Food safety officials at Land O'Frost make Listeria prevention and detection a priority at the company's processing plants. 

Meat processors have to stay competitive in this ever-changing market. Staying competitive often means keeping some information proprietary – including ingredient formulations, processing procedures, and even packaging technologies.

As a processor of ready-to-eat meats, Munster, Indiana-based Land O’Frost follows this philosophy in all aspects of its production except one – food safety. When it comes to its food safety practices, Land O’Frost is, and always will be, an open book.

“Back 15 or so years ago the board at NAMI [the North American Meat Institute – then the American Meat Institute] voted to make food safety a noncompetitive issue,” says Matt Henderson, director of food safety at Land O’Frost. “We participate in workshops and continually share a lot of food safety information with our competitors.”

When it comes to Land O’Frost and other RTE meat processors, one of the biggest food safety concerns in the processing facility is Listeria. Listeria is a foodborne pathogen found frequently in raw foods. It can spread to processed foods through cross contamination, poor hygiene or inadequate processing. There are a few different strains of Listeria, but the most common one associated with foodborne illness is Listeria monocytogenes that can cause serious illness (Listeriosis) or even death in vulnerable people such as the very young, elderly, pregnant or immunocompromised individuals.

Jude Mason, director of consulting and technical services for NSF International further explains, “The biggest challenge when it comes to Listeria monocytogenes is that it’s a psychrotrophic bacteria that grows slowly at temperatures near the freezing point of foods. This means that the chilling of foods while critical for the inhibition of some organisms will not prevent the growth of Listeria and so other preventative controls need to be considered.”

And since RTE meats are cooked at the processing stage and are not reheated or cooked before the consumer eats the product, it is critical that during the manufacturing process there are control methods in place to ensure the product is free of pathogens when it leaves the plant.

“Consumers are relying on us to provide a safe product to them,” Henderson says. “Listeria is of great concern with ready-to-eat products like ours. In our industry, and at our plant, we prepare interventions to deal with that risk.”

 Land o frost
Foaming the equipment is an effective sanitizing method used to clean equipment after use at Land O'Frost. 


“Listeria is present in the environment naturally – in the soil, in animal feedlots…there are a lot of environmental sources outside of our plant,” Henderson says. “It can be introduced into the facility through employee traffic or through the transfer of ingredients into our RTE areas. If it’s brought in and it finds a niche that will support its growth, like inside the equipment where there’s some product residue or moisture, and if our sanitation process fails to eliminate it, then it can grow in those niches and find its way out into the environment and ultimately into the product.

“What we try to focus on is eliminating it from the environment,” Henderson explains. “If it’s not present in the environment, then there’s less chance it will find its way to the consumer.”

When it comes to eliminating Listeria from the environment at Land O’Frost’s three processing facilities in Lansing, Illinois; Searcy, Arkansas; and Madisonville, Kentucky, the name of the game is “seek and destroy,” Henderson says.

“Seek and destroy is a method to evaluate equipment in the ready-to-eat environment for the potential harborage of Listeria. Basically, sanitation is the foundation of our food safety program,” he explains. “We have defining procedures in place for how to clean the equipment. Seek and destroy is our method of evaluating the effectiveness of the cleaning.”

After the defined cleaning procedures are conducted on the equipment, the equipment is then disassembled beyond what’s done on a day-to-day basis and it’s tested for Listeria. “If there is a finding we will adjust our cleaning procedures to address that,” Henderson says.

Another intervention method Land O’Frost uses to ensure the equipment and the product processed on the equipment is free of Listeria is to “cook” the equipment. With slicing equipment, for example, or any other equipment that product comes in direct contact with, “cooking” the equipment to 145?F (pasteurization temperature) in a smokehouse can help eliminate any potential organisms that may be present in the equipment. If the equipment isn’t portable, Henderson explains, “We can tarp the equipment or cover it with plastic and inject steam to bring it up to temperature – effectively pasteurizing it.”

 Low Angle
Each piece of equipment at Land O'Frost is thoroughly cleaned and sanitized to help eliminate any harborages of pathogens like Listeria

In situations where the equipment contains electronic components that can’t be cooked or steamed, a more manual, deep cleaning method of sanitation is necessary.

“There is no silver bullet when it comes to preventing Listeria, but there are some obvious controls that can be put into place,” Mason says. “These controls include the use of advanced chemicals to clean and sanitize surfaces with regular changes of the cleaning chemicals to prevent chemical tolerances.”

Other control methods include high pressure processing (HPP) and electronic pasteurization, or irradiation. HPP, which helps control pathogens by applying hydrostatic pressure of approximately 85,000 psi to packaged, ready-to-eat foods, is an effective, but expensive (due to equipment expenditures) technology that eliminates the need for heat treatment.

“Electronic pasteurization, especially when done in the package, affords a tremendous food safety tool, especially with some of the RTE meat products for which we know that Listeria control is a huge problem,” Mason says. “Although electronic pasteurization is not a substitute for hygiene or other food safety interventions, it is another tool that’s going to add a margin of safety.”

In addition, some ready-to-eat meat processors use ingredients that are designed to stop further growth of organisms in the processed product. Antimicrobials such as sodium lactate, vinegar and other natural antimicrobials are capable of controlling the growth of the organism if it is introduced during any point of production. “But the real key is preventing its [the pathogen] introduction in the first place, which comes back to the environmental controls in the facility,” Henderson says. “Environmental controls are how we are able to really affect food safety, by preventing the introduction of the organism into the product through GMPs (good manufacturing processes), clean, dry, uncracked floors, effective sanitation procedures and effective sanitary facility design. When we have all of these elements present in our plants, then we can effectively control Listeria.”

Consumers can do their part by keeping their food as safe as possible prior to consumption. “Consumers need to avoid cross contamination by not touching raw product or produce and then touching RTE foods,” Henderson says.

Mason adds, “Products must not be consumed after their use-by date. And all products should be kept at the correct storage conditions at all times, this includes clean and hygienic storage areas, correct temperature within these storage areas and separate storage of raw and ready-to-eat food products.”