Should You Use Soap on a Cast Iron Pan?
If you’ve ever wondered whether it’s safe to scrub your cast iron pan with soap, you might have been met with strong resistance from cast iron enthusiasts. They might even threaten to give you a firm whack with their skillet for suggesting such a thing! But according to Sean O’Keefe, a professor in the Department of Food Science and Technology at Virginia Tech, it’s time to revisit this old-school myth and clarify some do’s and don’ts for cast iron care.
Cast iron skillets are beloved for their durability and the fact that they don’t release harmful chemicals into food, even after years of use.
“Cast iron is one of those things that’s largely indestructible,” O’Keefe explains.
However, unlike stainless steel, cast iron can rust. Stainless steel contains chromium, which forms a protective chromium oxide layer on its surface, preventing rust. Bare cast iron, on the other hand, rusts quickly if not properly cared for. This is why it’s crucial to “season” your cast iron pan thoroughly before you start cooking with it.
There’s also a common belief that you shouldn’t use cast iron to cook acidic foods, as it can damage the seasoned layer. According to O’Keefe, this is only partially true.
“You can definitely use a cast iron pan to cook, but if you leave acidic foods in it for a long time, they can start to break down the protective layer,” O’Keefe says. “For example, if I’m frying something with tomatoes or another acidic ingredient, I’m not too concerned. But I wouldn’t recommend using a cast iron pot for making spaghetti sauce over a long period.”
One of the most enduring pieces of advice passed down from experienced cast iron users is to never use soap on your pan. O’Keefe notes that while this was true decades ago, it’s not as relevant today because modern dish soaps typically don’t contain lye, which was a common ingredient in older soaps.
“If you see soap causing rust on your pan, it’s a sign that it wasn’t properly seasoned to begin with,” O’Keefe explains. He assures that modern soap won’t strip away the protective layer of a well-seasoned pan.
So, are cast iron skillets dishwasher-safe? The answer is yes, but with a caveat: they should be placed in the dishwasher without soap pods. O’Keefe points out that the ingredients in soap pods can be too harsh on cast iron.
“Dishwasher detergents are much more aggressive than regular dish soap, and they can be damaging to the surface of cast iron pans,” he says.
A water-only cycle in the dishwasher won’t harm your pan, but O’Keefe warns against letting the pan stay wet for too long if the dishwasher doesn’t dry it thoroughly.
Cast iron skillets are more than just cooking tools; they’re often treasured family heirlooms. O’Keefe humorously notes that they can even cause family disputes.
“We see these things handed down through generations, and people can get pretty protective over them. It’s like my sister got my mom’s sewing machine, but there’s no way she’s getting my mom’s cast iron,” O’Keefe jokes.
Tips for Caring for Cast Iron, According to O’Keefe:
- Season Your Pan Properly: Before its first use, apply a thin, even layer of fat or oil on the pan’s surface, inside and out. Place the pan upside down in the oven at 450°F for 1 hour to polymerize the oil. Repeat this process two to three times to create a strong, impermeable layer of oxidized oil. Some pans come pre-seasoned, so check before you start.
- Clean After Each Use: Rinse your pan with warm water, and use soap if necessary. Dry the pan thoroughly and rub it with a thin layer of oil to maintain the seasoning.
- Choose the Right Oil for Seasoning: Use an oil with a high polyunsaturated fat content, like soybean or flaxseed oil, which will create a durable layer. Oils like coconut oil are less effective for this purpose.
- Preheat Before Cooking: Cast iron heats unevenly, so make sure the entire surface is hot before adding food.
- Handle with Care: Cast iron retains heat longer and gets hotter than other types of pans, so be cautious when handling.
- Use Appropriate Utensils: While wood utensils are ideal, you can use metal ones as long as you don’t scrape or dig into the pan’s surface, which could damage the seasoning layer.