method for food treatment;
2. What is food irradiation?
3. Benefits and changes of foodstuffs.

2. FOOD IRRADIATION 1
1. Waves and energy

3. FOOD IRRADIATION 2
1. Energy - >10keV

4. FOOD IRRADIATION 3
2. Types of irradiation used in the food technology
2.1. Non-ionizing
- thermal
- microwaves
- UV light – stimulation of resveratrol production in grapes; microorganisms killing
UV treatment – might not remove all the microorganisms, especially those in the inner part of larger particles
UV treatment is applicable for disinfection of water, air, fruit juices etc.

5. What is Food Irradiation?
New commercial technology to eliminate disease-causing germs
Comparable to heat pasteurization
Used for decades in NASA space missions
already used for sterilization of:
medical devices, supplies and implants
wine corks and other food packaging materials
cosmetic ingredients
Single slide introduction to process

6. How Does Food Irradiation Help?
food is exposed to carefully controlled amounts of radiation
radiation damages DNA of microbes and parasites
disease-causing germs are reduced
bacteria which cause spoiling are reduced
sprouting is slowed or stopped

7. What are the Results of Food Irradiation?
When used in conjunction with proper food handling procedures:
food-borne diseases are reduced or eliminated
shelf-life is increased
the nutritional value of the food is preserved
the food does not become radioactive
dangerous substances do not appear in the foods

8. 2. Types of irradiation used in the food technology
FOOD IRRADIATION 5
2. Types of irradiation used in the food technology
2.2. Ionizing – allowed in more than 50 countries
1958, Stuttgart, Germany (the first commercially used irradiation – treatment of spices)
Approval
Food
Purpose
1963
Wheat flour
Control of mold
1964
White potatoes
Inhibit sprouting
1986
Pork
Kill Trichina parasites
Fruit and vegetables
Insect control Increase shelf life
Herbs and spices
Sterilization
FDA USDA
Poultry
Bacterial pathogen reduction
FDA USDA
Meat

9. FOOD IRRADIATION 6
2. Types of irradiation used in the food technology
2.2. Ionizing – concerns and regulations
1). safety
2). price – 3-5 millions $ (UHT equipment – millions $; equipment for chemical treatment of fruits – 1 million $)
3). consumers’ perception
4). in Europe – the most treated product are frogs' legs, chiken meat and dried herbs and spices
Radura – symbol of irradiated food

10. Facility Accidents and Waste
Severe accidents are not possible
electron beam and x-ray sources can be easily turned off
gamma ray sources cannot blow up
The facility itself cannot become radioactive
no radioactive waste
used Co-60 gamma sources can be recycled/regenerated

11. FOOD IRRADIATION 7
2. Types of irradiation used in the food technology
2.2. Ionizing – effect of irradiation
Type of food
Effect of Irradiation
Meat, poultry
Destroys pathogenic fish organisms, such as Salmonella, Campylobacter and Trichinae
Perishable foods
Delays spoilage; retards mold growth; reduces number of microorganisms
Grain, fruit
Controls insect vegetables, infestation dehydrated fruit, spices and seasonings
Onions, carrots, potatoes, garlic, ginger
Inhibits sprouting
Bananas, mangos,papayas, guavas, other non-citrus fruits
Delays ripening avocados, natural juices.
Reduces rehydration time
Some foods – undesirable: milk (flavor)
Peaches and nectarines – softening.

12. FOOD IRRADIATION 8
2. Types of irradiation used in the food technology
2.2. Ionizing – sources
γ – rays: cobalt-60, cesium-137
Х – rays: obtained when electrons beam hits surface of tantalum or tungsten metals.

13. FOOD IRRADIATION 9
2. Types of irradiation used in the food technology
2.2. Ionizing – devices
γ–rays – cobalt-60, cesium-137
Х–rays – obtained when electrons beam hits surface of tantalum or tungsten metals.

14. !
FOOD IRRADIATION 10
2. Types of irradiation used in the food technology
2.2. Ionizing – dosage and applications
Irradiation
Dosage, kGy
Products
Bellow 1 kGy (weak)
Inhibition of germination;
Decontamination;
Retardation of physiological processes;
Potatoes, onion, garlic;
Cereals, vegetables, fish;
Fresh vegetables and fruits
Between 1 to10 kGy (intermediate)
Prolonging the storage time;
Elimination of pathogenic microorganisms;
Improve of overall technological process;
Fish, strawberries;
Fresh and frozen sea products and meat (chicken);
Increase of grape juice, dehydration of vegetables
Between 10 to 50 kGy (strong)
Industrial sterilization;
Disposal of some unwanted substances.
30-50
10-50
Meat (birds, sea products), ready-to-cook food;
Spices and herbs
1 Gy (Gray) – 1 Joule radiation energy absorbed by 1 kg of matter

15. ! FOOD IRRADIATION 11 3. Changes of food components – carbohydrates
are generally stable

16. ! FOOD IRRADIATION 12 3. Changes of food components
Ionizing radiation – lead to
destruction of anthocyanins
(and some pigments)
Ionizing radiation – lead to
formation of new type of components
2-alkylcyclobutanones (2-ACBs).-
NUTRITION AND CANCER, 44(2),
188–191 !

17. Non-irradiated sample
FOOD IRRADIATION 13
3. Changes of food components
Amounts are for 2.2 pounds (1 kilogram) cooked chicken*
Vitamin
Non-irradiated sample
Irradiated sample
Vitamin A (IU)
2200
2450
Vitamin E (mg)
3.3
2.15
Thiamin (mg)
0.58
0.42
Riboflavin (mg)
2.10
2.25
Niacin (mg)
58.0
55.5
Vitamin B6 (mg)
1.22
1.35
Vitamin B12 (mg) 21 28
Pantothenic acid (mg) 13 17
Folic acid (mg)
0.23
0.18
*E. S. JOSEPHSON, M. H. THOMAS, W. K. CALHOUN. Nutritional Aspects of Food Irradiation: An Overview. Journal of Food Processing and Preservation. Volume 2, Issue 4, Date: September 1978, Pages:

18. FOOD IRRADIATION 14
More information: