This past April, when Wal-Mart Stores Inc. announced plans to implement additional process-control standards for its ground-beef suppliers, the news triggered plenty of questions and concerns among processors. In addition to complying with the retailer’s testing regimen for E. Coli O157:H7 and its prevention-based certification global standards, the company rolled out a plan requiring slaughtering operations and beef-processing plants to implement validated food-safety interventions to meet new standards by June 2011. Slaughtering facilities will be required to achieve a 3-log reduction for E. coli O157:H7 (and Salmonella) by the 2011 deadline and an additional 2-log reduction by June 2012. Ground beef suppliers must implement interventions at their plants that result in a 2-log reduction for E. coli by the 2011 date.

The implications of Wal-Mart’s mandate for meat processors is just one of the issues Dr. Jim Marsden, Regents Distinguished Professor of animal sciences at Kansas State Univ., plans to discuss at an annual conference focused on controlling E. coli. Hosted by the North American Meat Processors Association, Marsden and many other food-safety experts will focus on technologies, regulatory compliance, best practices and detection methods related to the pathogen at the conference: “Prevention of E. coli O157:H7 for Further Processors,” Sept. 28-29 at Chicago’s Four Points by Sheraton Hotel at O’Hare International Airport.

Proven technologies
Marsden has recently been consulting with a Salt Lake City-based processor, Wasatch Meats Inc., where an innovative system is being tested to decontaminate beef trim prior to the grinding process. Marsden says the system is also successfully used to treat subprimals prior to the bladetenderization process. The ultra-violet light-based system is one technology Marsden will highlight during his presentation at the NAMP event.

While traditional methods of treating subprimals decontaminates just one side, Marsden points out “on this test they’re getting a 360-degree treatment. It’s a different technology that is designed so that they get U.V. penetration on all sides,” which is critical for treating beef trim and allows for treatment of all subprimal surfaces, not just one surface that is subsequently blade tenderized. Using a tunnel equipped with U.V. panels designed to create oxidative gasses so they have the effect of the U.V. on all sides, the technology is particularly convenient because it is a dry treatment that doesn’t require chemical mixtures or spraying of water on the product, which is not permitted in ground beef. The processor has achieved 2-log reductions when using the technology to treat trimmings and more than a 3-log reduction when used on subprimals.

Another E. coli-related project Marsden plans to highlight in his presentation is one he served as a consultant on for Maid-Rite Steak Co. Inc., based in Dunmore, Pa. Like most grinding operations, the company mixes 50-lb. blocks of frozen blocks of beef with fresh beef. And, like most operations, controlling E. coli in the frozen blocks is challenging. Maid-Rite has developed a system that includes treating the blocks of beef first with acidified sodium chlorite, before the block is broken up, followed by another treatment of acidified sodium chlorite while it is exposed to U.V., which has yielded positive results. After using the system for about a year, Marsden says the company has realized significant success in controlling E. coli over a long production period and he will outline some of those improvements during his presentation.

The Wal-Mart factor
Because Wal-Mart announced new pathogen-reduction requirements for its ground-beef suppliers earlier this year, Marsden anticipates many attendees will be interested in his comments on the initiative. Before announcing its more-stringent requirements, Wal-Mart food-safety officials first contacted Marsden to ask him if their expectations were reasonable. His opinion was noted and verified by the company’s suppliers, he says.

Requiring grinding operations to be able to achieve a 2-log reduction, he says, was first met with some angst in the industry. However, “I’m going to explain how relatively easy it is to get that 2-log reduction,” pointing out that companies like Jensen Meat Co. have successfully operated with this capability using Sonova spray treatments for several years. “And now other technologies are emerging that allow you to get that 2-log reduction with a minimal investment,” he says.

Marsden will also address technologies available, including some that address Wal-Mart’s requiring slaughtering operations to be able to document a 5-log reduction. His presentation will highlight a number of technologies that can be used as a multiple-hurdle approach to achieving that goal. One point that needs to be made relating to Wal-Mart’s requirement is that slaughtering operations are requiring a “theoretical 5-log reduction,” to accommodate cattle arriving at plants clean. If an animal arrives at the plant and doesn’t have 5 logs to remove, Wal-Mart doesn’t require achieving that reduction.

“They are saying if there are 5 logs or more, your process should eliminate that,” Marsden says. “It’s not that you have to have that reduction documented in the plant day in and day out. It just means that your process is capable of delivering that reduction.”

