Although not yet extensively used in the meat industry, experts predict irradiation will become a more common practice in the future.
There is a technology available that can significantly reduce foodborne pathogens in ground beef and poultry. It is a technology endorsed by virtually every government organization in the U.S., including the Centers for Disease Control (CDC), the U.S. Department of Agriculture (USDA), the American Medical Association and the World Health Organization.
Yet, this technology — irradiation — has gotten nothing but a bad rap in the past due to consumer concerns over the process, specifically the possibility of long-term health risks of the radiation used to eliminate the pathogens. But the process has been studied for nearly half a century now and found to be safe and risk-free, and the public finally is warming up to the use of irradiation on food products. In fact, a recent CNN poll reported that 70 percent of consumers said they think it is safe to eat meat that has been irradiated to kill harmful bacteria.
“When adequately educated, consumers will accept irradiated meat,” says Ron Eustice, executive director of the Minnesota Beef Council, which has been educating consumers about irradiation for the past 10 years. One of the biggest reasons for acceptance is the focus on food safety and increased publicity of information regarding foodborne illness. A study conducted by the USDA Economic Research Service and the University of Florida found that consumers are willing to pay more for a safer food product. The CDC estimates that food irradiation on a large-scale basis will prevent nearly 900,000 cases of illness, 8,500 hospitalizations, over 6,000 catastrophic illnesses and 350 deaths each year in the U.S.
So what’s the holdup in instituting irradiation on a large scale? The biggest issue is the limited number of irradiation facilities in the U.S. There are only two major irradiation providers in this country — Sadex Corp. in Sioux City, Iowa, and Food Technology Service in Mulberry, Fla. Companies seeking to irradiate large amounts of product must have it shipped to one of these facilities, which can be challenging for processors not located in the vicinity. This has been made even more difficult due to the current high fuel and transportation costs.
Handling costs are another hurdle when factoring in irradiation. “The cost situation depends on the amount of handling it takes to process the product,” says Harlan E. Clemmons, president and COO of Sadex Corp. “The dose of irradiation also is a factor in establishing a price. In addition, there is a cost involved for refrigeration.” He estimates the price to treat a product is anywhere from 7 to 15 cents per pound.
Still, even though irradiated food adds a few cents per pound to the cost of production, the products’ extended shelf life can potentially offset at least some of these costs. Irradiated product has a shelf life two to three times greater than non-irradiated product. For example, irradiated ground beef can be out 45 to 60 days, pork up to 140 days depending on the cut, and poultry out up to 21 days.
Important to note that irradiation does not eliminate the possibility of cross-contamination of meat. This is because, while irradiation virtually eliminates harmful bacteria, the food is not sterile. Because common spoilage bacteria are still present, proper handling and storage procedures are necessary.
Even though rare hamburgers are safer from E. coli, people who may be at higher risk for foodborne illness, such as young children, the elderly and those with compromised immune systems, should still only eat fully cooked ground beef.
In addition, all irradiated foods must contain an identifying symbol called a “radura.” Foods that contain irradiated spices or foods served in restaurants do not have to be identified as being irradiated. Congress’ Farm Bill allows companies to label irradiated food as pasteurized in addition to irradiated.
The three irradiation technologies used today are electron beams, gamma rays and X-rays. The majority of irradiated meat is processed using either E beam or gamma ray technology.
Electron beams, also called E beams, are streams of fast-moving electrons, produced in electron accelerators. Electrons from approved accelerator sources can penetrate food to a depth of only 1.5 inches. Two opposing beams can treat a little more than twice that thickness. Shipping cartons of food products are generally too thick to be processed with this method.
Sadex Corp. uses E beam irradiation technology. According to Clemmons, the advantages of E beams are speed, efficiency and total use of electricity. “The down side is that, to process quickly, the product has to be configured uniformly,” he says.
Product that is not ideally packaged for this application needs to have something else to absorb part of the E beam. “A box of beef that is 3.5 inches thick can be processed more efficiently than a small box of burgers that has multiple layers. Some companies have a square patty layout to alleviate air space in the box for better processing. It is easier to irradiate product of uniform height and depth with this method,” Clemmons says.
Gamma rays are similar to X-rays but are produced from either Cobalt 60 or Cesium 137 radioisotopes.
