Salting before frying will prematurely breakdown the oil. Oil is the most expensive part of the formula for costing out making fries from scratch. Anything that shortens the time the oil can be used and can't be filtered out is not a good thing.
Potatoes soak up a lot of flavor, so salting the water prior to cooking is a good idea for the best taste. And you aren't limited to plain salted water for boiling your potatoes, either.
Whether or not you season the french fries before or after they are cooked depends on the cooking method that you use: Deep Fried french fries are seasoned immediately after they're finished frying. Baked or Air Fried fries are seasoned before they're cooked.
Why use salt water for soaking potatoes? There's moisture naturally found in potatoes, and moisture is drawn to higher concentrations of salt. (This is a process called osmosis.) So, if you put the potatoes in a salt water bath, that will help draw out some of their moisture, resulting in crispier fries.
“Salting the water not only seasons the potato, but it also allows it to boil to a hotter temperature. This in turn cooks the potatoes' starch more thoroughly, resulting in a more creamy texture [for mashed potatoes],” says Sieger Bayer, Chef and Partner at The Heritage.
Leave the larger potatoes in the boiling salt water and remove as they become tender. Overcooking the potatoes may cause them to split, which infiltrates the salt inside the flesh.
This in no way means that your water will boil faster, however, which is a common misconception among cooks. On the contrary, this simply means that salted water will become hotter, and your potatoes or pasta will ultimately cook faster will make your food taste better.
Add a raw, peeled potato into a pot of oversalted soup and let it simmer for around 30 minutes. Don't let the potato cook so long that it disintegrates into the soup. Allow it just enough time to almost cook through. The potato will soak up some of the salt and some of the liquid.
Soaking potatoes in water helps remove excess starch. Excess starch can inhibit the potatoes from cooking evenly as well as creating a gummy or sticky texture on the outside of your potatoes. Cold water is used because hot water would react with the starch activating it, making it harder to separate from the potatoes.
How long can peeled and cut potatoes sit in water before cooking, before they begin taking on too much water? A: We usually recommend no more than 24 hours. You can keep the potatoes from absorbing the water by making sure the water is not salted, and is chilled (you can even add ice to the water).
When it comes to the actual cooking, you want to fry the french fries twice. The first round is at a lower temperature to cook the inside of the potato and the second time you'll use a higher temperature to make the fries golden brown and crispy. You can use a home deep-fryer or just heat the oil in a Dutch oven.
The soaking, Mr. Nasr said, is the secret to the crisp texture of the fries. It draws out the starch, making them more rigid and less likely to stick together. The cooks fry them twice, first blanching them until slightly limp in peanut oil heated to 325 degrees, and again in 375-degree oil to crisp and brown them.
Season the fries: Be sure to season your fries while the oil is hot. The hot oil will help your seasonings stick to the fries. Use salt, spices, fresh herbs, or even oils to flavor your fries.
BOTTOM LINE: ADD SALT EARLY (OR SALT LESS LATER)
For the most even seasoning and well-rounded flavor, we strongly encourage seasoning foods early in the cooking process.
Place them in a large bowl and cover with cold water. Allow them to soak, 2 to 3 hours. (You can also stick them in the fridge and let them soak overnight.) When you're ready to make the fries, drain off the water and lay the potatoes on 2 baking sheets lined with paper towels.
Throw them in a pot or large bowl and cover them with cold water, then let them soak for at least two or three hours. Soaking the sliced potatoes is the fundamental first step of making proper french fries.
2. Frying fresh-cut potatoes. Soaking peeled, washed, and cut fries in cold water overnight removes excess potato starch, which prevents fries from sticking together and helps achieve maximum crispness.
Once the potatoes have soaked, rinse and drain them. Then — also very important — use a towel to pat them down until they are nice and dry before moving onto the next step.
Don't soak cut potatoes longer than overnight.
If keeping potatoes in water for more than an hour, refrigerate. However, don't soak them any longer than overnight—after that, the potatoes start to lose their structure and flavor.
Add enough cold water to cover the tops of the potatoes. Add ½ to 1 teaspoon salt to the water. Turn the burner on high and bring water to boiling. Reduce the heat to medium-low or low.
Make sure the potatoes are golden-brown on the bottom before you attempt to flip or move them. Think of it like searing meat — the potatoes will be easy to move around once they're browned and ready.
Use a Bigger Pan (or roast on a wire rack)
The more space your potatoes have, the more air can circulate around them, and the more heat gets into each piece of potato. The result? Faster cooking.
When broiling or searing, sprinkle salt after cooking, since the salt would slow the browning by drawing the juices to the surface. Salting before cooking may be done in a fast cooking process, which does not allow for toughening or moisture loss.
Water follows salt. By creating a salty environment around the fries, this will help draw out excess water from the potatoes. This will ultimately leave us with a super crispy, rather than mushy, final product.