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By Judy = Oklahoma 09/27/2011
The food is turning black because either it isn't seasoned well enough, you're using very acidic food, or you're letting the food sit in it too long. As far as I know, it's not going to really hurt anyone to eat the food if it's not a real dark color, but it might have a metallic taste that's not too great. However I wouldn't recommend letting small children or pregnant women eat much of the food that is black/greenish, because of the high iron content.
I used to cook my spaghetti sauce in my cast iron dutch oven, because acidic foods draw even more iron out & I had a problem with anemia. I discovered that if I didn't season the pot after cooking acidic food, then the next time I used it to roast a chicken & veggies in the oven, they all came out with that greenish/black tinge. I was horrified the 1st time it happened & threw everything out. Then I learned it was safe & didn't taste bad if it was only slightly discolored - if you can get past the color, LOL! When I finally remembered to re-season after my spaghetti sauce, the problem was solved.
Here's a great site with all kinds of recipes & information on how to use your cast iron cookware:
By Tyara Mercado 09/18/2011
Thank you, Mrs Story, I will do that and post a feed back. I threw out the stew. Afraid to poison everybody! I am a little scared to try again. I must admit.
By Lisa 09/18/2011
I've never heard of cast iron going bad. I would scrub the inside like crazy (I'd start with a green Scotch Brite, and move on to steel wool if necessary), then season it. That's what I had to do with a wonderful old rusty pan I picked up at an antique shop. I scoured away all the rust and seasoned it and it was fine. Do you know how to season cast iron? My mom puts oil/grease on hers and sets it on a high burner (gas) for a while. I have a pan my dad bought for me when I moved out, and it has instructions on the bottom. It says to scour the pan, coat in cooking oil, leave in a 300-degree oven for one hour, then wipe off excess oil. It took time for mine to get a good finish on it, but this should help. After it is well-seasoned, you shouldn't have to soak it in soapy water and scrub too much. If I cook something that sticks (like something that caramelizes), I put hot water in it and let it sit while I'm washing the rest of the dishes. Then I just use the green Scotch Brite to clean it. Afterwards I wipe on a little more oil, and that's it. I don't heat it in the oven again. With experience, you'll be able to tell how it looks after you've cleaned it if you need to season in the oven again.
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