Interventions designed to kill bacteria during the rinse-and-chill cycles in meat and poultry plants are being given greater emphasis by manufacturers and users of antimicrobial treatments. Plant operators are incorporating an array of sophisticated pathogen-killing technologies that can be applied multiple times during processing to minimize contamination.

“Treating meat and poultry with antimicrobial agents is a key way to improve food safety by reducing bacteria on carcasses,” says Keith Johnson, marketing manager, meat and poultry markets, for Ecolab Inc., a St. Paul, MN-based developer of anti-pathogen solutions.

Ecolab, which last summer merged with Redmond, WA-based Alcide Corp., is a supplier of the Sanova®‚ and InspexxTM 100 rinse-and-chill applications. Sanova® developed by Alcide, contains acidified sodium chlorite, and it intended to combat such pathogens in poultry and red meat plants as Salmonella, E.coli O157:H7, Listeria, and Campylobacter.

Agents typically are applied to poultry in a spray cabinet following evisceration and before birds enter immersion chillers. A post-chill dip tank containing Sanova® is another potential application point.

Red meat or beef also can be rinsed with Sanova® following skinning or evisceration. Carcasses often receive Sanova‚ treatments after cooling, and again when the beef arrives at other plants for cutting.

“Multiple interventions also help protect against the cross-contamination that can occur in different steps within a process, or when meat is transported to various facilities,” says Roger Tippett, Ecolab senior research and development program leader for meat and poultry.

InspexxTM 100 is a mixture of peroxyacids that are designed to eradicate Salmonella typhimurium, Campylobacter jejuni, Listeria monocytogenes, and E.coli O157:H7. It can be applied to poultry in spray cabinets and immersion chillers.

Rex Moore, president and chief operating officer of Denver-based Maverick Ranch Natural Meats, a Sanova® user, says it is crucial that his company employ every possible food-safety intervention to both protect consumers and avoid the negative publicity that results from an pathogen outbreak. The company markets beef, pork, chicken, lamb, buffalo, and turkey under the Maverick Ranch brand in approximately 2,000 stores.

In 2003 Maverick became the first U.S. beef company to use Sanova® on case-ready and grinder-ready ground beef, and in January 2004 it began applying Sanova® as a carcass wash at its Colorado Meat Packers boxed beef fabrication plant in Denver, Moore says. Maverick was the first U.S. company to use Sanova® as a primal wash, and incorporates the agent on a post-chill basis to poultry and fully cooked ground ham, he adds.

“We’ve had no incidences of E.coli O157: H7, and we are starting to achieve the same effective kill rates as irradiation without the negative images and perceptions associated with that technique,” Moore says.

Besides the Sanova® treatments, Maverick also leverages such food-safety technologies as steam vacuums, steam pasteurization, organic acid washers, and ultra-violet lights.

“Maverick faces more risk than the larger processors because our products are branded, so it’s very important that we provide the best quality meat and poultry,” Moore says. “In some instances our case-ready ground beef will have gone through three or four cycles of Sanova® during its lifetime, in addition to the additional food-safety measures that are implemented along the way.”

Other techniques being used to kill pathogens early in the processing cycle include a method called Rinse & ChillTM that was developed and is being licensed by St. Paul-based MPSC Inc. During the process, an animal is bled following slaughter and a “superchilled” diluted solution of sugars, and salts is next rinsed through the cardiovascular system where it is converted into lactic acid in the muscle cells. By cleansing blood from the veins and arteries of the animal, the solution helps to drop the pH and lowers by 6Þ to 10Þ  F the internal temperature of the carcass prior to it entering the chiller, says Warner Ide, MPSC president.

Rinse & ChillTM is designed to slow the growth of E.coli and coliform bacteria, extend a product’s shelf life, and provide beef that is consistently bright red in color and more tender, he notes.

“We’re trying to remove blood from the animals at the earliest-possible stage,” Ide says. “It is transforming what used to be the dirtiest part of slaughter into a standard for cleanliness and hygiene.”

The proprietary FDA-approved formulation, now in its third generation, has been in development for 15 years. Originally tested and marketed in Latin America, Rinse & ChillTM is being used in three meat plants in the United States and five in Australia. About 1.2 million head of beef in the two countries were successfully commercialized after undergoing the treatment, Ide says. Two additional beef plants are scheduled to soon install the system.

“It’s always difficult to introduce something new to the U.S. market, and Rinse & ChillTM is a technology that is far more complicated to implement than anyone first realized,” he notes. “But we are working on developments that will make Rinse and ChillTM even more useful.”

Also designed to cleanse poultry prior to chilling is the ZATS (Zep Antimicrobial Treatment System) technology being marketed by Atlanta-based Zep Manufacturing Co.

Intended for the online reprocessing of birds that are contaminated with undigested food or feces during evisceration, ZATS leverages a chlorine dioxide-based antimicrobial liquid to reduce the bacteria, says Stanley R. Weller, Zep chief technical officer, research and development, Acuity Specialty Products Group.

During treatment, the system first flushes the inside and outside of birds with re-circulated chlorine dioxide. The cavities then are drained and flushed again with a pure chlorine-dioxide solution.

Weller says ZATS, which has been available for about two years, is primarily aimed at controlling E.coli, Salmonella, and Campylobacter. It also helps to reduce plant labor expenses by eliminating contamination without requiring carcasses to be removed from a line and cleansed by hand, he notes.

Carcasses that are considered “grossly contaminated,” however, typically must be taken from the line for treatment. About 100 U.S. poultry plants are using on-line reprocessing, Zep estimates.

“This is not a cure-all for poor practices elsewhere in the plant, but an enhancement that helps create safer products,” he adds. “Plant operators still need to pay attention to their overall sanitation and the use of antimicrobials in other steps of their processes.” NP