If there are rust spots on the inside of a cast iron skillet, it is generally not safe to cook with it until you address the rust issue. Cooking with a rusty cast iron skillet can lead to health risks and compromise the quality of your food. Here's what you can do to restore your cast iron skillet and make it safe to cook with again:
Inspect the rust spots: Check the skillet thoroughly to see the extent of the rust. If it's just a small area, you might be able to address it easily.
Scrub the rust off: Use a stiff brush or steel wool to scrub off the rust spots. You may also use a mixture of equal parts water and white vinegar to help remove the rust. Make sure to scrub until the rust is completely gone.
Wash and dry the skillet: Once you've removed the rust, wash the skillet with warm, soapy water to remove any residue. Rinse it thoroughly and dry it completely to prevent further rusting.
Re-season the skillet: Seasoning is a crucial step in maintaining cast iron cookware. Coat the skillet with a thin layer of vegetable oil or melted shortening, both inside and outside. Wipe off any excess oil with a paper towel. Place the skillet upside down in an oven preheated to 350°F (175°C) and bake it for about an hour. Let it cool in the oven.
Store the skillet properly: To prevent future rusting, store the cast iron skillet in a dry place. Avoid leaving it in a damp or humid environment, as moisture can promote rust formation.
Remember that cast iron cookware can last for generations if properly cared for. Regular seasoning and maintenance will keep your skillet in excellent condition and safe to cook with. If the rust issue is extensive or difficult to remove, it's best to consult with an expert or consider replacing the skillet.