A lot of times when I use my cast iron pan, I'll sometimes get some "black stuff" which I assume is gristle on my food. It doesn't taste bad, it's not a "TON" - I'm assuming it's a combo of burnt+black stuff from the cast iron pan.
Is this in any way dangerous?
Black stuff on a cast iron skillet is most likely just a thin layer of burned food. It's not horribly dangerous (I'm sure you've eaten some charred things before) but it does make your food look worse, so you may as well just keep your skillet clean and well-seasoned and avoid it.
The "black stuff" is either bits of charred food from your last meal or flakes of the polymerized oil that is the "seasoning" coating. Neither will hurt you. I have cooked with cast iron for more than 30 years. It is tough and very near care free. I might season a pan a couple time in the first month after buying but after that there is just no need.
Black iron pans have been in use for hundreds of years. They can be used over an open fire, scrubbed out with a hand full of sand from the brook and dried with your shirt tail. If you use that method however you will need more frequent seasoning because sand is very hard and sharp. I clean mine with a plastic scrubby under running hot water and virtually never need to season it.
(I'll bet the frequent seasoning thing got its start back when sand was being used as a cleaner.)
If you need to re-season your cast iron, first rinse carefully and put it upside down in your oven on self-clean. It will remove all the "dead black crust" and leave it brand spanking clean. THEN, rub it down all over (especially inside) with a layer of shortening and put it in a slow over (250 def.) for a couple of hours. Turn off the heat and let the pan cool inside the oven.
That black stuff is a phony pre-coated seasoning on these newer Skillets that shouldn't be there. To start with I took a grinder and got rid of that stuff on my pan.A real cast iron skillet is smooth not bumpy and it's not painted with anything. To pre-seasoned you have to wash it ,dry it or let It season it by putting it in an oven at 250 degrees that actually burns a layer of oil onto the surface and makes it non-stick. These new Skillets coming out with this black stuff on it, that's what's coming off on your food and it shouldn't be there.. also once it's seasoned never ever wash it with soap again .The soap will cut the seasoning, simply wipe it out to clean it and put another layer of oil on it. To start from scratch and clean the entire pan after it's been used for years and is crusty on the outside you throw it in a burn pile or burn barrel and burn it with the trash. when the ashes are cool take it out it'll be spanking new clean and you can start reseasoning it again. Im from old North Carolina hill people. I know who to wield a skillet!
