Restore Stainless Steel: Removing Pits From Pans

Stainless steel is a durable and versatile material that is well-loved by professional chefs and home cooks alike. However, even the highest-quality stainless steel cookware is not completely immune to damage and staining. One of the most common issues with stainless steel pans is pitting, which refers to small pock-like marks or dull-looking dots on the surface of the pan. This damage is caused by a breakdown of the protective layer of chromium oxide on the pan's surface due to exposure to chlorides found in salt and other cleaning products. While pitted stainless steel cannot be repaired, there are several strategies you can employ to prevent pitting and keep your pans in good condition. Firstly, it is important to avoid using bleach, abrasive cleaners, and steel wool when cleaning your pans, as these can damage the protective layer and make the pan more susceptible to pitting. Additionally, it is recommended to add salt to water only after it has come to a boil, as this prevents salt from settling at the bottom of the pan and causing pitting. By following these simple tips, you can help extend the life of your stainless steel pans and maintain their shiny, spot-free finish.

What is pitting?

Pitting is an erosion of the surface of stainless steel cookware. It occurs in the presence of chlorides, like salt, and can be caused by adding salt to water before it comes to a boil. Sodium chloride, which is an element found in cooking salt, can settle to the bottom of the pan and cause pitting. Sodium hypochlorite, the active ingredient in bleach, also leads to pitting.

Pitting can also be caused by undissolved salt added to a stainless steel pot or by water boiled dry, as the chloride in the salt can attack the passive layer of chromium oxide, leaving pockmarks where it removes the oxide.

Chlorine and chloride salts are responsible for metal pitting on stainless steel. They cause a breakdown of the passive chromium oxide layer on the metal, and once the pitting starts, it can spread rapidly. The Stainless Steel Information Center advises that several substances that contain chlorides can cause pitting, which can form deep crevices and even spread all the way through the metal.

Pitting cannot be repaired, so the best strategy is to avoid it in the first place. This may involve modifying your cooking routine and cleaning habits. For example, salt should only be added to water once it has come to a boil, as at this temperature, there isn't enough oxygen in the water for the reaction to occur. It is also important to avoid the use of bleach and other cleaners containing chlorine when cleaning stainless steel cookware.

What causes pitting?

Pitting on stainless steel pans is caused by the breakdown of the passive chromium oxide layer on the metal. This layer is responsible for preventing the metal from rusting. When this layer breaks down, it exposes the metal to corrosion, leading to the formation of pits or small, pock-like marks on the surface.

The most common culprit of pitting is sodium chloride, which is an element found in cooking salt. If you add salt to your water before it reaches a boil, some of the salt will settle to the bottom of the pan, causing pitting to occur. This is because the salt is not given enough time to dissolve and distribute evenly in the water.

Additionally, sodium hypochlorite, the active ingredient in bleach, can also lead to pitting. When these elements come into contact with stainless steel cookware, they can cause the protective layer of chromium oxide to break down, resulting in the formation of pits.

While pitting may not affect the performance of your cookware, it is important to note that once it starts, it can spread rapidly and may not be long before the cookware develops pinholes and becomes unusable. Therefore, it is crucial to take preventive measures, such as adding salt only after the water has boiled or avoiding the use of bleach and other cleaners containing chlorine when cleaning stainless steel cookware.

How to prevent pitting?

Pitting is a form of damage that occurs on the surface of stainless steel pans. It is caused by a reaction between the pan's surface and chlorine or chloride salts, which are commonly found in cooking salt and bleach. This reaction causes a breakdown of the protective chromium oxide layer on the metal, leading to the formation of small, dull-looking dots or pits on the pan's surface. While pitting does not affect the performance of the cookware, it can spread rapidly and render the pan unusable if left unchecked. Here are some ways to prevent pitting:

