Me and My Cast Iron
Will Soap Really Ruin My Cast Iron?
Some cast iron purists say soap is a sin. So will it destroy your prized pans’ hard-earned seasoning? We asked the experts.
By Kimberly Holland
September 03, 2020
Caring for a cast iron pan is unlike any other task in the kitchen. You don’t have to worry about seasoning other skillets, and most dishes won’t suffer from a rinse in the sink or even in the dishwasher if you’re in a pinch.
But cast iron pans and skillets aren’t that forgiving. In fact, if you’ve ever purchased a cast iron skillet or inherited one from a family member, you’ve probably been on the receiving end of dire warnings: never wash your pan.
With all due apologies to grandmothers everywhere who still believe this, we’re here to tell you that’s not entirely true. You can in fact wash your cast iron pans, and you can even use soap. But if you do, you’ll need to take a few extra steps to care for the pan so you don’t have any rusty regrets later.
Will Soap Strip Seasoning Off Cast Iron Pans?
No, most soaps today aren’t powerful enough to remove baked-on seasoning, but a little time travel explains where this urban legend comes from.
Decades ago, soaps were made with lye and vinegar, and they were too harsh for use on cast iron pans. They would indeed strip away oil and could remove seasoning. But today’s soaps, especially ones that are made with eco-friendly solutions, are often too mild to remove seasoning.
Joanna Rosenberg, chief marketing officer at Staub, says what is more likely to happen is that washing a brand-new pan with soap could remove the first layers of oil that were applied in the factory.
“Most cast iron today comes pre-seasoned, ready to use right out of the box, but the durability of that coating is not consistent,” she says. “If you put a brand-new pan in the sink with a scrubbing sponge and dish soap, you probably will remove that seasoning.”
That’s why, she adds, if you want to wash your brand-new pan, you should go ahead and season it again before cooking with it.
Soap doesn’t remove seasoning, but it can remove some oil.
Cast iron is beloved for its natural non-stick quality. This is built up over months and years of use, as a layer of seasoning develops on the pan’s surface. Seasoning is a prized cast iron element, and many people will seek out old pans at thrift stores and estate sales so they can have a pan that’s been lovingly seasoned for decades.
But oil isn’t responsible for that well-seasoned pan’s non-stick surface. Well, not oil alone. Instead, a process called polymerization is the reason cast iron pans become increasingly nonstick with use. Polymerized oil combines with the porous surface of the pan to create a harder, smoother surface on top of the skillet. It takes more than soap and water to remove this seasoning, but soap can remove excess oil that’s left on the surface of the pan after cooking. This is oil you’d probably wipe away with a paper towel anyway.
Rosenberg says, “The seasoning that’s baked on there, from lots of high temperature cooking, that has formed a bond with the coating and the pan itself, even if you’re going at it with soap and a sponge and elbow grease, that is unlikely to come off.”
So should I use soap and wash my cast iron pans?
While many cast iron purists will tell you to simply wipe the pan out with a towel and store it, that’s a hard pill to swallow from some cooks. After all, there’s likely food residue and oil still on the skillet.
So you can use soap and water to wash your cast iron skillets — even Lodge, an iconic cast iron brand, says so — but the truth is, there is a better way to clean them:
- Loosen food and debris with a hard-bristle brush (like this $12 Natural Fiber Bristle Pot Brush).
- Use a chainmail scrubber ($22; Amazon) to remove baked-on bits of food that need a little extra power, and use the scrubber to also clean the outside of the pan. Rinse, check for leftover bits, and scrub some more until they’re gone.
- Dry the pan well, then place it on a stove eye and heat it over medium-low until the water has all evaporated. Turn the eye off.
- Pour 1/2 teaspoon of high-temp oil (like flaxseed, vegetable, or canola) into the pan, and use a paper towel to cover the surface of the pan, inside and out.
- Let the pan cool completely, then wipe away excess oil. Store it until you’re ready to cook again.
You can also use kosher salt to clean a cast-iron skillet. This method works better in pans that don’t have any baked-on residue that needs to be removed, but the salt can absorb any excess oil lingering on the pan’s surface.
- Pour 1 cup kosher salt into a still-warm cast iron skillet. Use a paper towel or folded kitchen towel to scrub the pan with the salt until the pan appears clean. (The salt will be nearly black.)
- Rinse out the pan, and dry it.
- Heat the pan over a stove eye on medium-low heat to remove excess water. Turn the eye off.
- Pour 1/2 teaspoon of high-temp oil (like flaxseed, vegetable, or canola) into the pan. Use a paper towel to run the oil over the surface of the pan, inside and out.
- Let cool completely. Wipe away excess oil, and store the pan.
How to Clean Cast Iron With Soap
If you do decide to use soap to clean your cast iron pans, you’ll just want to take a few steps to make sure it’s ready to use the next time you’re cooking. Never let the pan soak in water, and immediately dry it after washing. Water can quickly cause rust.
- Use a hard-bristle brush or the scrubbing side of a sponge to loosen up food and debris.
- Pour a bit of mild dish soap into the pan, and clean the brush or sponge. Rinse the pan, and dry it immediately.
- Heat the pan over a stove eye on medium-low heat to remove any water. Turn the eye off.
- Pour 1/2 teaspoon high-temp oil (like flaxseed, vegetable, or canola) into the pan. Use a paper towel to spread the oil across the pan, inside and out.
- Let cool completely. Wipe away excess oil, and store the pan.
If you have stuck-on bits that won’t come off, you can loosen them up by adding some water to the pan and heating it over medium heat for three to five minutes. Then, use a hard-bristle brush to scrape the bits loose.
Cleaning Cast Iron vs. Enamel-Coated Cast Iron
If you love the high-temperature, effortless functionality of cast iron but loathe the idea of not really being able to wash your pan (listen, we get it), there is an alternative that may be more palatable: enamel-coated cast iron.
Classic non-coated cast iron, like this Lodge 12-inch Cast Iron Skillet, will require the work of cleaning, dry, and seasoning for continuous care. That is a level of dedication many of us are willing to give to our cast iron pans, at least occasionally. Lodge even sells a five-piece Cast Iron Care Kit ($18; Amazon) that includes a hard-bristle brush, scrubber, and seasoning spray to make upkeep easier.
But enamel-coated cast iron is highly durable and can be used just as non-coated cast iron: on the stove, in the oven, on a grill, over a fire. Popular brands include Le Creuset, Staub, and Emile Henry.
Staub’s enamel-coated cast iron pans are often confused with non-coated cast iron because the enamel is black and made with a textured finish that feels nearly identical to other cast iron pans. “But you can clean it anyway you like,” Rosenberg says. You can even put it in the dishwasher, which is something you cannot do with non-coated cast iron.
However, enamel-coated cast iron is often pricier than non-coated, so you need to pick which priority is more important to you. If you prefer a pan that’s easy to clean and doesn’t require loads of extra care, the enamel-coated pans are right for you. But if you don’t mind the upkeep and care of cast iron (and do like the smaller price tag), non-coated pans will be your pick. Both pans are highly durable, and if cared for, will last decades, or even a whole lifetime.