Course:FNH200/Lessons/Lesson 10/Page 10.6
10.6 Irradiation Methods & Doses
Table 10.2 shows the absorbed doses required to achieve a variety of applications ranging from inhibition of sprouting to achieving commercial sterilization of a food commodity.
Table 10.2. Typical applications of ionizing energy for food preservation
Note: Includes examples that are not approved for use in Canada.
| Dose (kGy) | Purpose | Examples |
|---|---|---|
| < 1 | inhibit sprouting of vegetables
kill insects eggs, larvae slow ripening inactivate parasites |
potatoes
wheat bananas pork |
| 1 to 10 | eliminate disease causing bacteria (Salmonella, E.coli O157:H7) and parasites
decrease or eliminate spoilage causing microorganisms (eg. mould) |
chicken, ground beef, fruit and vegetables
fresh strawberries |
| 10 to 50 kGy | decontaminate food ingredients and additives
commercially sterilizes food |
enzymes and spices
sterilized hospital diets, foods for use on missions in outer space |
Radiation Pasteurization (radicidation, radurization) methods
Radicidation is defined as a process designed to kill or inhibit disease-causing microorganisms (such as vegetative bacteria, yeasts, parasites) in food. Absorbed doses are often below 10 kGy. Foods that have been treated with a radicidation dose of ionizing energy must still be stored under refrigeration since all spoilage-causing microorganisms would not have been killed.
Radurization, a form of radiation pasteurization, has as its objective the killing of the majority of spoilage-causing microorganisms and parasites so that storage life of the food can be extended during refrigerated storage. For example, treatment of fish to kill most of the spoilage-causing psychrotrophic bacteria would extend the storage life of the fish at refrigerated storage temperatures. Absorbed doses for radurization are below 10 kGy (often < 1 kGy).
Radiant Sterilization (radappertization) methods
Radappertization, equivalent to thermal commercial sterilization, involves treatment of food with an absorbed dose of ionizing energy such that disease-causing microorganisms and all spoilage-causing microorganisms capable of growing at the conditions of storage (e.g., at ambient temperatures) are inactivated. Absorbed doses of ionizing radiation are greater than (>) 10 kGy (usually 20, 30 kGy).
Note that in Canada, doses above 10 kGy are NOT permitted!