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.
Does the shiny side go up or down on aluminum foil?
So, now that you know the reason behind the different appearance of the two sides, you’re probably wondering if you should use aluminum foil with the shiny side up or down. Quite simply, it doesn’t matter. Since both sides are made of the exact same material, they will perform exactly the same way.
Why does tin foil have a shiny side?
“The ‘shiny’ side is the side milled without being in contact with another sheet of metal. The performance of the foil is the same, whichever side you use.”
