1. ITM UNIVERSITY GWALIOR
DEPARTMENT OF FOOD TECHNOLOGY
under the guidanceof
MS NIHARIKA THAKUR PRESENTED BY
Asst professor SOUMEE MANDAL
MSc FOOD TECH Ist SEM
2. What is food irradiation?
Food irradiation is a form of food processing with a
limited number of kinds of radiant energy put together
as ‘ionizing radiation’ ,that extends shelf life and
reduces spoilage of food. Foods such as fruits,
vegetables, spices and meats can be exposed
to radiation to kill insects, moulds and micro-
organisms.
It is used as a preservation method
3. History of food irradiation
• US Army investigates use of irradiation to improve safety
and quality of troop diets in 1930
• Approved for potatoes by Canada in 1960
• 1963 First FDA approval for insect control in wheat flour
• 1983 FDA approved irradiation for controlling microbes
in spices
• 1985 FDA allowed uses of irradiation to strawberries
,poultry, beef & pork
4. Sources of radiation
Electron irradiation- e¯ are accelerated close to the
velocity of light, have higher cross section thus do not
penetrate the substance more than few inches. Eg-
beta particles.
X-ray irradiators are scalable and have good
penetration, with the added benefit of using an
electronic source that stops radiating when switched
off. X rays are photon radiation of high energy
spectrum.
5. Food irradiation using Cobalt-60 is the preferred
method by most processors, because the better
penetration enables administering treatment to entire
industrial pallets or totes, reducing the need for
material handling.
The radiation is obtained through the use of
radioisotopes, generally Cobalt-60 or, in theory,
Cesium-137. Cesium-137 is recovered during the
refinement of spent nuclear fuel.
6. Effects
Direct
Hits a specific target like
bullet
Changes in color and
texture by direct
collision
Not sufficient for
explaining radiations
effects.
Hits mainly microbes
and enzymes
Indirect
High energy radiations
hit water molecules
instead
Formation of reactive
hydrogen and hydroxyl
ions
Oxidizing radicals alter
the molecular structure
Hits constituents in
aqueous solution
7. applications
This method of preservation prevents growth of food
poisoning bacteria, destroys parasite, and delays
ripening of fruits and vegetables.
Further applications include sprout inhibition, delay
of ripening, increase of juice yield, and improvement
of re-hydration.
Sterilization induces prolonged shelf life, can be used
for hospitals, military and space flights. It also controls
food borne illness.
8. advantages
Little or no heating of food
Can treat packaged or frozen foods
No chemicals used for preservation of fresh foods
Low energy requirements
Comparable change in nutritional value
High automation
9. Disadvantages
gamma radiation cant be turned off/on, workers need
to be protected.
High capital costs
Possible development of resistant microbes.
Inadequate analytical procedures to detect irradiation
in food
high radiation can result in radical ion formation .
10. Unit of radiation
Electron volts = 1.6 * 10^ -19 joules, so 32.5 eV is
required to produce 1 ion pair in air.
Rad = 10 ^-6 joules absorbed/ gram of material
1 kGy = 100,000 rads
1 roentgen= 2.08 * 10^9 ions/ cm^3 of dry air under
standard temp and pressure.
11. RADURA SYMBOL
The symbol Radura was originally used as a symbol of
quality for food processed by ionizing radiation.
The central dot is the radiation source. - The two circle
segments ('leaves') are the biological shield to protect
the workers and the environment. - The outer ring is
the transport system, the lower half of it is shielded
from radiation by the biological shield and resembles
also the loading area, the upper broken half
symbolizes the rays hitting the target goods on the
transport system
12. ENDORSMENT
The wholesomeness and nutritional adequacy of
irradiated food has been well established. It is
approved by the international and national regulatory
authorities including USFDA, FSANZ and FSSAI
(PFA). Several reputed professional bodies including
American Medical Association, Institute of Food
Technologists, and American Nuclear Society have
endorsed the utility, safety and benefits of radiation
processing of food
13. Irradiation in India
In India radiation processing of food can be
undertaken both for export and domestic markets. For
export, food could be processed for shelf-life
extension,and hygienization,. Recently, it has been
possible to export famous Indian mango to USA using
this technology.
Huge quantities of cereals, pulses, their products,
fruits and vegetables, sea foods, and spices are
procured, stored, and distributed throughout the
length and breadth of the country. Radiation
processing can be used for disinfestation and storage
of bulk and consumer packed commodities for supply
chain management and retail distribution.
