Leaving a cast iron pan on a hot burner for an extended period, such as one hour, can have several consequences:
Warped Pan: The intense and prolonged heat can cause the cast iron pan to warp or deform. Cast iron is a sturdy material, but extreme temperature changes can lead to structural changes in the metal.
Seasoning Damage: If the pan is seasoned (coated with a layer of oil to prevent rust and enhance non-stick properties), the high heat for an extended period can damage the seasoning. It might lead to the seasoning flaking off or becoming uneven, reducing the pan's non-stick properties.
Discoloration: The surface of the cast iron pan may become discolored due to the heat exposure. It might turn dark or develop spots.
Smoke and Fumes: The oil or any food remnants in the pan might start to smoke and produce strong, unpleasant fumes, especially if it reaches its smoke point.
Rust Formation: If the pan was not properly seasoned or the seasoning gets damaged during the process, leaving it on the burner for an extended period can lead to rust formation.
Fire Hazard: Leaving a pan unattended on a hot burner for too long increases the risk of a fire hazard, especially if there are flammable materials nearby.
It's essential to be attentive while cooking and avoid leaving the stove unattended for extended periods. If you accidentally leave a cast iron pan on the burner for too long, turn off the heat immediately, let it cool down on its own, and assess any damage. You may need to re-season the pan and inspect it for any signs of warping or permanent damage. If the pan appears to be significantly damaged, it may be time to replace it.