For the past several weeks, the subject of
irradiation has been raised by readers of this blog as a way to eliminate
the problem of E. coli O157:H7 once and for all.
There are pros and cons to irradiation and a possible way forward that
would allow for consensus acceptance of this potentially important food
safety technology by consumers and processors.
First some of the pros:
1. The U.S. Food and Drug
Administration has recognized the safety of food irradiation and USDA has
established a regulation
for meat and poultry products
2. If applied at pasteurization
doses, irradiation can eliminate E. coli O157:H7, Salmonella
and other pathogens from raw meat and poultry products.
3. The US Centers for Disease Control
and Prevention estimates that irradiating half of all ground beef, poultry,
pork and processed meats would reduce food poisoning by 1 million cases and
prevent 6000 serious illnesses and 350 deaths (Smith, JS. Pillai, S.
Irradiation and food safety. Food Technol. 2004; 24:5).
4. If meat products are treated under
vacuum or in a controlled atmosphere, irradiation can be applied with a
minimal impact on flavor.
5. Irradiation has a negligible
effect on vitamins and other nutrients.
6. The companies
that are marketing irradiated ground beef have encountered little consumer
Now some of the cons:
1. Irradiation is considered a food
additive and therefore, labeling requirements are rather burdensome.
Irradiated foods must prominently display the radura
symbol on the label.
are two types of food irradiation in common use – Gamma irradiation which
is based on exposure to a radioactive source (usually Cobalt-60) and
Electron Beam irradiation which is based on electrons that are formed from
wall plug electricity. Gamma irradiation has the advantage of better
penetration and more even treatment, but it is more controversial and less
accepted by consumers. Electron Beam irradiation is limited in application
because it can only treat products that are a few inches in thickness.
third type of irradiation involves X-Ray energy and combines the advantages
of Gamma and Electron Beam. However, the technology has not been developed
as a practical means of treating food.
3. Pasteurization doses for Salmonella
are fairly high and difficult to achieve without significant
adverse effects on product flavor and overall acceptance. Pasteurization
doses for E. coli O157:H7 are generally lower, but vary by
4. Most irradiated ground beef being
marketed today is not treated at pasteurization doses.
5. There is some evidence that E.
coli can develop some resistance to Electron Beam irradiation (Levanduski
and Jacznski, International Journal of Food Microbiology, Volume 121, Issue
3, 10 February, 2008, Pages 328-334).
6. Other less controversial interventions have been
developed and are in use that have partially obviated the need for
irradiation (i.e. High Hydrostatic Pressure).
Next week, I will present some ideas about how
irradiation could become better accepted by consumers and more attractive
to the food industry.
Are there some pros and cons that I missed? Please let me know.