To avoid the aluminum transfer (and unpleasant metal taste) that often occurs when lasagna or a casserole is covered with foil while it bakes, try this restaurant trick:I often have the problem of having the foil kind of dissolve when it comes into contact with acidic foods, such as the sauce in a lasagne. My solution also has been to put a plastic wrap covering under the foil. However, I always go back and remove it for fear of it melting in the oven. Has anyone else used or heard of having plastic wrap used in the oven like this?
Simply cover the dish tightly with clear film, or plastic wrap, before covering with foil. The film will not melt under the foil, yet will protect the flavor of your dish by avoiding prolonged contact with the foil. This works for oven temps up to 450 F.
I do this with everything I cover, even in the fridge. No metal taste for me.