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Stainless steels enable food processors to maintain hygienic conditions in long-lived
equipment
By Carroll McCormick
Nickel Magazine, July 2007 -- Poultry is one of those common everyday
foods that must be processed under strict sanitary conditions. Otherwise the potential for contamination by
disease-causing micro-organisms is unacceptable.
To ensure hygienic conditions, such food processing facilities are cleaned frequently, with close
attention to detail. High-pressure washing several times a day removes accumulated residues, and specialized
chemicals are used to kill micro-organisms.
Food processing companies must meet stringent government-mandated standards in swab tests and surface
pitting. Stainless steels resist corrosion in the chemical cleaning environments and their surfaces remain
smooth and free from the pits or etching that would allow bacteria to adhere to less-durable materials.
Stainless steels also resist wear as well as corrosion, giving long service in food processing equipment.
When ACA Co-operative Limited in Canada modernized its plant in Nova Scotia’s Annapolis Valley, it
purchased 40 pieces of the latest-generation of austenitic stainless steel processing equipment. The
expansion totals 1,400 square metres and the plant processes 28 million kilograms of poultry annually.
ACA purchased the equipment from LINCO Food Systems. The company has manufacturing facilities in Denmark
and Holland and supplies equipment worldwide for the poultry meat processing industry. Most of the poultry
processing equipment LINCO manufacturers uses
S30400 wherever the poultry comes into contact with the processing equipment, as well as in equipment
frames, motors and gear boxes.
“Equipment manufacturers know that stainless is the most durable metal for poultry processing equipment;
indeed it’s the industry standard,” says Malcolm Keith, who manages preventive maintenance at ACA
Co-operative. “We expect the equipment to last a long time.”
“For what the equipment is used for,
S30400 is more than suitable,” says LINCO Food Systems service manager Torben Vester. “We haven’t seen
anywhere that
S30400 won’t cut it. We have no problems with corrosion around the welds. Most of the equipment is
acid-treated in a dip bath [to restore the protective oxide layer on the steel].”
The operating environment in the ACA Co-operative processing rooms is very humid, and not only during
cleaning operations, when steam from the hot cleaning water can make it hard to see the far end of the rooms.
During cleaning operations, steam condenses on other parts of the plant so that stainless steel (mostly
S30400) is used for non-process items such as doors, doorknobs, hinges, shovels, handrails, and even
clipboards.
Years ago, galvanized steel and aluminum were widely used in food processing plants. However, the zinc
coating of galvanized metal eventually disappears, exposing rusty steal. Aluminum corrodes and pits,
rendering it more difficult to clean, and unsuitable not only for food-grade surfaces. It also lacks the
strength for applications that involve vibration, bending and shock loading. As in other sectors of the food
processing industry, where harsh conditions and the need for cleanliness prevail stainless steel has largely
replaced other metals.
Carroll McCormick is a Montreal-based freelance writer.
Photos: Carroll McCormick for Nickel Institute and iStock.
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