• Wait to add salt to water: The best way to prevent pitting is to add salt only after the water has come to a boil. This prevents the salt from settling at the bottom of the pan and reacting with the metal surface.
• Avoid cold pans: Ensure that both the pan and the ingredients are hot before adding salt to your dish. This helps the salt melt on contact, reducing the risk of pitting.
• Salt after plating: If you want to finish your dish with salt, it is best to do so after plating the food rather than adding salt to the pan.
• Avoid abrasive cleaners: Do not use straight bleach or abrasive cleaners that contain bleach to clean your stainless steel pans. Opt for mild dish soap or powdered cleaners instead.
• Handwash immediately: Leaving salty water or food residue in the pans for extended periods can contribute to pitting. It is recommended to handwash the pans immediately after use or at least rinse them out to remove any salty residue.
• Avoid dishwasher use: The intense soaps used in dishwashers can also cause pitting.
• Dry pans after washing: Letting water droplets sit on the pan can lead to chalky, white spots called calcium deposits. Dry your pans right after washing to prevent this.

By following these simple guidelines, you can effectively prevent pitting and maintain the condition of your stainless steel pans.

How to remove pitting?

Pitting is an erosion of the surface of stainless steel pans, which occurs in the presence of chlorides, like salt. It is caused by chlorine and chloride found in salt, which leads to the breakdown of the protective layer of chromium oxide on the pan's surface. Once the pitting starts, it can spread rapidly and cause deep crevices, even spreading all the way through the metal. It is important to note that pitted stainless steel cannot be repaired.

To remove pitting from stainless steel pans, follow these steps:

Identify the Cause:

Start by identifying the cause of the pitting. The most common culprits are sodium chloride, which is found in table salt, and sodium hypochlorite, the active ingredient in chlorine bleach. Even filling a stainless steel pot with salty water can cause pitting, especially if it is done repeatedly.

Avoid Further Damage:

Once you have identified the cause, take steps to avoid further damage. This may include modifying your cooking routine and cleaning habits. For example, add salt only after the water has come to a boil, as at that temperature, there is not enough oxygen in the water for the pitting reaction to occur. Also, avoid using bleach and other cleaners containing chlorine when cleaning your stainless steel pans.

Clean the Pans:

To remove the pitting, you can try using commercial cleaners specifically designed for stainless steel, such as Bar Keepers Friend. These cleaners can help remove the pitting without damaging the pan's surface. Follow the manufacturer's instructions for best results.

Prevent Future Pitting:

The best strategy to deal with pitting is to prevent it from occurring in the first place. This includes avoiding the use of salt until the water has boiled and being cautious when using cleaners with chlorine. Additionally, always dry your pans immediately after washing, as water droplets can lead to chalky, white spots called calcium deposits.

Consider Replacement:

If the pitting is severe and cannot be removed, you may need to consider replacing your stainless steel pans. Heavily pitted pans may leach more metals into your food, so it is important to err on the side of caution.

How to avoid pitting?

Pitting is caused by the breakdown of the protective layer of chromium oxide on the surface of stainless steel pans. This is usually caused by the reaction of chlorine and chloride found in salt with the chromium oxide layer. Therefore, to avoid pitting, it is important to prevent this reaction from occurring. Here are some ways to do so:

• Avoid using salt in your stainless steel pans. If you need to use salt, only add it to water once it has started boiling. This way, the salt dissolves in the hot water and does not settle at the bottom of the pan, preventing the reaction with the chromium oxide layer.
• Avoid using bleach or other cleaners containing chlorine, such as muriatic acid, when cleaning your stainless steel pans. These chemicals can damage the chromium oxide layer and cause pitting.
• Dry your pans immediately after washing them. Leaving water droplets on the pans can lead to the formation of chalky, white spots called calcium deposits, which can be difficult to remove.
• Avoid using abrasive cleaners and harsh brushes that may cause deep scratches in the surface of your pans. This includes bleach-based cleaners, steel wool, and oven cleaners. These can create small scratches that expose the steel underneath, making it more susceptible to corrosion and pitting.
• If you need to remove stains from your pans, use a non-abrasive cloth or sponge and a mild cleaner. A paste made of baking soda and water or a specialised stainless steel cleaner, such as Bar Keepers Friend®, can be effective in removing stains without damaging the surface.
• Avoid filling your stainless steel pans with salty water for prolonged periods. Even if you don't heat the water, leaving salty water in the pans can cause pitting over time.
• If you need to soak your pans, rinse them first to remove any salty residue, then fill them with plain water to dilute any remaining ingredients.

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