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    $\begingroup$ "and it mostly flows to the environment, not to your hand." I'm not sure if that part would be true. Hands are pretty good at taking heat; we even have a forced fluid circulating under our skin that can quickly carry heat away. Although your hands are only a small area; they also provide a really effective cooling route for the foil. $\endgroup$
    – JMac
    Commented Feb 12, 2018 at 16:08
  • $\begingroup$ @JMac: Thanks for the comment. I've added a comparison of areas. There are at least two orders of magnitude between the foil area and the contact area. $\endgroup$
    – Eric Duminil
    Commented Feb 12, 2018 at 16:20
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    $\begingroup$ @EricDuminil presumably the inside of the oven is much closer to the temperature of the foil. In fact, that's how the foil got hot in the first place. It cools down a bit when opened but it's still pretty hot relative to your body. $\endgroup$
    – JimmyJames
    Commented Feb 12, 2018 at 16:57
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    $\begingroup$ It should probably be noted that the heat loss by radiation for aluminium is rather low because it has a very low emission coefficient. It's in the order of 4 %. So radiation is a rather small contributor even if the area is rather large. $\endgroup$
    – Arsenal
    Commented Feb 13, 2018 at 16:28
  • $\begingroup$ @Arsenal That might actually play a substantial role in this scenario. A non-convection oven primarily transfers heat through radiation. That means that the foil is at a disadvantage there, and would be getting a lot of heat through secondary sources (conduction and convection). There's definitely a chance that the foil is significantly cooler than the oven temperatures; even though other exposed surfaces are near the oven temperature. That would just compound onto the cool feel. $\endgroup$
    – JMac
    Commented Feb 13, 2018 at 17:46