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.
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). To keep the potatoes from turning black from oxidation, add 1 teaspoon of lemon juice or white wine vinegar to a gallon of water.
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.
(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.)
Remove the potatoes from the soaking water, place them in a towel and squeeze out as much moisture as possible. Allow the water to rest for about 30 minutes so the starch settles. Pour the water out of the bowl, leaving the starch at the bottom of the bowl. Combine the starch and potatoes just before cooking.
If you're prepping with smaller pieces, don't soak for more than 12 hours. This trick is handy, but it'll only work for about 24 hours — so don't prep too far in advance. After too long they'll start to take on water and may lose their structure when you go to cook them.
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.
Once it's time to cook with the potatoes, drain and rinse again with cold water. Washing the potatoes twice with water will remove excess starch, which will help them to get extra crispy when roasted or fried.
soak your potatoes in room temperature water for 2 hours before you bake them. Yep! It really does make a difference. While resting in the water bath, the potatoes will soak up some of the water and this, in turn, will help make them fluffy inside when you bake them.
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.
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.
Potatoes will be firmer and crispier if you soak them in salt water before frying or cooking. Although it may seem like an extra step, this process will help you prepare the potatoes in advance.
As soon as you peel the potatoes, you'll want to place them into a bowl of water so they're fully submerged, and then store the bowl of potatoes and water in the refrigerator. The water will seal off the potatoes from the air, so the chemical reaction can't occur.
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.
If it will be longer than a few hours, place them in the refrigerator. Peeled, sliced, submerged, and refrigerated potatoes should be cooked within 24 hours.
If you want to get ahead, why not boil them in advance, then toss in a little oil and store in the fridge until you're ready to roast them. There's no need to bring them back up to room temperature, just toss them into hot fat straight from the fridge.
Prior to cooking potatoes, one way to reduce acrylamide formation is soaking them in water. According to the FDA, soaking potatoes in water for 15 to 30 minutes is sufficient to reduce the levels of acrylamide during cooking.
The boiling point
The most important part here is that you use cold water instead of boiled – if you boil the water first, the outside will cook faster than the inside resulting in an uneven texture. Cubed spuds will take around 15 minutes where larger chunks or whole new potatoes will be 20-25 minutes.
Soak the potatoes in water for at least 4 hours, up to overnight. This step is crucial to really get all of the excess starch off. Fill a large pot with water, rinse off the potatoes one last time and add them to the cold water. Salt the water, place the pot on the stove and turn on the heat.
Doing so is a science thing – soaking cut potatoes removes excess potato starch. This means fluffy mashed potatoes (and not gluey!)
Cold cooked potatoes are great for your gut health because they contain resistant starch which help feed the beneficial bacteria. Once cooled the sugars in the potatoes become resistant to human digestion, but they travel through the gut to feed the microbes.
According to Boyers, the starch in potatoes is resistant to digestion, which means it travels to your large intestine and acts as a probiotic, AKA food source for your essential gut bacteria. It also helps create fatty acids that protect the gut lining and prevent harmful substances from leaking into the bloodstream.
Don't fry 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.
Do you need to soak potatoes before making mashed potatoes? No. You don't need to soak potatoes before making them into mashed potatoes.