Common sense cleaning techniques and developments in design work in tandem to keep a conveyor clean.
It would be difficult, if not impossible, to find a meat product that doesn’t end up on a conveyor belt at one point or another. Given their importance in a processing plant, a good conveyor has to run well and also have the ability to be quickly and thoroughly cleaned and sanitized.
“No matter how clean the machine that slices the meat, or how cleanable a machine is that grinds the meat, none of it makes any difference if the conveyors aren’t cleanable and kept in good shape. You’re seeding the product with bacteria if you’ve got a belt that’s harboring bacteria,” says Barry Whitman, vice president, market development, of Mol Industries, Grand Rapids, MI.
Bacteria does not grow on the belt itself, but rather on the fat, protein, and other materials that are deposited on the belt by the product, says Tyson Gabler, applications engineer for uni-chains, Reading, PA. “For this reason, the belts should be cleaned every day or sometimes several times a day.”
Choosing a sanitary conveyor system is an important first step for a company. Dan Karpy, president of NeXtconveyor (formerly Materials System Engineer Corp.), Tampa, FL, says that in order to properly clean conveyors, a plant must first get rid of the perception that conveyors are a cheap off-the-shelf item. “Conveyors are as much of a critical control point in all food process lines as metal detectors and X-ray inspection,” he says. Treating a conveyor as a last-minute purchase can result in a system that is inadequate for a plant’s sanitary needs.
Conveyors are being designed with improved sanitary characteristics, but regular cleaning is still essential. “You have to follow the sanitation chemical manufacturer’s instructions to the letter,” says Rick Spiak, director of sales and marketing for Wire Belt Co. of America, Londonderry, NH. “Use the right cleaning agents, get all the debris off the conveyor, and make sure that every non-exposed area is clean.”
Chris Celusta, manager, food processing sanitation for Spartan Chemical Co., Maumee, OH, likens the sanitizing training employees must undertake to spring training for baseball. “Even the ‘veterans’ need a friendly reminder of how important the fundamentals are,” he explains. “We stress hands-on training on a periodic basis to reinforce the cleaning process.”
Celusta says that some facilities disassemble the belts and clean them in designated wash areas or place them in clean-out-of-place (COP) tanks with a low-foam chlorinated product. “COP tanks will heat the product up to 180 degrees, and from there they will have the belts set for thirty minutes to an hour,” he says.
Other facilities use a chlorinated/alkaline cleaner, which does a good job of breaking down proteins and biofilms. Most foam applications allow the product to set for 15 to 30 minutes. “This allows the product to penetrate, emulsify, and suspend the soils,” he says. Spartan offers a variety of foaming chlorinated and non-chlorinated products.
Ecolab Inc., St. Paul, MN, also recommends keeping the basics in mind, noting that the four basics of a cleaning and sanitizing program are chemical concentration, time, mechanical action, and temperature. “Every type of meat fat has a different melting point,” says LouAnn Marshman, technical affairs specialist, “so during pre-rinse, you would want to make sure your water temperature is at the melting point of whatever the meat is [that was on the conveyor].”
After pre-rinse, employees would foam the cleaner on to remove the soils, followed by a final rinse and sanitizing with a no-rinse EPA-registered sanitizer, Marshman says. Not every sanitizer is the same, so she says it is important to read the label. Ecolab’s Vortexx sanitizer, for example, is effective against Staphlyococcus, E. coli, Listeria, and Salmonella, among others, and has label directions for use in continuous belt treatment. The company also has a recommended treatment program system.
“We require a spray bar on the top and bottom of that belt, so you’re spraying both sides,” she says. “We recommend a continuous process, and we have specific requirements as far as the size of the nozzle, distance from the belts, and the number of nozzles.”
Many people believe that high pressure is the best way to clean conveyor belts, but Zep Mfg., Atlanta, GA, disagrees. Phil Ellis, senior chemist, says, “This can create a potentially hazardous situation by creating aerosolized water droplets, which could be contaminated with Listeria or other microorganisms. Getting back to the basics — applying physical agitation, either using scrub pads or brushes — will make a big difference in the end results.” Along with foaming products and chlorine sanitizers, Zep offers food processing scrubbers and dispensing equipment.
Ellis also says that all the conveyor surfaces be cleaned, not just the food contact surfaces. The top and bottom of the belt, the wear strips, sprockets, guides, and framework all need to be sanitized, he notes. “Choosing the right conveyor in the first place can save you a lot of headaches in the future,” he adds.”
The design of the belts plays a major role in the amount of work needed to completely clean and sanitize them. Plastic modular belts, for example, have many hinges where product and bacteria can hide, resulting in a difficult-to-clean system.
Uni-chains has patented the first and only modular plastic belt to be issued the USDA Equipment Acceptance Certificate for meeting the NSF hygiene requirements standard in meat and poultry processing. “The belts are designed to have hinges as closed as possible when belts are running on the conveyor, so there are no gaps for the bacteria to grow,” says Gabler. “These very small gaps are hard to clean if something does grow there, so they are designed to open up for cleaning when the belts ‘bend’ around the sprockets.”
Other companies have turned to different materials and designs to assist end-users in the cleaning and sanitizing process. As with other processing equipment, there are many options. “Choosing a cleanable conveyor belt, made from food-approved materials, is critical,” says Jonathan Lasecki, engineering manager for Ashworth Bros., Winchester, VA. “The conveyor belt must also be impervious to all commonly-used cleaning agents.”
Ashworth Brothers offers the Advantage 120 and Advantage 200 systems, which utilize plastic modules “floating” on stainless steel cross-rods through a patented rod-lock mechanism. “This design allows an exceptionally large open area, which is easy to clean, without using hinges,” says Lasecki.
The location of a belt in a processing plant also plays a part, as some areas of a plant require tougher cleaning treatments. “If you have a conveyorized oven, the belt will get pretty gummed up with baked protein onto the belts, sprockets, shafts, and other conveyor parts,” says Spiak of Wire Belt Co. of America. “You have to use a caustic cleaner to get that off, then use a regular scrub or foam, and then some kind of sanitizer. You don’t want to sanitize the crud that’s on there, so you’ve got to get it off first.”
Wire Belt Co. of America uses an open mesh made of wire in its conveyor belts. “It’s made of round wire, so everything is going to run off,” Spiak says. “It’s a very open, very clean design, and it gives great drainage.”
NeXtconveyor’s Karpy says companies should follow the adage of ‘if you can’t see it, you can’t clean it.’ “You must take it apart,” he adds. “The conveyors should be disassembled to the highest degree possible.” To that end, the company’s NeXtgen Sanitary Mezzanine/Scale Platforms feature a “tool-free” disassembly. “Our conveyor can be stripped down to the bare frame in minutes,” Karpy says. “The frame construction eliminates fasteners wherever possible. Our skid rails drop in with no screws.”
Mol Industries’ Whitman says that companies can sanitize a belt using water spray or deep cleaning in tubs, “but that’s very expensive too. You’re talking about a lot of water usage, because you’ve got to fill the tubs to soak the belts,” he says.
The company’s ThermoDrive is sprocket-driven and has no hinges, and it is 60-percent lighter than modular belting, Whitman says. The belts also do not have to be taken off the conveyor for cleaning.
“The best thing a processor can do is use a hygienic belt that conforms to the AMI standards,” says Whitman. “It’s cleanable to a microbiological level, and it has no niches that can harbor bacteria.” NP
Equipment and supply manufacturers participating in this feature include: