WHY STAINLESS STEEL?
Stainless steel is probably the only choice in professional kitchens to ensure high hygiene and durability. One of the key reasons why stainless steel is chosen for industrial applications is its resistance to corrosion. This steel alloy contains more than 10.5% chromium. The higher the chromium content of an alloy, the lower the chance of corrosion.
Stainless steel is also popular for its neutrality - when interacting with food, stainless steel does not have or cause smell or taste, does not change its natural appearance, and does not accumulate or promote bacterial growth. This metal alloy has a high thermal resistance, e.g. it does not deform when hot dishes are placed on the stainless steel surface, is easy to clean and has a long service life.
WHICH STEEL TO CHOOSE?
MOST POPULAR CHOICES FOR CONVENTIONAL KITCHENS:
AISI 304 is the most common steel used in professional kitchens. As standard, this alloy contains about 18% chromium impurity, 9% to 10% nickel. This provides greater resistance to corrosion. AISI 304 steel is not magnetic.
AISI 201 - stainless steel alloys use manganese instead of standard nickel impurity. Changing the main alloying agents from nickel to manganese makes this metal less expensive than the 300 series steels. Mechanical and physical properties are similar between the alloys compared. This type of steel is not magnetic.
STEEL FOR AGGRESSIVE ENVIRONMENTS
AISI 316 - commonly used in aggressive, chlorinated environments and on ships, in outdoor kitchens, beach restaurants, or in places where fish and/or meat are processed (slaughterhouses). It is also used in kitchens where hygiene requirements are particularly high or in the medical sector.
As standard, AISI 316 alloy has a higher added content of molybdenum (recommended at least 2%) and nickel compared to AISI 304 type. The added molybdenum and nickel content provides increased corrosion resistance in most of aggressive environments. The added materials also increase strength and resistance to deformation at higher temperatures. The alloy retains good mechanical and anti-corrosion properties below 0 °C. AISI 316 steel is not magnetic.
PASSIVATION
What is passivation?
Passivation layer - is a naturally occurring layer of micro-coating that is formed during production or naturally as the metal oxidizes in air. Sheets of metal usually arrive at factories which produce professional kitchen equipment with this passivation layer already formed.
For the maintenance of stainless steel products, it is recommended to passivate them additionally with specially designed products. The additional passivation thickens the protective film (passivation layer), which makes the metal more resistant to corrosion and other external influences.
When removing rust from metal (scrubbing the rusted area, using chemicals, etc.), it is mandatory to passivate the cleaned area after all cleaning procedures. Passivation is a special process that will collect the free iron and naturally form a new passivation layer (protective film).
DAILY MAINTENANCE OF STAINLESS STEEL
Although maintenance of stainless steel is simple, it is important to know the basic rules and possible maintenance mistakes to avoid in order to keep surfaces in good condition.
To ensure the durability, cleanliness and quality of stainless steel products, sanitation can only be carried out with suitable chemicals.
Wrong materials or incorrect cleaning method can damage the surface, leading to stains, discoloration, structural variation or even corrosion marks.
HOW TO CLEAN STAINLESS STEEL PROPERLY
Choose the right cleaning products:
- Protective cleaning equipment - safety goggles, gloves and appropriate clothing.
- Cleaner - adapted for stainless steel, pH 7-11, food contact, ready to use (not concentrate).
- Clean microfibre washing and drying cloths, free of contamination from other cleaning agents - excellent at absorbing and attracting dirt; getting into the smallest crevices, leaving no lint or cleaning marks
- Clean, soft water (non-calcified)
THE CLEANING PROCESS:
1. New products have protective plastic films. Remove them first to avoid future traces of hard-to-clean adhesive that can cause corrosion.
2. Follow the instructions for use on the cleaning product leaflet.
3. Clean the surface with a cleaning agent in the direction of the stainless steel abrasive.
4. Rinse cleaned surfaces with clean, warm water.
5. Dry with a clean, dry microfibre cloth.
Regular maintenance of stainless steel will help to keep the products durable and hygienic.
WHAT NOT TO USE FOR CLEANING
- Do not clean stainless steel surfaces with cleaners containing :
• chlorine
• salt
• citric acid
• vinegar
• soda
• scouring powder (abrasive)
2. Do not use products that are not suitable for the care of stainless steel (floor and tile cleaners and mops, disinfectants, etc.)
3. Do not mix several different cleaning products at the same time.
4. Do not leave on the surface:
• cast iron cookware
• citrus fruits
• salt
• mustard
• pickle vegetables
• mayonnaise
• and other reactive substances.
5. Do not let the cleaner dry on the surface to be cleaned.
6. Do not use abrasive sponges (steel pumice or abrasive sponges). They can damage metal surface and lead to corrosion.
7. Do not let the water dry on the surface to be cleaned - traces of corrosive limescale may remain.
RUST IS A CONSEQUENCE OF IMPROPER MAINTENANCE
Although stainless steel products have a high resistance to corrosion, improper use or maintenance is a natural consequence of corrosion. When rust is observed on stainless steel products, it is important to stop the corrosion at an early stage to avoid major damage.
RUST CLEANING AND CORROSION PREVENTION:
1. Remove easily removable rust with a clean cloth and clean, warm water.
2. Use a special rust remover (liquid/abrasive) to remove any remaining rust.
It is recommended to test the product on surfaces in an invisible place before use.
3. Scrub the cleaner with the cleaning agent in the direction of the abrasive on steel, only at the rust point. Scrub the corroded area until all rust is removed.
4. Rinse the rust cleaning area well with clean, warm water. A poorly washed surface can become a source of corrosion in the future.
5. After rinsing with clean, warm water, dry the surface with a dry, clean microfibre cloth.
6. If rust is still visible on the surface, repeat the process.
7. At the end of the cleaning process, apply a special passivating agent to the cleaning area to protect the surface against rust.
Proper daily maintenance of stainless steel products ensures their longevity and preserves quality characteristics.
To ensure hygiene in a professional kitchen, it is recommended to clean stainless steel surfaces daily.