Editing Microwave oven (section)

=== Penetration ===
Another misconception is that microwave ovens cook food "from the inside out", meaning from the center of the entire mass of food outwards.{{Citation needed|date=February 2025}} This idea arises from heating behavior seen if an absorbent layer of water lies beneath a less absorbent drier layer at the surface of a food; in this case, the deposition of heat energy inside a food can exceed that on its surface.{{Citation needed|date=February 2025}} This can also occur if the inner layer has a lower heat capacity than the outer layer causing it to reach a higher temperature, or even if the inner layer is more thermally conductive than the outer layer making it feel hotter despite having a lower temperature. In most cases, however, with uniformly structured or reasonably homogeneous food item, microwaves are absorbed in the outer layers of the item at a similar level to that of the inner layers.{{Citation needed|date=February 2025}}

Depending on water content, the depth of initial heat deposition may be several centimetres or more with microwave ovens, in contrast with [[grilling|broiling / grilling]] (infrared) or convection heating methods which thinly deposit heat at the food surface. Penetration depth of microwaves depends on [[food composition]] and the frequency, with lower microwave frequencies (longer wavelengths) penetrating deeper.<ref name="depth"/>