Keeping a meat processing plant properly sanitized is the responsibility of every employee, but they are not alone in this fight. Manufacturers of processing equipment are making their machinery more and more sanitary, changing the materials or the design to eliminate any breeding grounds for bacteria and biofilm.

Most companies now follow The American Meat Institute’s (AMI’s) “10 Principles of Sanitary Design” or other similar standards. The AMI’s principles state that the machinery must be cleanable to a microbiological level, accessible for inspection, cleaning, and sanitation, and allow no product or liquid collection.

The idea of designing sanitary equipment did not start with AMI’s 10 Principles of Sanitary Design. But prior to AMI’s standards, there were no universally accepted guidelines for designing meat processing equipment, says Brian Sandberg, director of marketing for Formax Inc., Mokena, IL. “Every processor had their own interpretation of what did and did not qualify as sanitary, and specific design requirements often varied dramatically from processor to processor,” he says. “This made it very difficult to standardize our equipment designs and please our entire customer base in terms of machine hygiene.”

Jim Harte, chief engineer of Koch Equipment LLC, Kansas City, MO, says that Koch applies the 10 Principles to all its new equipment design and development. “This has increased the initial machine development time in some cases on new equipment, but the resulting design using the hygienic design approach is always generally simpler and actually can be less costly in production,” he says.

While food safety has always been an important factor in designing food processing equipment, sanitary design has gone from being a nice feature to one of the primary design criteria. “You have to not only design for functionality and worker safety, but you have to design for food safety as well,” notes Scott Scriven, president of Weber Inc., Kansas City, MO. “If any of those three things are lacking in a machine, there’s a limited market for it. If you make a machine that is great on function and worker safety, but you can’t clean it easily, and it can’t operate hygienically, you’ll have a hard time selling it.”

The AMI is just one of a number of standards that exist for food processing equipment. Like other European manufacturers, Townsend Engineering Co., Des Moines, IA, who manufactures in the United States and Europe, also develops and designs products to gain CE Marking from the European Union. Townsend uses a third-party company from Germany to certify its equipment. “Part of the CE standards is that you can self-certify, but you can also certify utilizing an outside party. Clearly, outside certification is a better way of ensuring objectivity,” says Steve Cate, vice president of product development.

When designing a new machine or developing an enhanced version of an existing machine, one common goal among manufacturers is to make the equipment easy to disassemble. Reiser, Canton, MA, is aware of the need to make it easy for a plant’s maintenance crew to expose the areas to clean, clean them easily, and then quickly reassemble. “We understand that if is difficult for the customers to do, they probably won’t do it, so we strive to make it easy for them,” says John McIsaac, engineering/R&D.

Food processing equipment not only needs to be more sanitary, it has to be tough enough to withstand the sanitary practices of a processor. “To improve cleaning efficiency and effectiveness, processors are using more aggressive cleaning agents in combination with elevated temperature and pressure,” says Mark Klossner, strategic market manager – food processing for Boston Gear, Quincy, MA. That cleaning can take a toll on a machine, as the use of aggressive agents can lead to corrosion. “Elevated temperature and pressure during wash down can shorten equipment service life, as components are repeatedly exposed to concentrated force and hot liquid,” Klossner adds.

Every new design or machine enhancement that Townsend develops first goes through the company’s Hygiene Engineering Analysis process, so that every piece of equipment is designed to be as hygienic as possible. The company’s new sausage peeler has been noted by the AMI for its design.

“We electropolished the interior,” Cate says. “With electropolishing, bacteria has a lesser chance or surface adherence. It’s more expensive, but it was the right application to enhance the sanitary design of the product.”

Individual components are vital to the overall machine’s longevity, so Boston Gear offers its family of speed reducers in stainless steel, making them more corrosion-resistant and able to last longer. “We tested and developed the Bost-Kleen series to withstand chipping, flaking, and rusting that result from repeated exposure to aggressive equipment sanitation,” says Klossner.

Reiser makes certain that each successive model of a machine is an improvement over its predecessor, including in sanitation, notes McIsaac. “Otherwise, we don’t do it,” he adds. He says Reiser is constantly looking at new materials that are more chemical resistant and have better water absorption properties, as well as making the machinery more accessible. “We are always seeking out ways to make it easier for our customers to expose the areas to clean, clean them easily, and easily reassemble the machine.” For example, on the company’s Vemag HP stuffer, the doublescrew pumping element and its housing are easily removable from the machine for full sanitation and inspection.

While the processing machines come in the most direct contact with the product, packaging machines are not exempt from sanitary design, says Bob Koch, director of sales, food division, for Multivac Inc., Kansas City, MO. “Packaging equipment designed around sanitary standards can help maximize cleaning efforts and minimize the possibility of error,” he says.

Not all of these changes are visible to the naked eye, but that can significantly reduce the risk of contamination. On Multivac’s R530 Zipline thermoforming system, the porous air bladder system has been replaced with non-porous air cylinders. On many other systems, placing hermetic seals on hollow parts or changing hollow parts into a solid part is another important change. “AMI’s guidelines have a category devoted to this point, and manufacturers have eliminated as many of those areas as possible,” Koch says.

Many companies have removed niches and crevices from their machinery, in keeping with AMI’s sanitary design principles. Henry & Sons, Paso Robles, CA, used to fit the funnel of its sausage fillers into the machine, and there were cracks and crevices where the seams came together, says Mark Henry, vice president. “We have since completely eliminated that, and it’s one-hundred-percent welded and polished now. There are no seams.”

Harte says Koch Equipment uses rounded or sloped surfaces. The open design on the company’s Matrix Crossweb® package “minimizes enclosed spaces and mating surfaces and features rounded and angled surfaces that promote complete water run-off and the elimination of microbial buildup,” says Harte. It also uses patented perforated Delrin rollers that enable water to pass through the perforations during wash down for more effective cleanability.

Weber practices sanitary guidelines on its machinery, all the way down to the smallest part. “We could not find hardware in the marketplace that meets the hygienic demands of our engineers,” says Scriven, “so we design and manufacture our own hardware that has smooth radiuses and no flat spots to retain water. If you think of a traditional hex-head bolt, each of those sides, in theory, could be a harborage.” Furthermore, to aid in quick maintenance, the company has almost completely eliminated the need for tools in disassembling its slicers, which just require a wrench to unbolt the blade.

Formax’s forming and slicing equipment are designed in accordance with AMI’s principles, as well as feedback from customers, Sandberg says. The company’s Maxum700® forming system has a pivoting product hopper and conveyor assembly. The hopper and conveyor can easily be pivoted for cleanup with the push of a button and the removal of only four bolts. “With the components pivoted out of the way, access to the machine interior is significantly improved,” Sandberg says. The FXplus™ slicing system has a chambered head design and unibody cabinet construction with double-sealed doors to prevent contamination of the cabinet interior. The integral scale load cells automatically seal when the machine is placed into clean-up mode to prevent cabinet contamination during wash downs.

While designing equipment with an eye toward sanitation, Henry says that manufacturers have to be wary of over-complicating a design. “If you overengineer it and factor in too many things, then you run into problems. Make it simple, basic, yet beefy and sanitary, and life is good,” he says. NP

Equipment manufacturers participating in this feature include:

• Cleanable to a microbiological level

• Made of compatible materials

• Accessible for inspection, maintenance, cleaning, and sanitation

• No product or liquid collection

• Hollow areas should be hermetically sealed

• No niches

• Sanitary operational performance

• Hygienic design of maintenance enclosures

• Hygienic compatibility with other plant systems

• Validate cleaning and sanitizing protocols