This Is What Happens When Water Hits a Hot Pan at 3000 Frames Per Second

Back in the 18th century, a German doctor called Johann Gottlob Leidenfrost described how water behaves when it hits a mass considerably hotter than its boiling point. But first, watch the 3000-frames-per-second video and see if you can realize what's happening.


As you can see, the water doesn't boil right away. You may have seen the same effect in your own kitchen. If not, here's the experiment: Get a dry pan, make it extremely hot, and drop a bit of water on it. If the temperature is high enough, you will see that the water drops will dance around the surface for some time before they disappear. If it's just below 100 ºC, however, the water will just flatten and evaporate slowly. If it's above 100 ºC, the water will quickly evaporate on contact. But when it gets to 190 ºC or 374 °F, the droplets will not evaporate for quite a few seconds. In fact, Sir William Fairbairn—a famed Victorian steam boiler designer—found that, while a water droplet evaporated in a hiss at 334 °F, it survived for an amazing 152 seconds at 395 °F (202 °C).

Illustration for article titled This Is What Happens When Water Hits a Hot Pan at 3000 Frames Per Second

The reason is called the Leidenfrost Effect: When the water touches the pan, a small layer of vapor forms around it. This vapor layer isolates the droplet from the hot surface and protects it from evaporation. [Modernist Cuisine via PopSci]



I was reading about this the other day when I was learning how to properly preheat a stainless steel skillet. If you heat it to the point of Leidenfrost, nothing will stick to the steel surface, so you don't need any teflon or anything. They say heat your pan with medium high heat and drop water droplets periodically. And when they form a ball and dance around like marbles, it's time to add your oil.