Deep-Frying: A Savory Science

Unlike heating a meal on your car’s engine block, cooking food in a deep-fryer doesn’t first require a series of reckless burnouts. Read on to discover why there’s virtually nothing that can’t be improved with a little hot oil.

There’s a simple chemistry at the heart of deep-frying, the notoriously tasty cooking process by which edibles are submerged in hot oil. Because lipids repel water, the sizzling oil bars the moisture within food from escaping, essentially steaming it from within to create a crispy outside and a rich, sumptuous mouthfeel. Cheesecake, lasagna, and even butter have been subject to the experiments of domestic deep-fryers such as Paula Deen, but immersing food in boiling oil is a practice prevalent throughout the world, used to create Italian arancini balls, Japanese tempura, and Indian pakoras.

Although some chefs, such as Mario Batali, use olive oil for deep-frying, peanut oil, safflower oil, or ghee are more popular choices because they can reach higher temperatures without smoking. Regardless of the oil used, the optimal temperature window for frying is generally between 345 and 375 degrees Fahrenheit. Soggy and greasy food indicates the oil is too cool; food burnt on the outside with an undercooked interior suggests the oil is too hot.