TIL if you put aluminum foil over pasta it creates a battery

I once electroplated some Spanish rice by making it in a cast iron pan and covering it tightly with aluminum foil.

Because I was in college I ate the parts that weren’t silver. It tasted normal.

Surely this only works if the pasta is already in a metallic container made from some other metal than aluminum.

Surely this doesn't work if pasta is in a plastic container.