The secret to better frying

Creating the perfectly crisp french fry or golden brown piece of crunchy fried chicken can be frustrating. How to ensure that the food is properly cooked inside while maintaining a good crust is a challenge. Many factors go into creating perfect fried foods, but one technique can make the difference between good and great, says NPR’s The Salt.

Double-frying can be the key to getting the crispest, crunchiest fries, chicken, and more. Getting rid of excess moisture is one step in the process. That’s what makes the sizzle when you drop food into hot oil. “A lot of people say the oil is boiling,” says Scott Paulson, a physicist at James Madison University. But what’s actually happening, he says, is “you’re boiling the water very near the surface of the food.”

As the food cooks, a crust is formed. However, water that is lurking under that crust can’t easily escape, which limits how thick and crunchy your crust can get. That’s where a second, separate frying session can be helpful. Kenji Lopez-Alt, author of The Food Lab, explains it this way: “moisture in the center of the food migrates to the surface after the food cools and the surface gets soggy again. Then you boil off that moisture again on the second fry.”

There are two explanations behind the success of the double-frying technique. One is that foods get crisper because there’s less water in the food after the first fry. The second “is that the first fry changes the microscopic architecture of your food. During frying, oil pushes into the food through air pockets that are, in the beginning, warped and twisted channels.” As the cooking continues, the pathways start to merge with each other. During the second fry, “these straightened, simple pathways make it easier for water to escape, giving you a drier, crisper fry.”

Photo of Perfect thin and crispy French fries from indexed blog Serious Eats