You're boiling milk, you turn your back for a moment, and — boom! — like Godzilla rising out of the bay, the milk is boiling over the pot and all over the stove. Prevent that mess with this simple hack.
First, courtesy of food blog thekitchn, a little background on why milk boils over, unlike a pot of plain water:
As milk heats, the water in its structure starts evaporating from the surface. This concentrates the remaining fat and proteins into a thicker layer at the top of the pot. This layer eventually becomes so thick that water vapour rising through the milk can't break through very easily and gets trapped.
While this complex interaction of protein and fat is what makes milk awesome for things like the creamy froth that goes into cappuccinos, it's also the reason that it boils over. The quick and dirty fix for the problem is to put a long-handled spoon into the pot as it is heating. The spoon breaks the surface tension and the skim of milk fat and protein forming and allows the steam to escape without violently erupting. It's a trick your grandmother might have known, but not something she necessarily felt the need to pass on in the age of microwaves.
Not as popular as they were in generations past, you can also use a milk watcher. A milk watcher is essentially just a glass, metal or ceramic disc that helps to distribute the heat and steam in such a way to prevent film from forming on the surface. You can pick a glass one up for a few bucks at specialty food stores or online.
Have your own cooking tip or trick to share? Pleased to finally know why exactly your grandma used to throw a little metal UFO into the hot chocolate pot? Let's hear about it in the comments.
Why Milk Boils Over...And How to Stop It! [TheKitchn]