Here's what I got last year from the list. Your guess is as good as mine.
-----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Seigenthaler Family Sent: Friday, February 25, 2011 2:46 PM To: [email protected] Subject: [CnD] Scientific answer about foil When I googled this, I got two very different answers. I'm going with the first. 1. Take it from the people at Reynolds. They make the stuff. They will tell you that it makes no difference which side is in or out. Optical light scatters differently from the dull side than from the shiny side, which is more like a mirror. But both sides absorb or reflect light (and infrared radiation) equally. 2. Answer below from: http://www.newton.dep.anl.gov/ The shiny side of foil is slightly better reflector of heat. Face that side of the foil in the appropriate direction. To keep things cold, put the shiny side on the outside -- that will reflect incoming heat. To keep things warm, face the shiny side inward toward the hot food -- to reflect the heat that is trying to escape back into the food. Note that people often bake potatoes with the shiny side out -- that is because it makes for a better (prettier) presentation. In reality, baking them that way reflects the incoming heat on the outside, slightly slowing the cooking process. Radiative heating will happen by the absorption of infrared radiation (IR radiation) or heat emanating from all around the food (within the BBQ). Now please consider infrared radiation to be in the wavelength range of 880 nanometers or so. Realize that this wavelength of "light" is very near the color red in the visible portion of the spectrum. Further, this means that the radiation will act like light and the foil shall act as a mirror. Knowing now that you want to transmit (foil to absorb all radiation) as much IR through the foil as possible. It should be clear to you that the dull side should be OUTWARD facing so as not to minimize the reflection of IR radiation. Carrie _______________________________________________ Cookinginthedark mailing list [email protected] http://acbradio.org/mailman/listinfo/cookinginthedark _______________________________________________ Cookinginthedark mailing list [email protected] http://acbradio.org/mailman/listinfo/cookinginthedark