With gamma rays, the products are transported around the source in a shielded chamber until the process is complete. Gamma rays are photons and can penetrate whole cartons of food product. These systems operate continuously. When not in use for treating products, the gamma source is generally kept in a pool of water, which absorbs the radiation harmlessly and completely.
Clemmons says there have been great advances on the gamma side. “There used to be issues on distributing even doses, but now this is possible with gamma ray irradiation,” he says, adding that this method is the least expensive and provides the most product penetration.
The X-ray machine is a more powerful version of the machines used in many hospitals and dental offices. X-rays are produced when electrons exiting an accelerator strike any material. To produce useful quantities of X-rays, a tungsten or tantalum metal plate is attached to the end of the accelerator scan horn. The electrons strike the plate and are converted into X-rays, which pass through the metal plate and onto the product being conveyed underneath. X-rays can penetrate whole cartons of food, be switched on or off and also require shielding.
“X-rays have great penetrating power, but from an efficiency standpoint, you’re losing 90 percent of the system’s capabilities when you hit it off a target to create photons. Consequently, there is an issue of wasted electricity,” Clemmons says. “Also, in some instances, there are problems with processing speeds. Although you can irradiate larger volumes with X-ray systems, you have to slow it down due to the process.”
Use of Irradiation
Eustice says about 15 million pounds of irradiated ground beef and poultry is marketed annually in this country. “The companies that are thoroughly committed to the process continue to market their products as irradiated,” he says.
The majority of irradiated meat, however, is ground beef. “Poultry was slow to catch on, but there is a huge advantage to irradiating boneless breasts and boneless thighs,” Clemmons says. “As ground beef catches on, there will be advantages in the poultry industry.”
He says with pork, irradiation takes care of the trichinosis risk. “More restaurants will be able to serve medium-rare [irradiated] pork chops,” Clemmons says.
Food Technology Service currently irradiates 12 million pounds of food annually using gamma ray technology, according to Rick Hunter, CEO. “Irradiation provides another barrier in a multiple-barrier approach to food safety,” he says.
One of its clients is Omaha Beef, which has been irradiating its bulk ground beef and burgers since the fall of 2000. The impetus for this was the concern of company president, Bruce Simon, about the potential of E. coli. According to Beth Weiss, corporate communications director at the company, the use of irradiation did not negatively affect ground beef sales. “It does cost us more money to produce irradiated ground beef, however, we decided not to pass this expense on to consumers. It is a cost of doing business that the company has absorbed,” she says.
Currently, ground beef is the only Omaha Beef product that is irradiated. Weiss says this is because, with whole-muscle meat, bacteria are on the surface and more easily killed during cooking. “If there ever was concern with other products, irradiation would be something we would look at because of our excellent experience with this technology,” she says.
Huisken Meats, based in Sauk Rapids, Minn., sends its frozen private-label ground beef patties to Sadex for irradiation. The company has been irradiating product since May of 2000. Clifford Albertson, general manager and COO, says irradiation is the only definitive step in eliminating any issue with E. coli. “There are a number of other interventions that the beef industry has adopted for the past number of years that have been cumulatively effective, as reflected in the decreased number of foodborne illness incidences,” he says, adding that he believes irradiation should be used more often.
Huisken Meats also builds the irradiation costs into the price of its meats. “A significant portion of the cost is transportation [of the product to and from the irradiation facility]. But the cost of irradiating the product is a matter of a few pennies a pound,” he says.
Like Omaha Beef, Huisken Meats has had no negative consumer responses regarding its irradiated product in recent years. “There were some activists in the past that generated letter-writing campaigns, but that hasn’t happened in years,” Albertson says.
Hunter says the future of irradiation is dependent on the meat industry’s interest as well as economics. “I think the rapid and increasing usage of irradiation in the produce industry will [spur increased interest from other industries],” he says. “The U.S. government has entered into framework equivalency agreements to allow imports and exports of irradiated fruit and vegetables to eliminate insects. Also, we are awaiting FDA approval on irradiated hot dogs and lunchmeat. As these products reach retailer shelves, they will serve to further enhance consumer understanding of irradiation.”
Clemmons agrees, saying that he knows of at least one major upscale supermarket chain that plans to promote irradiated products in the near future. Eustice says the industry is on the doorstep of a sea change of sorts.
“Irradiation will do for ground beef what pasteurization did for milk,” he predicts. NP