Stainless Steel Roasting Pan: Rust-Proof?

Stainless steel roasting pans can rust, despite the name. Rust occurs when metal is exposed to a combination of water and oxygen, and pans can be more prone to rusting in humid climates. To prevent rust, pans should be washed with mild soap and thoroughly dried after use.

Why does stainless steel rust?

Stainless steel is an alloy made from a combination of iron ore, chromium, silicon, nickel, carbon, nitrogen, and manganese. The chromium in the alloy reacts with the oxygen in the air to form a protective layer that makes stainless steel highly resistant to corrosion and rust. This protective layer can be damaged by harsh environments, mechanical damage such as scratches, and exposure to certain chemicals, water, and heat.

When the protective layer is damaged, water can settle into the openings of the exposed metal, causing rust to form. The chromium oxide layer can also be worn down over time, and if there is not enough chromium left in the alloy, the metal will begin to rust.

Therefore, stainless steel is not completely rust-proof, but "stain-less", meaning that it stains less than other metals. The chances of stainless steel rusting are slim, but it can happen if the metal is not cared for properly or exposed to certain elements.

To prevent rust from forming on stainless steel, it is important to clean and polish the metal regularly. This will help to remove any water or impurities from the surface and maintain the integrity of the protective chromium oxide layer. It is also recommended to dry stainless steel with a towel or cloth immediately after washing, rather than letting it air dry, as this can lead to water spots and rust.

If rust does occur, it can be removed using various methods, including household ingredients such as baking soda, vinegar, and lemon, or store-bought rust removal products.

How to prevent rust on stainless steel roasting pans

Stainless steel roasting pans can indeed rust, despite the name. Rust occurs when metal is exposed to a combination of water and oxygen, and stainless steel contains the alloy chromium, which oxidises and creates a natural protective coating on the metal. If this coating is scratched, water can settle into the openings of the exposed metal, causing rust.

Proper Cleaning and Polishing

Stainless steel will rust if not cleaned and polished properly. Clean the pan with mild soap and thoroughly dry it with a microfiber towel after each use. This will prevent dried and burnt food from building up and provide a clean surface for polishing. Polishing is important for keeping the chromium oxide coating intact, so rust will not form.

Avoid Air Drying

Do not let the metal air dry. Instead, dry the pan with a microfiber towel right after washing to remove any water from the pan.

Store in a Cool, Dry, Dark Place

Ideally, store your roasting pan in a cool, dry, and dark place. Heat and humidity can encourage the buildup of rust. Ensure the pan is completely dry before storing, as proper drying is the best way to prevent rusting.

Apply a Coating of Rust-Proof Primer

If you use your roasting pan occasionally, apply a coating of rust-proof primer to add a protective layer and reduce the chances of rust.

Buy High-Quality Stainless Steel

Invest in high-quality stainless steel cookware, ideally made from 18/10 or 304 stainless steel. These have a higher chromium percentage, making them tougher and more corrosion-proof.

Place a Protective Layer When Stacking

If you stack your pans in a cupboard, place a dish towel, trivet, or other protective layer between each pan to prevent scratching.

How to remove rust from stainless steel roasting pans

Although the chances of stainless steel rusting are slim, it is not impossible. If your stainless steel roasting pan has developed rust, it can be easily removed. Here are some methods to help you restore your pan to its former glory:

Using Baking Soda

Rinse the pan with water and cover it with baking soda. Let the baking soda sit for at least 30 minutes, and then use a scouring pad, soft-bristled brush, or the coarse side of a sponge to scrub the rust away. Finally, wash the pan with soap and water and dry it with a towel.

Using Vinegar

Spray or wet the pan with water and wipe it clean with a cloth. Then, spray a mixture of equal parts water and vinegar onto the stainless steel. Let the mixture sit for a few minutes, and then use a scouring pad to lightly scrub along the grain of the steel to remove the rust. Wash the pan with soap and water, and dry it with a towel.

Using Coarse Salt and Potato or Lemon

Sprinkle coarse sea salt onto the rusty spots and scrub it with a cut potato or lemon. The oxalic acid in potatoes and the citric acid in lemons help dissolve rust. Rinse the pan with water and dry it with a towel.

Using Oxalic Acid

Apply a cleaner containing oxalic acid, such as Bar Keepers Friend, to the affected area. Rub the cleaner in the direction of the metal grain lines using a soft, slightly damp sponge. Rinse and dry the pan.

Preventing Rust on Stainless Steel Roasting Pans

To prevent rust from forming on your stainless steel roasting pan, always dry the pan immediately after washing it. Use a soft dish towel or microfiber cloth, and avoid air-drying as this can lead to water spots and rust. If you stack your pans, place a dish towel or pan protector between them to prevent scratching. Additionally, always wash your pan with mild soap and water after use, and ensure it is thoroughly dried.

Is it harmful to eat from a rusty pan?

It's best not to eat from a rusty pan. While consuming a small amount of rust is unlikely to harm your health, rust is not food-safe and should not be ingested.

Rust is a reddish or yellowy-brown coating made of iron oxide that can form on steel or iron when exposed to a combination of water and oxygen. It is a naturally occurring chemical process that results in the decomposition of steel and iron.

According to the United States Department of Agriculture, rust is not food-safe and shouldn't be ingested. While it is unlikely that a rusty pan will harm you, there is a chance that some of the rust will end up in your food. Even in small quantities, it is best to avoid consuming rust.

Additionally, rust can affect the flavour of your food and make cooking more difficult. It can also cause food to stick to the pan, making it harder to flip pancakes or sear steaks.

If your pan has rusted, it is best to clean and restore it before using it again. There are several methods to remove rust from a pan, including using baking soda, vinegar, or steel wool. It is also important to properly maintain your pans to prevent rust from forming. This includes drying your pans immediately after washing, polishing them, and seasoning cast-iron pans before use.

How does humidity affect the likelihood of rust?

Humidity plays a significant role in the formation of rust. Rust occurs when metal is exposed to a combination of water and oxygen, and in humid climates, there is more moisture in the air, increasing the likelihood of rust forming on your cookware. Metal corrodes at a much faster rate under humid conditions as the moisture-saturated air reacts with oxygen and electrons on the metal's surface.

The amount of moisture in the air is crucial; when it reaches a critical humidity level, water no longer evaporates or gets absorbed from the atmosphere. This typically happens at 80% relative humidity. However, it's not just the humidity that causes corrosion; it's the change in temperature coupled with a significant increase in humidity that leads to moisture formation on metal surfaces.

For example, when the temperature rises, humidity levels also tend to increase. Every 50°F (10°C) increase in temperature can double corrosion activity. Additionally, when a surface cools below the surrounding air temperature, moisture will condense on it, which is common in manufacturing facilities overnight.

To prevent rust from forming on your stainless steel roasting pan, it is essential to keep it dry. Wash the pan with mild soap and thoroughly dry it with a soft dish towel or microfiber cloth after each use. Polishing the pan can also help create a protective barrier against rust.

Frequently asked questions