First, the black specks you see coming off into your food are not harmful. They are most likely carbon deposits. This happens due to overheating of fats and oils. Using an oil with a low smoke point will carbonize at high temperatures and cause residue from the pores of your pan to rub off onto your food.
The black residue on a cast iron skillet isn't harmful; it's just a part of cooking with a cast iron pan. A black seasoned coating shouldn't rub off easily or affect the food, as it should form a useful non-stick surface for cooking. If residue starts to build up, however, this can affect your cooking.
It's just chunks of fat/oil with bits of black rust, or black oxide. The solution is to either stop using the pan to cook scrambled eggs, or strip the pan down to the cast iron and re-season it.
*Once the food is prepared in an iron vessel, never let it sit in it. Immediately transfer it to a bowl. This helps in preventing the food from turning black. “It is very important to season iron tawa as the batter will stick on an unseasoned tawa,” the chef said.
While many things may come into play (some say that using too much oil, such as olive oil, can cause dishes like chicken breast to turn dark- or that the food is too close to the burning coals), the main reason your food may turn a dark, soot-like color is dirty air shutters and burners.
Cast iron pans can leach a sizeable amount of iron into your food, exceeding dietary intake in some cases. Acidic foods will contribute to much more leaching while an old, heavily-seasoned pan will leach much less iron than a newer one.
You'll use less oil, avoid harmful chemicals, and get a little extra iron in your diet.
So, Is Cooking in Cast Iron Healthier than Cooking in Other Pans? In short: No. You'd have to be mouse-sized to see quantifiable health benefits from mineral intake exclusively with cast iron. Because mineral transfer happens at such a small scale, it's safe to say that cast iron is not any healthier than other pans.
Can cast iron cause iron toxicity? Only people with hemochromatosis are at risk of iron toxicity from cast iron cookware. Even then, the risk is low, since a new, well-seasoned cast iron pan only leaches about five milligrams of iron per cup of food. Older pans will leach less cast iron.
As a general rule, you want to keep your cast-iron pan very dry to preserve its seasoning and prevent rust. The acids in food left in the pan will break down the seasoning, plus storing food in the pan for prolonged periods makes it more likely to impart metallic flavor.
Olive oil is a great option for seasoning your cast iron skillet because it is affordable and easy to find. It also has a high smoke point, which means it can withstand high temperatures without burning.
All cooking oils and fats can be used for seasoning cast iron, but based on availability, affordability, effectiveness, and having a high smoke point, Lodge recommends vegetable oil, melted shortening, or canola oil, like our Seasoning Spray.
If your pan is too hot—and this is true specifically if you're frying with butter—the milk solids in your butter will burn, and fast. A little brown butter is a good thing, but too hot and the solids will start to blacken and then you'll be in trouble.
Cast iron pans are poor conductors of heat: Without getting too nerdy here...a cast iron is good at retaining (keeping) heat, but it isn't as good as conducting (transmitting) heat. A cast iron pan will heat unevenly if you're using a burner that's significantly smaller than the pan itself.
Why Use Cast Iron? Cast iron is ideal for frying and baking because it holds heat much longer than aluminum pans. The food in contact with the pan will sear nicely, while the food above it will cook through radiant heat. This is possible because of the high melting point of the cast iron material.
The least toxic cookware are non-stick pans and pots, like cast iron, stainless steel, ceramic, glass, and enamel-coated cast iron. These options don't have any Teflon coating on them, making them safe to use.
The acidity of tomatoes makes them challenging to cook in cast iron. Anyone who's ever eaten a tomato or cooked with tomatoes can verify that this fruit is quite acidic. As it happens, the tomato's acidity is precisely why doesn't work well with cast-iron cookware, especially for long cooking stretches.
Professional chefs use cast iron due to its many advantages. Besides being durable and inexpensive, cast iron pans and pots are easy to clean and great at heat retention. These features allow chefs to whip up several meals, especially those that need low simmering and browning to prepare.
With a few simple tricks to choose the right oil and get your pan to that just-right temperature, you'll get eggs with crispy edges and runny yolks every time (if that's your jam). But don't worry, cast iron makes the perfect egg no matter how you like them done!
The Myth: You can't cook wine, tomatoes, or other acidic ingredients in a cast-iron pan. THE TESTING: When acidic ingredients are cooked in cast iron for an extended amount of time, trace amounts of molecules from the metal can loosen and leach into the food.
According to the United States Department of Agriculture, rust is not food safe and shouldn't be ingested. That being said, it's unlikely that a rusty cast-iron skillet will harm you.