There are many myths surrounding the difference between the shiny side and the dull side of aluminium foil.
So which side is the right side?
The truth is, there is no difference.
According to U.S. foil company Reynold's Kitchen, the two different sides are simply the rest of the manufacturing process.
So there is no right way up for cooking.
The company goes into more detail on Reynold's FAQ page:
"This is a common question and the answer is that the foil is 'milled' in layers during production. Milling is a process whereby heat and tension is applied to stretch the foil to the desired thickness. We mill two layers in contact with each other at the same time, because if we didn't, the foil would break during the milling process. Where the foil is in contact with another layer, that's the 'dull' 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."
So now you know!
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