Problem with baking sheets
Maybe I am cleaning them improperly or doing something wrong, but my baking sheets form a corrosive metallic film over them when I wash them. When I dry them with a towel, the towel is gray from the nasty residue. These are allegedly high quality aluminum baking pans. When I bake on them, I just try to wipe them well and then line the pans with foil or parchment. Just seems that the pans should not be covered in this stuff. I am thinking I just need to buy stainless steel pans to avoid this problem. Has anyone has this experience and have you used solid stainless steel pans? Any thoughts on this problem and if stainless steel is better?
Use less harsh detergents. It's aluminum oxide. Totally harmless, but you shouldn't be shedding it with that regularity, unless you're using nasty alkaline detergents on them.
Yes, but also no.
What you observed is most likely oxidized alumium, aluminum oxide. It really does not matter your sheets are high quality or not. Bare aluminum can oxidize to form a gray color layer. It is nothing to worry about. It is prized by many as it is the same as anodized aluminum.
Stainless steel baking sheet will not have this problem at all. However, stainless steel baking sheet is not a good heat conductor like aluminum.
Yes, these are Chicago Metallic pans. I'm glad to know the residue is harmless but it still makes me reluctant to place food on them directly (I used one last night to oven bake some salmon and I lined the pan). I don't use harsh detergents--usually just use natural soap products (e.g., Meyers, etc.). Maybe I'll keep these for baking and get a stainless pan or two for things like potato or fish baking when I am using olive oil and lemon. Thank you all for your responses.
A couple of things...
As others have said - oxides of aluminium. You will get the effect you mention if you use steel wool to clean them. The film is corrosion, not corrosive. In fact the oxides are very stable compounds. The problem comes when you get the gunky brown residue from fats - and the only way to remove them in an abrasive.