Stainless steel is a versatile alloy that is corrosion resistant, durable and easy to clean - making it ideal for use in the food processing industry. There are different types of stainless steel specifically designed for contact with food, collectively known as food grade stainless steel.
Stainless steel contains at least 10.5% chromium which forms a passive layer on the surface that protects it from corrosion. This oxidation resistance also means stainless steel:
• Is resistant to staining and discoloration - retaining a clean appearance over time
• Does not react with or contaminate foods with particles or chemicals
• Is non-toxic and biologically inert, posing no threat to people who consume food that comes into contact with it
•Allows for proper sanitation - stainless steel surfaces can be thoroughly cleaned and sterilized
301: The most basic and lowest grade stainless steel used for food processing. It is not recommended for repeated high heat or corrosive environments.
304: The most commonly used grade, containing 18% chromium and 8% nickel. Highly resistant to corrosion and staining. Suitable for use with most food and beverages.
316: Contains 2-3% molybdenum which enhances rust and corrosion resistance. Ideal for use with salty, acidic or sugary foods. Commonly used for equipment in dairies and breweries.
Duplex Stainless: A combination of ferritic and austenitic stainless steel. Has higher strength, hardness and resistance to corrosion from chlorides. Generally more expensive.
The final surface finish of stainless steel used for food applications also impacts its suitability:
• #2D - bright and abrasion resistant. Used for visible parts and high wear areas.
• #4 - satin finish. Good balance of appearance and abrasion resistance.
• #8 - matte finish. Hides surface imperfections and minimizes fingerprints. Most commonly used.
•Brushed textures provide a hygienic surface that iseasy to clean and resists bacterial accumulation.
• Polished surfaces and #8D finishes give stainless steel an attractive finish but are more difficult to clean properly.
Food grade stainless steel is used in a wide range of applications across the foodservice and food processing industries:
• Kitchen equipment - sinks, counters, dishes, appliances
• Food processing equipment - tanks, vats, pipes and conveyor belts
• Bakery equipment - ovens, mixers, utensils
• Dairy equipment - pasteurizers, tanks, silos
•Beverage equipment - brewery kettles, tanks and piping
•Commercial refrigeration - refrigerator liners
Stainless steel is ideally suited for use with foods due to its corrosion resistance, durability and non-reactive properties. Different grades of stainless steel achieve varying levels of corrosion resistance, with grades 300 through 316 commonly used for food applications. The surface finish also influences suitability, with brushed or matte finishes generally preferred. Properly specified food grade stainless steel ensures equipment and facilities meet requirements for safety, performance and aesthetics in the food and beverage industries.