Why do jacket potatoes sometimes burst?

Jacket potatoes sometimes burst because of the build-up of steam inside the potato. When a potato is cooked, the water inside it turns to steam. This steam can build up pressure inside the potato, causing it to burst.

There are a few things that can contribute to a potato bursting. One is cooking the potato at too high a temperature. Another is piercing the potato with a fork or knife, which can create an opening for the steam to escape. Finally, cooking a potato that has a thick skin can also increase the likelihood of it bursting, as the skin can prevent the steam from escaping.

To avoid a potato from bursting, it is best to cook it at a moderate temperature, avoid piercing it, and choose potatoes with thin skins.