Perhaps the most common and most easily understood non-chemical cleaning technology is steam pressure cleaning. It combines the simple age-old cleaning principles of pressure blasting to remove dirt, grime and organic matter and hot water/steam to kill bacteria.
"Most plants use hot water that comes off the boiler through hoses, using foamers, liquid chemicals and sanitation agents," says Bill Hannigan, vice president marketing for Sanitech (www.sanitechcorp.com), Lorton, Va. "We can combine everything into one step using only cold or warm tap water put under pressure."
The "wet steam" process is not a vapor process, which Hannigan says might be great for sanitizing but not for cleaning. Sanitech's system employs water that may reach temperatures of 300°F at high-pressure application.
"The traditional pressure washer spits out water at the same temperature of 140°F that it went in at," says Hannigan. "It is applied at a temperature of 2,000-3,000 psi and use four to eight gallons per minute to knock off debris. It can have great cutting power and blast a surface clean. Our system, however, uses higher temperature water (300°) and is effective in food processing applications at only 1,000 to 2,000 psi, using only 1.5 to 3.0 gallons of water per minute."
Sanitech wet steam systems come in five portable models (Mark I through V), varying in pressure capability from 1,000 to 2,000 psi. Hoses to the trigger gun control vary in length.
The high heat of water used in Sanitech systems helps break down fat tissue and other organic matter. It also kills dangerous microbes.
Most pressure wash applications, Hannigan maintains, have the negative side effect of sending dangerous bacteria such as listeria and E. coli airborne, spreading them through the plant without killing them.
"With steam, however, they are killed on contact," he says.
Sanitech counts brewer Anheuser-Busch among its customers. Cheese plants, meat, seafood processors, beverage makers and vegetable processors all use a lot of water and are candidates for the systems.
Superheating for super cleaning
In 1984, an Italian bartender working in a German bar made a "eureka" discovery while washing bar glasses. Knowing that glasses with lipstick stains were difficult to clean, he walked over to the cappuccino machine and noted the remarkable ease with which the steam from the coffee maker removed the stain. That cappuccino machine became the model for the dry - a.k.a. superheated - steam cleaning equipment sold today by Atlanta-based AmeriVap Systems (www.amerivap.com).
The system evolved today's fully developed industrial machines. The Xtreme Steam industrial system is a superheated vapor system that deep cleans and sanitizes with saturated dry steam. The unit's boiler heats water to 365°F. Steam exits the unit at 265°F at an adjustable pressure of 0 to 150 psi.
|AmeriVap's industrial cleaning system uses "dry" steam to deep clean and sanitize.
Superheated vapor refers to steam created at temperatures far above the boiling point of water. Superheated vapor combines the solvent power of water with high-temperature cleaning capability. The system will kill salmonella, E. coli, botulism and listeria contaminants. System benefits include, among others, reduced need for cleaning chemicals.
"The system heats water to such a high degree that it becomes an extremely hot vapor," explains Werner Diercks, CEO for AmeriVap. "It cleans everything and won't damage the equipment."
Diercks emphasizes the difference between the system and a pressure washer. Xtreme Steam is a dry steam cleaning system. The emitted dry steam contains only five percent moisture, making it safe in sensitive areas of the plant.
"It excels in areas where you can't use water - sensitive equipment, touch screens, motors, anything electric and sensitive to water," says Diercks. "It is also effective where you have crevices and hard-to-get-to, tough-to-clean areas."
The system can be used on scales and sensors, conveyors, wrappers, slicers and dicers, feeders, gaskets, electrical panels, refrigeration systems and more.
To date, bakeries have been among the most avid users of the system, followed closely by meat and poultry processing plants and confectionery processors. Current users of the system include Pepperidge Farm, Quaker Oats, McKee Foods and Nestle.
The raw product in meat operations makes equipment and the adjacent plant area highly susceptible to bacterial contamination. Meat processors employ dry steam with a technique called "tenting" to clean their equipment.
"They throw a tarp over the equipment, fill it with steam, and hold the temperature at 180°F for 15 minutes," explains Diercks, noting that a Land O'Frost plant in Arkansas is currently using the system. "Everything is heated. [Conditions are so hot that microorganisms are easily killed.] Push steam through drains and listeria is history."
A silver bullet
Hey-oh! Silver is back!
One innovative "emerging" sanitation technology is, ironically, thousands of years old. Ancient Egyptians, it seems, used to line urns with silver to prevent contamination of the contents.
"It's a technology that sat idle for a long time," laughs Mark Massie, sales manager for Bioguard Plastics, based in St. Paul, Minn. Bioguard has a licensing agreement with AgIon Technologies to use the latter's anti-microbial technology for cutting boards and other applications in foodservice and food processing operations.