Cleaning Cast Iron: Removing Carbon, Restoring Pans

Cast iron pans are durable, non-stick, and retain heat well. However, carbon buildup can be an issue, and while it's not harmful, it can look unpleasant and affect the taste of your food. The good news is that it's not too hard to remove. You can use salt, a stiff brush, or an oven cleaner to scrub away the carbon, and then reseason the pan. Soaking the pan in water before scrubbing can also help. Remember to always dry your cast iron pan thoroughly and keep the surface seasoned to prevent rust.

Use salt to scrub the pan

Salt is an effective and straightforward way to scrub off carbon buildup from your cast iron pan. Here is a step-by-step guide:

Step 1: Prepare the Salt Scrub

Sprinkle an even layer of salt on the inside of the pan. The amount of salt will depend on the size of your pan, but generally, about 1/4 cup of salt should be sufficient. You can also add just enough water to create a paste-like consistency.

Step 2: Scrub the Pan

Using a flat-edged kitchen utensil, such as a spatula, vigorously push the salt around the pan. Make sure to cover the entire inner surface, including the corners and edges, as carbon can build up in those areas as well. The salt will start to turn grey or black as it absorbs the carbon. Continue scrubbing until most of the carbon has been lifted.

Step 3: Rinse and Remove Remaining Carbon

Once you have scrubbed the pan with salt, rinse it with water to remove the salt and loosened carbon. You can then use a wire scrub brush to address any remaining carbon residue. Be thorough in this step to ensure all carbon is removed.

Step 4: Wash and Dry the Pan

After removing the carbon, wash the pan with mild soapy water to eliminate any remaining grease or salt residue. Use a soft sponge or cloth to avoid damaging the pan's surface. Once washed, dry the pan thoroughly with clean paper towels or a dishcloth.

Step 5: Re-season the Pan

Cast iron pans are typically seasoned with oil to create a non-stick surface and protect against rust. After removing the carbon and cleaning the pan, it is essential to re-season it. Coat the pan with a light layer of oil, place it in an oven preheated to 500°F (or as high as possible) for about an hour. Turn off the oven and let the pan cool inside before removing it. Your pan is now ready to be used again!

Using salt to scrub your cast iron pan is a simple and effective method to remove carbon buildup. Just make sure to be thorough in your scrubbing and follow up with proper cleaning and re-seasoning to maintain the pan's quality.

Soak the pan in water

Soaking your cast iron pan in water is an effective way to remove carbon buildup. Before you begin, check that your pan does not have rust on it, as this will require a different cleaning method. If your pan is rust-free, start by filling your sink with hot water and submerging the pan for about an hour. If the carbon buildup is particularly heavy, you can leave it to soak for longer.

Once your pan has soaked, remove it from the water and use a stiff brush to scrub the surface. You can add a small amount of dish soap to your brush to help break down the carbon. However, some experts advise against using soap on cast iron, so this is up to your discretion. If you do choose to use soap, be sure to rinse the pan thoroughly with hot water afterward to remove any soapy residue.

After scrubbing, dry your pan off with a towel. It is important to ensure that the pan is completely dry before moving on to the next step. To do this, place the pan on high heat on your stove until any remaining moisture evaporates.

Finally, season the pan with a light coat of oil to restore its non-stick properties. This will also help to prevent future carbon buildup. Your pan is now ready to be used again!

Use a stiff brush to scrub the pan

Using a stiff brush to scrub your cast iron pan is a great way to remove carbon buildup without too much effort. The first step is to ensure you have the right tools for the job. You'll need a stiff brush, such as the Full Circle Tenacious C Cast Iron Brush, which has bristles that are a bit more stiff and can handle a decent amount of burnt-on bits without disturbing the seasoning.

Next, you'll want to prepare the pan for scrubbing. If there are stuck-on bits of food, you can add about a quarter cup of kosher salt and a few drops of warm water to the pan while it's still warm. Use a wooden spatula or a scrub brush to gently remove the gunk. The salt will dissolve as you scrub and won't damage the seasoning.

Now it's time to scrub! Take your stiff brush and scrub the surface of the pan with a small amount of dish soap. You can also use a small amount of soap to clean cast iron, as it won't hurt the pan as long as it's well-seasoned. Be sure to scrub gently so as not to damage the seasoning.

Once you've scrubbed the pan, rinse it clean and dry it off with a towel. You can also put it in the oven at a low temperature to ensure all the moisture evaporates. It's important to get the pan completely dry before storing it to prevent rust.

Finally, you'll want to season the pan after scrubbing. Apply a light coat of oil, such as canola or vegetable oil, and rub it all over the inside and outside of the pan with a paper towel or clean rag. This will help protect the pan and keep it in good condition for future use.

Reseason the pan after cleaning

Reseasoning a cast-iron pan is a straightforward process that will help to prevent rust and ensure an even cooking surface. It is recommended that you reseason your pan a couple of times a year or whenever you notice the surface drying up or rusting.

To reseason your pan, start by scrubbing it with hot, soapy water. You can use a nylon scrub brush or fine steel wool to remove any rust. Once the pan is clean, dry it thoroughly inside and out.

Next, coat the pan with a thin layer of oil, such as safflower, canola, or vegetable oil. You can also use melted shortening. Soak a paper towel in the oil and coat the inside, outside, and handle of the pan. Be sure to use just enough oil so that the pan has a nice, even coating without being slippery.

Now, you're ready to bake your cast-iron pan. Preheat your oven to between 350-500˚F. Place the pan upside down on the middle rack of the oven and put a sheet of aluminum foil on the lower shelf to catch any drips. Bake the pan for about an hour. You may need to repeat this process a few times to achieve the desired semi-gloss finish.

After an hour, turn off the oven and let the pan cool completely inside. When the pan is cool, wipe away any excess oil with a paper towel. From now on, wash your pan with hot water only (no soap) and dry it thoroughly after each use.

Avoid overheating the pan

To avoid overheating your cast iron pan, it is important to understand the concept of thermal shock. Thermal shock is the number one enemy of cast iron pans. When a cast iron pan is heated, the metal expands slightly, this is known as thermal expansion. This process can occur in two ways: firstly, by suddenly and repeatedly exposing a cold cast iron pan to high or extreme heat, and secondly, by immersing a hot cast iron pan in freezing water immediately after removing it from the stove or oven.

In both cases, the expansion process of the metal is forced to occur faster than it should, which can have disastrous results for your pan. To avoid this, it is recommended to start with a low heat level and then gradually adjust the temperature. By using your cast iron pan this way, you can maintain its thermal efficiency.

Overheating a cast iron pan can cause irreversible bumps, dents, and warps. A slightly warped pan can still be used on a gas stove or in the oven, but its efficiency will be significantly reduced. Warping can occur when an empty pan is left on a hot burner, even for a short period. With nothing in the pan to absorb and distribute the heat, the metal in the centre of the pan expands faster than the surrounding areas, causing the once smooth surface to become concave or convex.

Similar damage can be caused by rapid cooling, such as placing a hot pan in a sink full of water. Using a deformed pan will result in uneven cooking, as liquids and cooking fats will either stagnate in the centre or move to the edges of the pan, affecting the final cooking result and flavours.

Cast iron pans are incredibly durable and can withstand more heat than other types of cookware. However, overheating can damage the pan and cause food to stick. It is recommended to only cook at medium to moderate temperatures when using cast iron, as it holds heat very efficiently.

If you accidentally overheat your cast iron pan, reduce the heat and allow it to cool to the proper temperature before adding your ingredients and continuing cooking.

Frequently asked questions