I just thought I'd start this thread as cooking today's roast, I noticed something on the tin foil box. "always use the non-shiny side". Now why is this the first time I have heard of this? I always thought the shiny side would reflect more heat and be my hygienic as it's less likely to have any surface area and loose molecules than a matt surface. but no bacofoil say otherwise.

Can someone shed light on this?

It’s a well-established question and one that we’ve been too afraid to ask our mothers: Should we use the shiny or the dull side of aluminum foil when we cook? And have we been doing it wrong this entire time?!

Concerned cooks, you can breathe a sigh of relief: As it turns out, there’s no “correct” side of aluminum foil to use when cooking so using it on either side is not one of the cooking mistakes that could ruin your food. According to the Huffington Post, they’re both equally effective at heating your food—so just choose whatever side you prefer.

If there’s no trick to it, then why, exactly, does aluminum foil have a shiny and a dull side in the first place? Experts at Reynold’s Kitchen say that the difference between the two sides is due to a manufacturing process called milling, during which heat and tension is applied to stretch and shape the foil. 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. The performance of the foil is the same, whichever side you use.”

But pay attention if you are using non-stick foil; in that case, there is a difference between the two sides. Since the non-stick coating is only applied to one side, you’ll want to use the dull side. Side note: There will be a label that designates the “non-stick side” in case you forget.

There is a big debate as to whether you hold it sideways to the can or horizontally on top of the lid. I do the latter so that the whole lid comes off, but apparently you aren't supposed to do that (health and safety).....

I'm confused. You say you 'do the latter' (i.e. use the opener horizontally on top of the lid) which is apparently wrong - but in the video she shows that using it that way is the right way

Did you mean to say you 'do the former'? Or am I just not getting any of this at all (entirely possible based on my life experience )

I believe it is because the non shiny side won't stick to the food... at least that is what it says on my current roll, but that is how I have always used it anyway!

I do it the way it says is right in the video but on a recent twitter storm people were saying that's wrong. It's as contentious an issue as whether you put the loo roll with the paper under or over. Just happened to find a video clip that agrees with my method Ring pull cans are the best way to resolve the matter!