See full disclosure. Since aluminum foil has a shiny side and a dull side, many cooking resources say that when cooking foods wrapped or covered with aluminum foil, the shiny side should be down, facing the food, and the dull side up.
Subsequently, is there a difference between the two sides of aluminum foil?
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According to Reynold’s Kitchen, the difference in appearance between the two sides of aluminum foil is simply a result of manufacturing and serves no real purpose. Meaning, whether you are cooking your food with the shiny side up or the dull side up, you’re doing it right.
Herein, why does aluminum foil have a shiny side and a dull side?
Two layers of foil are pressed together and milled at the same time, because otherwise, it would break. “Where the foil is in contact with another layer, that’s the ‘dull’ side,” Reynold’s explains. “The ‘shiny’ side is the side milled without being in contact with another sheet of metal.