How does the frosting on Pop-Tarts not melt off in the toaster?

The frosting on Pop-Tarts does not melt off in the toaster because it is specially formulated to withstand the heat generated during the toasting process. Pop-Tarts are designed to be toasted, and the frosting is made to melt just slightly and then set quickly, creating a gooey and sweet glaze on the surface without completely liquefying.

The frosting on Pop-Tarts typically contains ingredients like sugar, corn syrup, and starch, which can help it maintain its texture when exposed to heat. These ingredients give the frosting a more solid and stable structure, allowing it to soften and caramelize during toasting while still holding its shape.

Furthermore, Pop-Tarts are designed to be toasted for a short period of time, typically a minute or less, which is not long enough to completely melt the frosting. This controlled toasting process ensures that the pastry becomes warm and slightly crispy while the frosting remains intact, resulting in the familiar sweet and slightly crunchy topping that many people enjoy.