While the announcement by the retailer made many headlines initially, Marsden says he has heard no grumbling about the requirements among processors once they understood the specifics. “Once it soaked in exactly what it was they were looking for, especially on the slaughter side, companies like Tyson, Cargill and JBS were already in compliance. On the processing side, I think it’s just a matter of making some adjustments in the process and getting in compliance pretty easily.”

Pre-harvest approach
Controlling E. coli using pre-harvest interventions is the focus of another presentation at the NAMP event. Dr. Guy Loneragan, professor of food safety and public health in the department of animal and food sciences at Texas Tech Univ., Lubbock, will provide an update of current technologies available at the pre-harvest level to control E. coli O157:H7 as well as reviewing promising technologies that will become available soon. He points out that the pre-harvest technology applications are not limited to beef production operations, but are applicable to treating dairy cattle as well.

Technologies applied prior to slaughter typically fall into one of three segments, according to Loneragan, including: biological control (including probiotic- and bacteriophage-based interventions); vaccine control; and chemical control/feed additives, including sodium chlorate “and another product that we’ll discuss at the conference.”

“I’ll also get into how these technologies contribute to an overall multihurdle approach to food safety,” he says. Future needs and contributions the technologies offer to the entire food-safety supply chain will also be addressed. The focus of his presentation will then shift to a macro level, as Loneragan will encourage attendees to consider not only “if” the interventions work and how they could be implemented, but “should” they be incorporated. “That gets into some of the future research of what is the contribution and what is their value within a production system.”

Loneragan says while many of the newer interventions to control pathogens show promise, the threat posed by E. coli cannot be eliminated by simply plugging in a technology into an operation. As the industry continues to search for solutions, he points out, “It’s not going to be a single intervention and it’s not going to be a matter of just stacking interventions on top of one another.”

Instead, developing real-world solutions involves understanding how each intervention contributes to the overall system. The food-safety goal for the industry should be to discover how to design a cross-sector system to ensure public health. “We’re trying to better understand how we can employ technologies and interventions in an informed way to make a system that ensures we continue to supply wholesome products,” he says.

The promise of vaccines used to control E. coli has gained plenty of attention dating back to 2006, when Canada’s Bioniche Life Sciences introduced a vaccine to control O157:H7 in live cattle. The vaccine has not yet been granted a conditional license in the US but is used in Canada. However, Epitopix, based in Willmar, Minn., received conditional approval from the US Dept. of Agriculture in early 2009 to sell its E. coli vaccine to beef-cattle producers and processors. Based on field tests, the vaccine eliminated 99 percent of the pathogen among cattle testing positive for E. coli. It reduced the overall number of cattle testing positive by 85 percent. Vaccines, says Loneragan, are but another arrow in the quiver of food-safety officials. “We know how to use vaccines so this is an easy implementation to some degree,” he says, pointing out that despite some challenges, this type of control is effective. With a variety of interventions being refined and proven successful in controlling E. coli, “We’re fast approaching having a toolbox of a variety of different interventions,” says Loneragan. “In a short period of time, we hope the producers who want to implement an intervention can choose the one that best fits their production system.”

Testing technologies
Interventions designed to control E. coli represent one part of any foodsafety system, but testing and verifying the effectiveness of the technologies is the other vital step. When it comes to detection and testing for pathogens, time is money for processors.

Magnetic nanotechnology is behind the pathogen detection technologies offered by FoodChek Systems Inc., based in Calgary, Alberta, Canada. Specifically designed for processors of ground beef relying on fast and accurate testing methods for E. coli, the company recently launched its FoodChek E. coli O157 Test, billed as the fastest test method available for 375 gram RGB and N-60 Trim sample screening that is AOAC-approved and USDA-accepted.

Offering processors same-shift, validated test results for E. coli O157:H7 in less than eight hours, facilitates faster product-release times and limits the costs associated with holding products without compromising food safety or brand integrity. After a sample enrichment of six to seven hours, a portion is transferred to the FoodChek test cassette and placed in a reader where E. coli O157 can be detected at levels as low as 1 CFU/375 gram sample. Test results are displayed on a reader screen, printed and stored for electronic transfer.

DuPont Qualicon’s Bax System relies on a real-time assay and a one-stage enrichment to provide processors same-day results accurately for “real-world sample sizes of raw ground beef and beef trim,” says Megan DeStefano, global marketing manager with DuPont Qualicon.

Test results for E. coli O157:H7 using the DuPont technology is made faster by not requiring initial cell concentration steps.

“It is also extremely accurate, detecting all known E. coli O157:H7, including cluster A and rough strains,” DeStefano says.