Now and then, we want to place a sheet of aluminum foil on a baking sheet, for one reason or another. Often, it is simply because we know that what we are cooking is going to have messy spillover, and we want to make clean-up easier.
You may have noticed that it can be a bit of a pain to get a sheet of foil to lie flat. You push one end down, the other end pops up. I know this isn’t exactly the most monumental problem, but it is annoying.
What to do? How can you get the foil to lay nice and flat on the pan?
The solution is simple and quick. All you have to do is dampen the pan a bit. Just rub a little water on the pan, either with your hand or a damp cloth. Make sure you coat the entire pan. Then just place the lay the aluminum foil on the wet pan and press it down. The water will act a bit like glue, and the foil will lay down perfectly, a resist moving around.
This same solution, by the way, works on the counter if you need to get parchment paper or wax paper, not to mention foil, to lay down flat. Wipe the area of the counter you need to use with a damp cloth, and the parchment paper, wax paper, or foil will lie flat on the counter, and will not tend to slide back and forth while you are using it.
I actually figured this out on my own one day. Sadly, though, I didn’t invent it. I’ve found the same tip in cooking magazines and books. Maybe I’ll think of something original, one day!
Water acts somewhat like a (weak) glue. It has fairly good adhesive properties. But, it also has fairly good cohesive properties. This means that it likes to stick to other things, and to itself. So, the water molecules are clinging together, but also clinging to the metal surfaces. There may be other forces at work here, as well, that contribute to the effect.
See also Aluminum Foil: Should the Shiny Side be Up or Down When Cooking?