what is a beer keg made out of
Keg More recently, a keg is often constructed of aluminum or steel. It is commonly used to store, transport, and serve beer. Other alcoholic or non-alcoholic drinks, carbonated or non-carbonated, may be housed in a keg as well. Such liquids are generally kept under pressure.
Anheuser-Busch brands AmberBock is a 5.1% ABV amber lager which uses roasted black barley malt in the ingredients, and which received a World Beer Cup Bronze Medal in 1998.