Irradiation Can Protect Foods From E. Coli, Other Bacteria, UM-Rolla Professor Says

Many kinds of foods don't stay fresh-looking for very long after they havebeen brought home from the supermarket, and some of those foods can evenmake you sick. "Millions of people get sick every year due to foodcontamination, and some die as a result," says Dr. Gary E. Mueller, anassociate professor of nuclear engineering at UMR.

According to some scientific sources, about 30 million people in the UnitedStates alone get food poisoning each year, and about 7,000 of those peopledie.

The most recent food poisoning scare was the recalling of hamburger meatcontaminated with the E. coli bacteria, Mueller says.

"Cooking that contaminated hamburger properly would have killed the E.colibacteria," Mueller says, but a safer and better approach to keeping foodsfree of contaminants is irradiation.

Irradiation -- a practice approved in many countries including the UnitedStates -- keeps meats, fresh fruits and vegetables fresher andcontamination-free for months instead of just days, says Mueller.

"A giant step toward a solution to the problem is to irradiate the food inthe processing before it is shipped to the market," he says.

"First, the shelf life of the food can be extended because irradiationkills spoilage organisms and slows down the natural ripening processes,"Mueller says. "Secondly, the process reduces food-borne illnesses by reducing oreliminating pathogens, such as E. coli. And thirdly, the process is safe,cost effective, highly successful, and government-regulated by thosecountries now using the method."

The food irradiation process consists of taking foods such as potatoes,spices, fresh fruits, red meats, dried vegetables, fish and poultry andirradiating it with gamma rays from a radioactive source.

Some food shoppers are wary of buying and eating what they think might beradioactive. "One of the misconceptions is that when you irradiate foodsthey become radioactive, but that is not the case," Mueller says.

Another concern is that irradiation of food will ruin its taste andnutritional value. But extensive research by the World Health Organization,the Joint Expert Committee of the Food and Agriculture Organization, andthe International Atomic Energy Agency has shown that below a certainradiation dosage, foods are not affected and the taste and nutritionalvalue is not changed, Mueller says.

"The Food and Drug Administration in the United States has approved theradiation of foods since the 1960s but the practice is not yet used inlarge degrees," Mueller says. "Canada has been using the method for 40years and 40 other countries now irradiate over 50 food commodities."

Just how long can food last after being irradiated? Mueller says that porkloins that have been irradiated and stored at refrigeration temperaturestakes about 90 days to spoil as compared to 40 days for that of treatedpork. "And the life expectancy of fresh fruits can be increased from a weekto a month. Strawberries, for instance, can be extended from a few days upto four weeks," he says.

But are people willing to buy irradiated foods? Mueller believes that theyare.

"Hawaii shipped processed papayas to California but before shipment some ofthe papayas were given a hot water treatment, which killed the bacteria and fruit flies," he says. The other papayas were irradiated, which alsokilled bacteria and fruit flies. "After those papayas were stocked inCalifornia markets consumers bought 10 irradiated papayas for every 11sold," Mueller says.

"The process is safe and it works and people are convinced of that,"Mueller says. "Now we have to convince the food industry. And the UnitedStates has to embrace this technology that other countries are nowsuccessfully using."