How does foil protect a sandwich in the [toaster] oven?

How does foil protect a sandwich in the [toaster] oven? - Photo of a Sandwich Beside a Black Dslr Camera

If I wrap a sandwich in foil and toast it, the entire sandwich seems to warm more evenly, so I don't get burnt edges of bread.

Can someone explain what is going on here?

I assume it has something to do with the ambient temperature cooking the sandwich instead of direct heat.

bakingfoil-cooking


Best Answer

I don't think it's just one thing:

  1. The foil reflects radiant heat, meaning that the only remaining way to propogate heat is through conduction and convection.
  2. The foil is an impermeable barrier which helps to keep the moist air (created by boiling off the moisture in the surface of the bread) near the sandwich, which reduces the rate at which the bread dries out, and we need dry items for them to burn.

It's possible that retention of the moisture within the foil slows the heating of the enclosed system as there's less loss of thermal mass, but I doubt that's a significant factor in most situations.

You might be able to test which of the other two is the more significant factor by running a test with foil that's been perforated such that it's not a good barrier but would still be reflective, and see how that compares.



Pictures about "How does foil protect a sandwich in the [toaster] oven?"

How does foil protect a sandwich in the [toaster] oven? - Man in White Shirt Looking at White Flower
How does foil protect a sandwich in the [toaster] oven? - Burger With Cheese on White Ceramic Plate
How does foil protect a sandwich in the [toaster] oven? - Woman in Blue and White Plaid Dress Shirt Sitting on Bed Beside the Side Table with Food


Quick Answer about "How does foil protect a sandwich in the [toaster] oven?"

The foil is an impermeable barrier which helps to keep the moist air (created by boiling off the moisture in the surface of the bread) near the sandwich, which reduces the rate at which the bread dries out, and we need dry items for them to burn.

Is it safe to use aluminum foil in a toaster oven?

You can use aluminum foil as a crumb tray in the toaster oven, as long as you don't lay it at the bottom of the oven or too close to the heating element.

What does wrapping a sandwich in foil do?

We recommend wrapping your sandwich with the foil side out to avoid charring on the paper. Please keep in mind that these are made to help insulate hot food and baking with these under high heat is not advised.


Can you put aluminum foil in the toaster oven?



Sources: Stack Exchange - This article follows the attribution requirements of Stack Exchange and is licensed under CC BY-SA 3.0.

Images: Nataliya Vaitkevich, Ron Lach, Rachel Claire, Ron Lach

Related Questions