Cast iron cookware is durable, economical and a favorite of many cooks. A carbon layer will eventually build up in the interior of the pan, which prevents food from sticking. Cast iron retains an even heat, without hot spots that burn food. The cookware comes in several sizes of skillets and Dutch ovens. Yes, it is possible to put a cast iron pot in the fridge, but it's not recommended.
You should not put a hot pan in the fridge for several reasons. The hot pan can crack the glass shelves. Or the cast iron pan might react to the cold temperatures and crack itself. Finally hot food raises the internal temperature of the fridge. One of the advantages of a cast iron pan is that it retains heat. That heat can raise the temperature above 40 F, the recommended safety level by the U.S. Department of Agriculture.
Another reason not to put cast iron in the fridge is because acids in the food eat away at the carbonized seasoning on the pan's cooking surface. This causes pitting, which means food will stick to the pan. Also, moisture in the foods causes the surface to rust. The rust has to be removed, and when you do that, you also remove the pan's seasoning.
Storing food in a cast iron pan might lead to iron toxicity, according to Drweil.com. This is caused by ingesting too much iron. The iron is caused by the moisture that sticks to the food. When the food is ingested, so is the iron. In small quantities that's not a problem. However, for those people who have difficulty metabolizing iron, or hemochromatosis, that excess iron leads to fatigue, joint and stomach pain as well as other symptoms.
If you have left food in your pan, you will need to re-season it. The process to re-season a cast iron pan is the same as the original seasoning process -- with one exception. Scrub out the pan to remove all traces of food and rust. The cooking surface has to be smooth. Wipe down the pan, inside and out with animal fat such as pork or lard. The jury is out on whether vegetable oil can be used. Some cast iron aficionados say absolutely not, it must be animal fat. Others say fat is fat. Put the pan in a pre-heated 350 F oven for one hour. Place a cookie sheet covered with a paper towel so any excess fat doesn't drip on the oven floor. Bake for one hour. Cool and wipe dry.