When I moved out of my parent’s house, my mother gave me a cast iron skillet as a going-away present, claiming it would last me a lifetime as long as I took proper care of it. So, when I mistakenly went against her instructions to never put my skillet in the dishwasher, I called her in a panic to find out what to do.
She told me to never put cast iron in the dishwasher because the finish is not abraded (it’s rough to the touch), so it requires seasoning and oils to build up a nonstick surface. When a cast iron skillet is placed into the dishwasher, the detergents strip away the oils that keep it from being susceptible to rust.
Why Are You Not Supposed To Wash a Cast Iron Skillet?
A common misconception that comes up a lot is that you aren’t supposed to wash a cast iron skillet at all. This is simply untrue. You can wash your cast iron skillet, but not in the traditional way as you would your regular pots and pans. This is because a cast iron skillet’s chemical composition is 2.5-4.0% carbon, 1-3% silicon, and 93%-96.5% pure iron [1].
Due to the high concentration of iron, it is nearly indestructible, however, it does have one downside to it. It is highly susceptible to oxidation, the process in which a compound experiences a loss of electrons due to direct exposure to oxygen [2].
In the case of metals, such as Iron (Fe), the metal mixes with oxygen and becomes rust (Fe2O3).
This means that if you strip away the protective layer of oils with dishwashing detergents or regular household soaps, and your cast iron skillet comes into contact with water, it can rust, making it completely unusable.
How to Clean Your Cast Iron Skillet After Use?
If you want to clean out your cast iron skillet, you will need to be prepared to get your hands a little dirty. You will also need to jump on it right away after cooking in it, if you want to get the best results.
- Use an old cloth, paper towel, a sponge, or stiff brush as your cleaning apparatus. Do not use steel wool or dish soap.
- Do not let your pan soak. Extended exposure to water can harm the cast iron skillet and cause rust to form if there is a break in your seasoning. Instead, use a little bit of hot water immediately after use and wipe it out. If you wait for your cast iron skillet to cool down before washing, it could warp.
- If there are unwanted food particles that are stuck, use a kosher salt paste or vinegar to help break it apart for removal.
- Dry the skillet with a cloth or towel or place it on the stove on low heat.
- Apply a thin layer of vegetable oil or any other neutral oil on the inside of the skillet. Make sure to cover every square inch of the skillet. Buff any excess oil off with a cloth or paper towel.
- Store in a dry place either in a cabinet or above your stovetop.
How & Where Does This Protective Layer of Oils Come From?
In most cases, when you purchase a cast iron skillet, it will either have an enamel or porcelain coating to it or it won’t come with any coating at all. Due to the porous nature of cast iron skillets, Teflon coatings are rendered useless, as they cannot lay flat across the surface of the cast iron.
If you choose a cast iron skillet that has an enamel or porcelain coating, it will be protected from coming into contact with oxygen while providing a smooth surface across the pan.
This negates the need for “seasoning” the pan with oils, but because of how brittle enamel and porcelain are, they can be chipped away over time, exposing your cast iron skillet to the open air and the potential for rust.
This is where the uncoated cast iron skillet shines, as a well-done seasoning will fill up the peaks and valleys within your pan’s surface, keeping your food from sticking and your skillet from rusting simultaneously.
How to Season Your Cast Iron Skillet?
Properly seasoning your cast iron skillet for the first time is essential to preserving it for a lifetime of use. This will be the only time that you will be required to wash it with soap.
- Preheat the oven to 350-450°F.
- Wash the skillet. Grab a sponge or stiff brush with some warm, soapy water (regular dish soap) and wash the entire surface of the skillet thoroughly. This includes the inside of the skillet, the outside, and the handle.
- Rinse and dry. Rinse off all soap, and then dry the entirety of the skillet as much as possible. You want it to be “bone” dry.
- Add oil. The most commonly recommended are unsaturated cooking oils like vegetable oil or melted shortening. You should use a neutral fat but leave out flaxseed oil as the option, as it tends to flake.
- Spread the oil around. Coat the entire skillet using a clean cloth or paper towel. You want the oil to cover every square inch of the skillet, including the exterior (bottom, sides, handle). If you miss any portions of the skillet, you are opening it up to rust which can spread quickly across the entire pan.
- Bake the skillet. Place the skillet upside down on your oven’s center rack with a sheet of aluminum foil beneath it to catch any oil drips. Bake for 1 hour.
- Let it cool down before storing it. Take it out of the oven and allow it to cool right down. At this point, you can choose to give it one last wipe with a thin layer of oil or to just store it away in a cabinet or above your stovetop.
What To Do If You Put a Cast Iron Skillet in the Dishwasher?
If you (like me) went against your mother’s instructions and put your cast iron skillet in the dishwasher, you may be able to save it but it will require a lot of work on your part.
Unfortunately, if your cast iron skillet is a family heirloom or a hand-me-down, it may never recover the protective coating it once previously had, nor will it regain the associated flavor that goes along with a well-used cast iron skillet. This is because a good coating takes years to build up.
The first thing to take into account is that rust can start to form quickly, so you will need to scrub the skillet hard to remove it all. This step is the most lengthy of the process but is arguably the most important, as the entire skillet needs to be rust free. You will need a lot of elbow grease to get this step done and some hot water.
Next, follow the steps above for seasoning your skillet from first to last, straight away, as any time left in between is time for more rust to form. Take extra care in making sure that the entire skillet is covered in oil, as even a lightly used skillet will have scratches and scars that will likely result in an uneven coating.
Once this is done, there’s nothing more you can do aside from continuing to use the skillet, as you would normally. You will need to rebuild the protective layers that have been stripped away.
Please note: while it is possible to save your cast iron skillet after being placed in the dishwasher, it is not a guarantee. The combination of the hot water, the dishwasher detergent, and the scrubbing action is going to completely remove any seasoning your pan had, reverting it to a raw, unprocessed state.
This is going to make it extremely hard to recover a semblance of its original functionality. Bear this in mind as it is likely that you will need to purchase a new cast iron skillet.
Is It Ok To Use Soap on a Cast Iron Skillet?
You should never use soap or detergents on your cast iron skillet, unless it has never been seasoned before or used. When detergents or soaps are used on a seasoned skillet, they will break down the oils that you have carefully cooked into the iron over its years of use.
The nifty thing with cast iron skillets is that the seasoning gets better over time and with frequency of use, so using any soap on it will destroy the hard-won treatment you’ve built up.
Wrapping It Up
A quality cast iron skillet is an essential tool in any cook’s arsenal, but must be cared for accordingly. As long as you remember to clean it properly, keep it seasoned and away from soap and dishwashers, a cast iron skillet can last through several generations while improving with age.