

The russet, a potato variety that's widely touted as the best for chips, has a high relative starch content and high density, which keeps the oil from penetrating too deeply. They don’t need to be, because potatoes naturally have plenty of starches.


What’s more, starch has the potential to undergo the chemical reactions that cause browning and caramelising – key to the sweet notes in a good fried food.Ĭhips aren’t cooked in batter, of course. A starchy batter can, though, and the more the starch molecules latch onto each other, in a process called cross-linking, the more water is expelled and the crunchier the outcome. Most things can't form a solid shell fast enough. At the same time, oil will seep in, making the food leaden and soggy. The shell must form instantaneously, or the vapour will continue to seep out, dampening the outer layer and desiccating the interior. This steaming process is why so many deep-fried foods are battered – onion rings, fish, corn dogs, Oreos, and Mars bars, to name just a very few.
