Script: Food Irradiation - Part I
Welcome to USDAís Food Safety and Inspection Service podcast. Each episode
will bring you cutting edge news and information about how FSIS is working to ensure public
health protection through food safety. While weíre on the job, you can rest assured that
your meat, poultry, and processed egg products are safe, wholesome, properly labeled,
and packaged correctly. So turn up your volume and listen in.
Hello and welcome. Iím Sheila Johnson with FSIS.
Joining me in the studio is Mary Porretta, a program
analyst from the Office of Policy and Program
Mary has been with FSIS for almost 13 years. Her duties
involve the analysis and the development of Agency
regulations and other policy documents including FSIS
Notices and Directives.
Iím sure many of you have heard about the use of
irradiation on food products and wondered how the
process works. Mary is going to explain it for us in
this first of a two- part series. The second podcast
will focus on regulation of the irradiation process.
Hi, Mary, and thanks for coming by.
Thanks, Sheila. Iím glad to be here.
Okay, letís get started. When we talk about irradiation
of food products, what exactly are we talking about?
Irradiation simply means exposing food to high levels of
radiant energy. Radiant energy includes microwave
and infrared radiation, visible light or ultraviolet
light, and ionizing radiation.
So when I microwave my burrito, Iím irradiating it?
Yes. Although, when weíre talking about the commercial
irradiation of food products weíre usually referring to
And what is ionizing radiation?
The key thing to remember is that treating meat and
poultry with ionizing radiation simply means exposing
the products to gamma rays, electron beams, or x-rays.
This is what we are referring to when we talk about the
irradiation of food products.
And why do we want to irradiate food products?
To help improve food safety and potentially extend their
Irradiation reduces the number of harmful microorganisms
that may be present in food, including Salmonella,
coli O157:H7, Staphylococcus aureus, Listeria
monocytogenes, Campylobacter jejuni, and the protozoan
parasite, Toxoplasma gondi.
However, like any antimicrobial intervention,
irradiation is not a substitute for good sanitation and
process control in meat and poultry plants.
It does no good to allow food to become contaminated
uncontrollably before the irradiation process because
these unsanitary conditions contribute to the potential
introduction of harmful organisms, as well as spoilage
Therefore, irradiated food should be handled and
processed using the same care as non-irradiated product.
Of the types of foods that FSIS regulates, which ones
are approved for irradiation?
The Food and Drug Administration (FDA), an agency under
the U.S. Department of Health and Human Services,
actually is responsible for approving what radiation can
be used for. FDA has found the irradiation of food to be
safe and has approved the sources and amounts of energy
that may be used.
Currently in the United States, irradiation is approved
for use on a variety of FSIS-regulated products
including refrigerated or frozen uncooked meat, meat
by-products, fresh poultry including whole or cut up
birds, skinless poultry, pork chops, roasts, stew meat,
liver, hamburgers, ground meat, and ground poultry.
What other effects does irradiation have on the food
Very little. Scientific studies of the sources and
amounts of irradiation approved by the FDA have shown
that the texture, flavor, and nutritional content of food
products are not significantly changed when compared to cooked food
Of the nutrients that are affected, the B-vitamins are
impacted the most. The likelihood of suffering from
vitamin deficiency is low because B-vitamins are readily
available in a varied diet.
Okay, back to what you said about irradiation reducing
the numbers of bacteria in food. Can you tell us a
little bit about how thatís accomplished?
Sure. Irradiation penetrates into food, killing insects,
pests and microorganisms without raising the temperature
of the food significantly.
It kills because the energy from the gamma rays,
electron beams, or x-rays damage the organismís DNA.
If the damage canít be repaired, the organism dies when
it grows or tries to duplicate itself. The DNA usually
canít be repaired, so itís a pretty effective method of
reducing the number of pests and microorganisms in food.
Cooking product also damages the organismís DNA in a
Interesting. Is it effective against all microorganisms?
Now thatís a good question. The answer is no. Since
irradiation works by damaging DNA, the size of the DNA
plays a very big part in determining the microbeís
Irradiation works well to eliminate parasites and
bacteria from food, but it will not work nearly as
effectively to eliminate viruses or prions from food.
Viruses have very small amounts of DNA and are less
sensitive to irradiation. And then there are prions,
such as those believed to be responsible for bovine
spongiform encephalopathy, or BSE, that have no DNA and
would not be affected.
Likewise, cooking also has a limited impact on viruses
Would you recommend irradiation as an antimicrobial
intervention that our listeners should consider?
We think plants should consider irradiation. It does
work well for eliminating bacteria and pests. And as
weíve said, texture, flavor, and nutritional content of
food products are not significantly changed when
compared to cooked food products.
Itís a plus when used properly, but only the plant
owners or operators can make the decision on whether
irradiation is the right intervention for their
operation, after careful research and consideration.
Of course. Mary, I want to thank you for being with us
today and giving us some good information about the
process of irradiation.
Itís been a pleasure!
And to our listeners out there, check out the FSIS Web
www.fsis.usda.gov for more podcasts. Be sure
to stay tuned for part 2 in this series on irradiation.
If you have any questions or wish to receive more
information, feel free to contact the Small Plant Help
Desk at (877) 374-7435. Thanks for listening!
Well, thatís all for this episode. Weíd like your feedback on our podcast. Or if you
have ideas for future podcasts, send us an e-mail at
email@example.com. To learn more about food safety, try our web site at
www.fsis.usda.gov. Thanks for tuning
Last Modified: April 14, 2010