Cast Iron: Cooking Safely With A Classic

Cast iron pans are a popular kitchen staple, and for good reason. They're durable, versatile, and non-toxic. But are all cast iron pans non-toxic?

Cast iron is made of an alloy that's over 90% iron. It's been used as a reliable cooking surface for well over a thousand years, and there's evidence for its lack of obvious harm. However, cast iron pans can leach iron, a strong pro-oxidant, into food during the cooking process. This means that those genetically at risk for iron overload should be cautious.

Additionally, cast iron safety depends on proper seasoning and maintenance. A well-seasoned pan will be mostly non-stick, but a pan that is newer or less seasoned will leach more iron. Acidic foods, high moisture content, and long cooking times also increase iron leaching.

So, while cast iron pans are generally safe, it's important to use and maintain them properly to minimise any potential risks.

Cast iron pans can leach iron into food during the cooking process

Cast iron pans are generally safe to use but they can leach iron into food during the cooking process. This is because cast iron is made of an alloy that is over 90% iron.

The amount of iron that leaches into food depends on several factors. Firstly, the condition of the cast iron pan. Older, well-seasoned pans will leach less iron than newer pans. Secondly, the type of food being cooked. Acidic foods with a high moisture content, such as tomato sauce, will absorb more iron. Thirdly, the cooking time. The longer food is cooked, the more iron will be absorbed. Finally, the frequency with which the food is mixed will also affect how much iron is absorbed.

While iron is an essential dietary mineral, too much iron can be harmful. Therefore, those who are genetically at risk for iron overload should be cautious when using cast iron pans.

Cast iron pans are not suitable for cooking acidic foods

The acid can also cause the seasoning on a cast-iron pan to break down. The seasoned coating is a layer of polymerized fat that comes from heating fat on the pan's surface, and it can eventually make the pan non-stick. To preserve it, it is recommended to avoid cooking acidic foods in your cast-iron pan for longer than a few minutes or letting acidic foods sit in the pan after cooking.

If you are making a slow-simmered sauce, it is best to use an enamel-lined Dutch oven instead of a cast-iron skillet.

Cast iron pans are not non-stick

Eggs are tough to cook on new cast iron, even Lodge's stuff that comes seasoned from the factory. Lodge pans also typically have the bumpy surface standard with modern cast iron pans, which adds to the difficulty in eggs sticking. The only cast iron pans that can easily cook eggs without a lot of sticking are older pans that were machined smooth. These pans have also been used for many years and maintained with a very strong layer of perfectly smooth seasoning.

Cast iron pans are not anywhere near as non-stick as, say, Teflon, a material so non-stick that we had to develop new technologies just to get it to bond to the bottom of a pan. You cannot dump a load of cold eggs into your cast iron pan, slowly heat it up with no oil, then slide those cooked eggs right back out without a spot left behind. Because you can do that in Teflon.

That said, so long as your cast iron pan is well seasoned and you make sure to pre-heat it well before adding any food, you should have no problems whatsoever with sticking.

Cast iron pans are not hard to maintain

Maintaining cast iron pans is not hard. Here is a step-by-step guide on how to do it:

Cleaning and Care Tips for New Cast Iron Cookware

Cast iron is very strong and with a little effort, you can get your pans into brand-new condition. Seasoning is a hard, protective coating on the pan that's created by rubbing the pan with oil and then heating it. When exposed to heat, each layer of oil transforms into an extremely thin, plastic-like coating. As those layers build up, the pan becomes increasingly protected against rusting and also develops non-stick characteristics.

How to Clean Cast Iron After Cooking

A dirty cast iron pan needs to be cleaned. Contrary to popular belief, you can use a small amount of soap to clean cast iron cookware. Large amounts of soap can strip the seasoning off your pan, but you can easily re-season your pan as needed.

• Wash the cast iron pan well with warm soapy water, wiping it with a kitchen sponge.
• If there are a few stubborn burnt-on bits, you can use the synthetic scrubber on the back of many kitchen sponges, as it's not as harsh as steel wool.
• If, for some reason, you've scorched some nasty stuff into the pan, you can pour salt into it, set it over high heat, then rub the charred gunk out with some paper towels.
• Dry the cast iron pan thoroughly with towels right after washing. Even better, once you've hand-dried the pan as best you can, set it over a high flame. The heat will speed evaporation, driving off any last bit of moisture and guaranteeing that the pan is totally dry.
• Oil lightly and heat the cast iron pan. Rub the pan very lightly all over with an unsaturated cooking fat, like canola, vegetable, or corn oil, making sure to buff away any visible greasiness so that the cast iron almost doesn't look like you've oiled it at all. Then put the pan back over a burner set to high heat, and leave it for a couple of minutes, until the pan is heated through all over and lightly smoking.

How to Clean and Restore a Rusty Cast Iron Pan

Scour the rusty pan with warm, soapy water and steel wool. It's okay to use soap since you are preparing to re-season the cookware. Rinse and hand dry thoroughly. Apply a very thin, even layer of cooking oil to the cookware (inside and out). If you use too much oil, your cookware may become sticky. Place the cookware in the oven upside down on the top rack. Place a large baking sheet or aluminum foil on the bottom rack to catch any excess oil that may drip off the cookware. Bake at 450-500 degrees F for one hour. Allow to cool and repeat as necessary to achieve the classic black patina.

Cast iron pans are not suitable for people with iron overload

Cast iron pans are known to leach iron into food during the cooking process, with studies showing that the amount of iron transferred can vary from 1.7 mg per 100 g to 26 mg per 100 g. Acidic foods, high moisture content, and long cooking durations increase the release of iron significantly.

Therefore, to avoid overdosing on iron, it is best for people with iron overload to avoid using cast iron pans, especially for cooking acidic foods that require long cooking times, such as tomato sauce. Instead, they can opt for alternative cookware materials such as stainless steel, ceramic, or air fryers.

Additionally, people with iron overload should be cautious of their vitamin C intake, as it enhances non-heme iron absorption. They should also limit their alcohol consumption, as it promotes iron absorption and is harmful to the liver.

It is important to consult a healthcare professional for personalized advice and treatment options, which may include dietary changes, medication, or therapeutic phlebotomy to remove excess blood and iron from the body.

Frequently asked questions