Tin Foil

[snowangel]

One side is shiny, one side not shiny.

Is there a rule of them, when using it for cooking or storing, as which side should be shiny side next to food, or not shiny side up next to food?

And, is there an easy to remember jingle (a la the jingle to remember which months have 30 days?) to help me remember which side up?

[vice]

I recall hearing long ago (can't remember where) that the shiny side reflects more heat than the dull side. Thus, shiny side faces food when you want to concentrate heat; shiny side away when you want to deflect it.

[BistroPaul]

There is no practical difference in the thermal reflective characteristics of either side of foil. On technical level there is a difference, especially if the heat energy is coming from a light source but for any cooking purposes it is so small as to be completely irrelevant. The only reason that there is a shiny and dull side is because of the way they are rolled in the factory.

Paul

[Chris Amirault]

I heard once that the sheets were rolled out in pairs, and that, when pulled apart, the dull sides were on the interior. True?

[BistroPaul]

I heard once that the sheets were rolled out in pairs, and that, when pulled apart, the dull sides were on the interior. True?

Exactly. The sheets have to be rolled in pairs because they are too thin and would tear in the machine.

Edited October 26, 2009 by BistroPaul (log)

[Dave the Cook]

More detail from Reynolds:

In the final rolling step, two layers of foil are passed through the rolling mill at the same time. The side coming in contact with the mill's highly polished steel rollers becomes shiny. The other side, not coming in contact with the heavy rollers, comes out with a dull or matte finish.

[Anna N]

All this applies to REGULAR foil - doesn't matter which side is up. BUT the newer, non-stick foil, is different. The less shiny side should be the one touching the food. Formerly sold with the brand name RELEASE it is now sold as SLIDE. From my current package "SIMPLY WRAP OR PLACE FOOD WITH NON-STICK (DULL SIDE) FACING FOOD.

[Peter the eater]

Actual tin foil disappeared from Canadian grocery stores half a century ago, according to Alcan Inc. Apparently it's much stiffer and more dull-looking than the same thickness of aluminum foil.

[baroness]

Why is aluminum foil so often called tin foil?

[Jaymes]

Because that sort of foil was originally made of tin. So everybody called it 'tin foil.' When tin was replaced by aluminum, many folks continued to refer to it by the earlier, and, let's face it, easier, name.

I often still refer to it as 'tin foil' even though I very well know it's not. My elderly parents call it 'tin foil' because that's what it was when it first hit their mama's kitchens as a fabulous new invention.