Preservation of Food by Radiation
Published on: Mar 4, 2016
Transcripts - Preservation of Food by Radiation
PRESERVATION OF FOOD BY
MSc- 1 BIOCHEMISTRY
INSTITUTE OF SCIENCE
Causes of food spoilage
WHAT IS IRRADIATION
Exposing food to gamma rays,
x-rays or electrons to improve
shelf life and safety.
Irradiation breaks chemical
bonds killing microorganisms,
Key advantage: no heat
RADIATIONS USED IN
Application of Radiation
Most widely used techniques
of irradiating food are gamma
radiation from CO60 and Cs
Electron beams from linear
Radappertization : used in
canning industry , 30-40 kGy.
pasteurization of milk,2.5-10kGy.
* kGy (kilogray) One Gy is equivalent to energy of 1 joule absorbed by one
kilogram of food; 1000 Gy = 1 kilogray kGy. 0.005 kGy dose is sufficient
to kill humans. (Another unit of absorbed radiation dose is the rad.
One Gy = 100 rad.)
Effects on Food Quality
Proteins: aromatic amino acids
Lipids: production of carbonyls ,
organoleptic effect : rancidity.
Degradation of structural
polysaccharides : pectin and
Partial destruction of
Example: may produce
It does not inactivate dangerous toxins which
have already been produced by bacteria prior to
irradiation. In some cases, such as C. botulism, it
is the toxin produced by the bacteria, rather than
the bacteria itself, which poses the health
It does not prevent the aging of the fruit and
vegetables that can lower their nutritional value,
taste and flavors.
Irradiation also unavoidably kills off bacteria
that produce the smells that warn you when food
is going "bad."
Extensive scientific research
reviewed by the World Health
Organization (WHO) and the U.S.
Food and Drug Administration has
indicated that irradiated food is
safe to eat (WHO, 1994; U.S.
Department of Health and Human
What Foods Have Been Approved for Irradiation?
FDA has approved a variety of foods for
irradiation in the United States including:
Beef and Pork
Shellfish(e.g., oysters, clams, mussels, and
Fresh Fruits and Vegetables
Lettuce and Spinach
Spices and Seasonings
Effects of gamma radiation on the
nutritional and antioxidant
parameters of chestnuts.
Control of Listeria monocytogenes
on frankfurters and cooked pork
chops by irradiation combined with
modified atmosphere packaging.
James M.Jay,1996, Modern food
microbiology, Wayne state
food safety, Food
irradiation,1986,Dep.of Food Science
and Human nutrition,Michigan state
Issues in Food safety,United States
dept of agriculture, economic
research service, agriculture
information, Bulletin No.757/Aug 2000
Antonio AL, Carocho M, Bento A, Quintana B,
Luisa Botelho M, Ferreira IC,Effects of gamma
radiation on the biological, physico-chemical,
nutritional and antioxidant parameters of
chestnuts, Food Chem Toxicol. 2012
Sep;50(9):3234-42. Epub 2012 Jun
Kudra LL, Sebranek JG, Dickson JS, Larson
EM, Mendonca AF, Prusa KJ, Cordray JC,
Jackson-Davis A, Lu Z. Control of Listeria
monocytogenes on frankfurters and cooked
pork chops by irradiation combined with
modified atmosphere packaging. J Food Prot.
Radiation, Food and Water, Google Image
U.S Environmental Protection Agency,
FDA(Food and Drug Administration)