roll: aluminum foil

Aluminum foil is a thin sheet of aluminum metal, typically 0.016 mm thick, produced through the rolling and flattening of aluminum ingots. It is a non-food ingredient used primarily as a cooking and food storage material rather than a consumable ingredient. Aluminum foil is valued for its impermeability to light, moisture, and oxygen, as well as its heat conductivity and flexibility. The foil can be used on either side—the shiny side reflects heat more effectively, while the matte side absorbs slightly more heat, though the difference is negligible in most cooking applications.

Aluminum foil is used extensively in the kitchen for wrapping foods before cooking (en papillote), covering dishes during baking to prevent over-browning, lining baking sheets, and storing leftovers in the refrigerator and freezer. It is particularly useful for steaming foods, protecting edges of pies and breads from burning, and creating sealed packets for grilling or oven-roasting. The foil's malleability allows it to conform to various dish shapes, and its non-reactivity with most foods makes it suitable for prolonged contact.