A Rust Lesson—According to the North American Association of Food Equipment Manufacturers (NAFEM), contrary to popular belief, stainless steel is susceptible to rusting and that’s the biggest enemy to the shiny material. We see corrosion of iron and steel metals over time as unsightly yellow orange rust. Steel and iron are referred to as “active metals” because they actively corrode in the natural environment. Stainless steel is referred to as “passive metal” because the base iron is alloyed with other metals such as nickel and chromium which provides that shiny protective film. With 12-30% chromium this invisible passive film covers the steels surface acting as a shield against corrosion. The metal becomes “passive” against corrosion. The film is however only millionths of an inch thick so some care is needed to preserve it.

Enemies of Stainless Steel --There are 3 basic things which can break down your stainless steel’s passivity layer and allow corrosion to rear its ugly head.

1. Mechanical Abrasion means those things that will scratch the steel’s surface. Steel pads, wire brushes and scrapers are prime examples.

2. Deposits & Water come out of our tap in varying degrees of hardness. Hard water leaves spots and when heated, leaves deposits behind that if left to sit, will break down the passive layer and rust your stainless steel.

3. Chlorides are found nearly everywhere –water, food, and table salt. One of the worst perpetrators of chlorides comes from household and industrial cleaners.

Stainless Steel Care & Prevention of Rust – So what does this all mean if you have burned food crusted onto your stainless steel pans and you cannot use metal scouring pads with that rock hard tap water and an abrasive cleanser? Here’s some guidance.

1. Use the proper tools such as soft cloths and plastic scouring pads. Stainless steel pads can be used but the scrubbing motion must be in the direction of the manufacturers polishing marks.

2. Clean with the polish lines. Most stainless steel has visible polish lines or “grain” so scrub in a motion parallel to them. If a grain cannot be seen, use a soft cloth or plastic scouring pad.

3. Use alkaline, alkaline chlorinated or non-chlorinated cleaners. If you are not sure if your cleaner’s chloride content, ask your chemical supplier and look for an alternative without chlorides. You can use any good commercial detergent or ammonia for routine cleaning. For stubborn stains use cleansers such as “Zud” or “Cameo”. For grease, fatty acids, blood or burnt-on food, use “Easy-off”, De-Grease It, or a similar product. Don’t forget to use heavy duty gloves if any of these products are hard on the hands.

4. Treat your water. Softening water can do much to reduce deposits. Water filters can be installed. Salts in a properly maintained water softener are OK.

5. Keep your food equipment clean and sanitized. Use alkaline, alkaline chlorinated or non-chloride cleaners at recommended strength. Use sanitizers recommended for stainless steel at the correct concentration in sinks and sanitizer buckets. Remember that you cannot sanitize a surface that is not clean. So clean equipment frequently to avoid build-up of stubborn stains.

6. Rinse, rinse, rinse. If chlorinated cleaners are used you must rinse them thoroughly and get them dry. The sooner you remove standing water the better. Oxygen helps maintain the stainless steels’ passivity film. When drying food contact surfaces, the FDA Food Code says it must air dry, so make sure the equipment is in a self draining position.

7. Consider using high heat cooking pan liners such as “PanPals”. The nylon bags come in a multitude of sizes to fit pans and withstand 400 degrees F. That makes clean up of stainless steel pans a breeze and they are a labor saver too.

Bottom Line: Take good care of stainless steel equipment and it will last which saves you the high dollars needed for replacement. Review the standard operating procedures for cleaning process and the products you use to do the job. Ask your chemical supplier or equipment manufacturer for their cleaning and sanitizing recommendations for stainless steel.

‘Til next time,

Lacie Thrall