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Texas
Agriculture Archive
November 21, 2003
Texas A&M:
The safest burgers you'll ever eat!
COLLEGE STATION — Hamburger patties, already packaged for retail and boxed in brown cardboard cartons, travel up a conveyor belt inside a high-tech, research facility at Texas A&M University. The cartons travel to a windowless, concrete room, where they are zapped with an invisible beam carrying 10 million electron volts of energy.
The burgers aren't cooked—they have just been irradiated, making them the safest burgers you'll ever eat.
Texas A&M scientists are convinced that what's being done today to common hamburger is just the beginning of a coming revolution in food safety.
Researchers at the Institute of Food Science and Engineering at Texas A&M are involved in one of the most promising food safety technologies of the 21st century—food irradiation with electron beam technology. The university's Electron Beam Food Research Facility is the result of a $10 million cooperative research agreement between Texas A&M and the SureBeam Corporation. The commercial-scale research facility uses SureBeam's patented electron beam and X-ray technology to develop safe and efficient protocols for killing pathogens and pests in beef, poultry, fruits and vegetables.
This private/public partnership gives Texas A&M a state-of-the-art facility unavailable at any other university in the world.
"It is a great illustration of a well-defined research partnership where both partners gain tremendously," says Dr. Mark McLellan, the institute's director. "What we did is take the 24-hour clock and split it in half. SureBeam conducts its test market and commercial processing research during half the clock and A&M conducts its research during the other half, ensuring that the place remains a research facility and not a fully commercial operation."
The facility's doors are open to other scientists, and research results can be 100 percent transferable to commercial applications. In July, the USDA designated the institute a National Center for Electron Beam Food Research.
In operation since October 2002, the Electron Beam facility is attracting research projects covering a wide range of food safety issues, such as water quality and detoxification, food additives, food toxicology, and quarantine problems.
Approved by the Food and Drug Administration, irradiation destroys insect pests and such pathogens as E. coli 0157, Salmonella, Campylobacter, and Listeria. The American Medical Association, the Centers for Disease Control, and the World Health Organization (WHO) endorse the safety of irradiated foods. Forty-two countries have issued approval for food irradiation technology in more than 240 foods.
Irradiation is called a cold pasteurization process, and the food, in most cases, is exposed for only parts of a second without raising the temperature more than one-and-a-half degrees. The appearance, taste and texture of the food remain largely unaffected, and nutrient losses are less than those caused by cooking. McLellan says reviews by the WHO show that food irradiation is no more hazardous than canning, drying, heat pasteurization, or deep freezing.
Irradiation used to be done with radioactive materials, but that's a technology that's quickly being superseded.
"Not many food companies wanted an active radioisotope in their facility 24 hours a day because of safety and biosecurity issues," explains Dr. Andy Vestal, associate director of outreach for the institute.
The institute's electron beam (or E-beam) linear accelerator uses electricity rather than isotope technology to generate energy, and it can be switched on and off like any other electrical appliance.
In fact, the E-beam works the same as another electron beam accelerator found in most homes—the television set.
"The back of the television picture tube fires electrons at a high speed toward the screen," explains Doug Johnson, the facility's general manager.
"The electrons hit the red, green and blue dots on the screen to make the picture; the screen's half-inch plastic cover shields you from the electrons. Their speed determines how deeply the electrons will penetrate. In a television, each electron has 24,000 electron volts of energy; our machines have 10 million electron volts of energy and will penetrate about three or four inches in ground beef. That's why you can't sterilize a bologna sandwich with your television," he adds.
How do electrons destroy harmful pathogens?
"A stream of energy-releasing electrons is accelerated to 99.9 percent the speed of light using radio frequency or microwaves," Vestal explains. "These electrons collide with the DNA of a pathogen such as E. coli. This damages or destroys the DNA bonds so that the organism can no longer reproduce or is killed outright."
"The more complex the organism, the more its DNA is susceptible to irradiation, so the lower the dose can be," Johnson says. "An insect has more DNA and would require less radiation than a bacterium, and a bacterium less than a spore or virus."
The institute's E-beam facility has three linear accelerators. Two of them use electron beams. Since electron beams can penetrate only a few inches, the third accelerator creates X-rays for deeper penetration of thicker objects, such as a turkey or roast, or larger packages of food.
Long before commercial food is shipped to the facility, Johnson and his staff have painstakingly calibrated the radiation energy dosage or kilograys according to the type of food and the dimensions of the packaging. Within the E-beam chamber, each package is scanned with electrons. The accelerators produce a constant level of energy, and the speed of the conveyor belt carrying the packages controls the exposure time.
These packages are not sterile. Like pasteurized milk, the targeted pathogens are killed, but the food products still have a limited shelf life. Johnson is quick to point out that the food could still become contaminated if the packages are opened and the food mishandled.
It's a myth that irradiation makes up for careless or unsanitary practices in food processing facilities.
Meat and poultry products are inspected and must meet USDA safety standards before leaving the processing plant. Irradiation cannot reverse spoilage to make "bad" food "good" again.
Irradiated foods are gaining acceptance. Since the FDA approved the distribution of irradiated ground beef in 2000, more than 6,000 retail outlets have offered it. According to Vestal, irradiated food began showing up in some grocery chains and restaurants in the Midwest and is slowly spreading across the country. Home-food delivery companies, such as Omaha Steaks and Schwan's, now offer irradiated products nationwide. Although not yet widely available in the Lone Star State, Vestal says Texas may see growth in the next six months.
Consumers can easily identify irradiated foods. The FDA requires that packaging be labeled with the "radura," an international symbol for irradiation, plus labeling stating that the food has been treated with irradiation.
Vestal points out that consumers still have a choice.
"When this product goes into a grocery store, it's alongside the non-irradiated product. The irradiated ground beef generally costs anywhere from 10 cents to 30 cents a pound more."
Dairy Queen, one of the first fast-food restaurants to introduce irradiated burgers, began offering them in 2002 after research from SureBeam showed that irradiation reduced bacteria in patties.
"We want to serve the safest product—one more level of food safety," says Dean Peters, spokesperson for American Dairy Queen Corporation.
During 60-day test periods at two stores in Minnesota, Dairy Queen provided customers with educational materials, surveyed customer feedback, and monitored sales. Results were so favorable that Dairy Queen expanded its test market and serves irradiated burgers in more than 100 stores in Minnesota, South Dakota and Wisconsin. Peters says the company plans to make irradiated burgers available in the Northeast and Southwest.
"Once consumers are educated [about irradiation] there is a high level of acceptance," Peters notes. In fact, some customers said they will buy the Dairy Queen burgers because they are irradiated, and half of those surveyed said they would pay 5 to 10 cents more for an irradiated burger. Peters estimates that the irradiated burgers cost only 1.2 cents more per patty.
Besides the proven food safety applications, fear of litigation is another driving force behind the upsurge in irradiation by food companies.
"When you have a major outbreak and someone becomes ill or dies, the question that is asked—and generally in front of a jury—is did you act in all best faith to deliver the safest possible product?" McLellan says.
McLellan predicts that as people become more aware of the benefits of irradiation and products become more widely available, consumers may view irradiated foods as commonplace and expected.
To learn more about the Texas A&M Electron Beam Food
Research Facility go to http://ifse.tamu.edu/E-beam; for further information
about SureBeam's technology, http://www.surebeam.com.
