A friend baked a rum cake for me. She baked it in an aluminum pan. The cake was soaking in rum. Overnight the cake turned BLACK. I suspect this is a chemical reaction, but cannot find information to back my theory. Surely, this may not be safe to eat. Anybody?
Aluminum cookware is "reactive", as opposed to "non-reactive" cookware like glass or stainless steel. When cooking acidic ingredients, a reaction occurs that can discolor food and sometimes leave a taste of tin. It would appear that the rum cake in question was acidic enough to cause this reaction. While I have yet to come across anything that says this is dangerous, I have come across several discussions that say aluminum discolored food is "ruined."