Making sweet potato fries is easy: Toss them in oil, add some herbs and spices, then bake or air fry — or simply toss them into a deep fry. Right? Not so fast. This method will undoubtedly result in soggy limp fries.
The reason? You're missing one key step to making those delicious morsels closer to that satisfying crispy texture characterized by their white-potato cousins. Try soaking them in a bowl of cold water for at least 30 minutes to overnight, then pat them dry before seasoning and frying. Soaking helps draw out the starches that would otherwise break down and become gelatinized during cooking, leaving you with a sad saggy fry.
Surprisingly, the amount of starch found in raw russet potatoes (13 grams) and raw sweet potatoes (16 grams) differs only by about 3 grams. As such, the Idaho Potato Commission also recommends soaking those russets before cooking for the same reasons. Amylase: it's what makes those unsoaked fries limp What happens as sweet potatoes cook and how you prepare for it is what will determine whether you're crowned sweet potato fry royalty or not.
Sweet potatoes contain enzymes called amylase. As sweet potatoes cook — regardless if you're frying them in oil, cooking them in an air fryer, or baking them in the oven — amylase breaks down the starches into simple sugars which become gelatinized, causing the fries to absorb water. Hence, limp fries.
Removing some of the starch by soaking the potatoes limits the amylase reaction. In lieu of soaking, .
