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.
(If you decide to try soaking the raw potatoes anyway, they can be soaked in water in the refrigerator for several hours without any safety concerns. Potatoes can be soaked even overnight as long as they are in the refrigerator.)
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).
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.
You can prepare the spuds up to 24 hours before you need to cook with them. Then, on the evening you're planning to serve them, you can make creamy potatoes at the drop of the hat. Start by scrubbing potatoes under cool running water to remove dirt; dice, slice, or chop as directed in recipe.
Just be sure to store peeled potatoes in water for no more than 24 hours. After that, the cool refrigerator air will convert the starches in the potatoes to sugar, causing the flavor and texture of the spuds to change. Instead, just start cooking potatoes for a mash, potato salad, or hash browns.
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.
Give them a cold water bath: Once your potatoes are chopped, toss them into a large bowl. Then cover the potatoes completely with cold water and let them soak for at least 30 minutes (or up to overnight). This will help to rinse off the excess starch and help the potatoes crisp up beautifully in the oven.
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.
A: Yes, you will lose nutrients if you soak potatoes in water; the longer they soak, the more you lose. Potatoes are a good source of potassium, vitamin C and some B vitamins, and a portion of these water-soluble nutrients will leach into the water.
The additional step of allowing the peeled, washed and cut potatoes to soak in cold water removes excess potato starch from the outside. This will help with the crisping up of the potatoes when they bake or roast. Soaking the potatoes in cold water also prevents the potatoes from browning too fast when cooking.
After they've soaked awhile, drain the fries, then lay them on a bunch of paper towels to dry them off. Blot the top of the potatoes to remove all the excess moisture.
Hard Vegetables (Potatoes, Carrots, Beets, etc.): Marinate these veggies for at least 30 minutes and up to overnight. Semi-Hard Vegetables (Green Beans, Asparagus, Peppers, etc.): Marinate for at least 30 minutes and up to several hours.
The best way to remove starch is to soak potatoes in water. It's difficult to remove too much starch—a potato is about 80% water and 20% starch.
Leaching method: Peel and dice potatoes. Place in a large pot of warm tap water and soak for 2 to 4 hours. Drain and set aside.
Soak raw potatoes in a container for up to four hours. The potatoes should be fully submerged to prevent oxidation and discoloration. After four hours, the potatoes should be rinsed with cold water. Chopping, cutting or otherwise slicing the potatoes will excrete more starch.
Starch Content by Variety
The starches are actually desirable when making mashed potatoes or baked potatoes, because they have less moisture inside and can absorb liquid well. This quality also leads to soft, mushy centers and potatoes that stick together, so starch removal is necessary to make crispy fries and chips.
The excess potato starch that forms when potatoes are peeled and sliced must be rinsed off the chips with water. If not, the surface starch will block the evaporation of moisture from the potato and lead to mushy, dark brown chips.
You can store peeled potatoes in water in the refrigerator for about 24 hours. Peeled potatoes left out by themselves at room temperature, on a refrigerator shelf or wrapped in foil or plastic wrap will still get dark overnight, so submerge them in a bowl of water, cover and refrigerate.
For the most effective potassium removal, potatoes must be cut into small pieces, sliced thin or grated. If boiled at least 10 minutes in a large pot of water, potassium is reduced by at least half the original amount.
In fact, potatoes rank highest for potassium content among the top 20 most frequently consumed raw vegetables and the top 20 most frequently consumed raw fruits. One medium potato (5.3 ounces) with the skin contains 620 mg of potassium. That's 15% of your daily requirement and more than a banana.
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.
Vinegar causes the potatoes to form a thin crust that further helps in retaining their shape. Vinegar increases the acid pH levels of water which further helps the potato just like when you add a little salt to the water while boiling eggs.
If you're here, you'll probably be glad to know that yes, you can peel and cut potatoes the day before you plan to serve them — and that it's super easy! All you have to do is submerge the bare potato pieces in water and refrigerate (more on that later).