Why Doesn't Aluminum Foil Get (Feel) HOT When Removed from the Oven?

The thermal mass of an object is its ability to store or absorb heat. Things that are considered ‘difficult’ to heat generally have a high thermal mass. Brick or concrete, for example, heat up only after they’re provided with a lot of heat energy. In contrast, lightweight objects, like wood, have low thermal mass because they’re not good at absorbing or storing heat. Aluminum foil has a low thermal mass on account of having low mass and a high surface area. That’s why aluminum foil is not able to ‘hold’ much heat. These factors combine to make aluminum an ideal choice for wrapping things, because it doesn’t hold a lot of heat. And whatever small amount of heat it does hold, it gets transferred out of it quickly due to the high thermal conductivity of metal.