Aluminium foil, also aluminum foil (USA), al-foil, tin foil, is a thin sheet of aluminium that can be used as a wrapping or pliable cover in baking, barbecuing, roasting and as insulation. It is available in rolls of varying widths, lengths, and thicknesses.
When barbecuing foods that would dry out or scorch in direct contact with flame, wrapping in foil helps to retain moisture and flavour. Whole fish may be wrapped in foil with a thin coating of oil on the fish, and a sprinkling of dried herbs and spices, before placing on the barbecue. Whole potatoes can be individually wrapped in foil before tossing into the hot coals, for later retrieval.
In baking and roasting, foil can be used to wrap or cover food to protect it from direct heat in the oven. It can also be punctured, allowing excess moisture to escape if required.
Aluminium foil is not suitable for use in microwave ovens.