You can, but I don't. If you do – just soak them for 5 minutes and rinse. Doing so is a science thing – soaking cut potatoes removes excess potato starch. This means fluffy mashed potatoes (and not gluey!)
Running the potatoes through a food processor is the best way to release all the starch the potato has to give. Using an electric mixer to whip the potatoes releases some starch, but not too much. Last, but equally important, is the soaking and rinsing process.
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.
Soak it in salted water after peeling and cutting it into equal lengths. After 30 minutes, drain and replace the water. Then, in freshwater, boil it for 15 minutes.
The larger the potato pieces, the longer they'll last in water. 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.
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).
Do you need to soak potatoes before making mashed potatoes? No. You don't need to soak potatoes before making them into mashed potatoes.
What you do to your potatoes after soaking them in water depends on what you're using them for. For roasting: Pat the potatoes completely dry before adding oil and putting them in the oven, says Welsh. For frying: Rinse after soaking to rid the potatoes of excess surface starch, then drain and dry well.
Why soak potatoes in water before frying? 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.
How long do you need to soak potatoes? Soaking potatoes for 15 to 30 minutes is sufficient, but you can soak them for up to an hour, if you have other things to do around your kitchen. I think soaking any longer than that would be unnecessary.
Generally, soaking potatoes in salt water is a matter of personal preference. However, this process helps draw out moisture and starch from the potatoes and make them crispier.
Waxy potatoes have less starch than Starchy potatoes and contain more moisture and sugar. They are often smaller with a waxy outer skin and a creamy, firm and moist flesh. When to use: Waxy potatoes hold their shape well after cooking so are great for boiling, roasting or slicing.
Choose higher starch potatoes like Russets or Yukon Golds for the fluffiest, smoothest and most flavor-packed mash.
Luckily, there's a way to mitigate the tackiness: Stir extra fat into the mash, which helps coats the starch and makes the gumminess less noticeable.
According to Serious Eats, when your mashed potatoes end up with a pasty or a gluey consistency, it's due to an excess of starch. As a result, limiting the amount of starch in your dish is the key to nailing perfect mashed potatoes. Luckily, there's an easy way to do this: Don't overwork your potatoes.
Potato starch does not generally have many health risks for a person. Resistant starches, such as potato starch, act similarly to fiber, meaning there are very few side effects after consumption. However, some individuals may find that eating large quantities of potato starch triggers gas and bloating.
The more starch you remove, the lighter and fluffier your mashed potatoes will be. To remove excess starch you will want to rinse the potatoes after peeling and chopping them, and then rinse them again after boiling the potatoes.
First let's talk about why cut potatoes need to be immersed in water to begin with. The reason is to prevent the potatoes exposure to air, which causes dehydration, oxidation, and discoloration. Immersing cut potatoes will also help rinse off excess starch.
Prepping the potatoes ahead of time
To save time on peeling and chopping on Thanksgiving Day (or any other day that includes mashed potatoes), you can peel the spuds and keep them submerged in a bowl of water in the fridge, whole or cut up, for hours — even overnight — before boiling.
Keep Your Potatoes Hot
If you want a truly creamy taste and texture, you can't let the potatoes cool before mashing—you want to start getting busy with them as soon as possible after they've been boiled and drained.
Tips for the Best Mashed Potatoes
Start cooking the potatoes in cold water: This ensures that the potatoes cook evenly. Otherwise, if you start with hot or boiling water, the outsides of the potatoes cook and soften while the middles are still hard and crunchy.
Always start potatoes in cold water.
Dropping them into boiling water is a bad idea because the hot water will cook the outsides of the potatoes faster than the insides, leaving you with unevenly cooked taters. By the time they've fully cooked to the core, the outsides will be mushy and start to flake apart.
Too much — or too vigorous — mashing will produce gluey potatoes. Your best tool is an old-fashioned masher, fork, ricer or food mill. If you've already done the damage, turn pasty potatoes into a casserole: Spread them in a baking dish, drizzle with melted butter and sprinkle with grated cheese and breadcrumbs.
Tip #3: Don't Overcook or Undercook the Potatoes
If you overcook them they disintegrate and your potatoes will be soupy. The specific cooking time depends on the size of your potato: a perfectly cooked piece of potato should give no resistance when cut with a knife, but shouldn't crumble into a million pieces.
You don't have to cut potatoes to boil them, but smaller pieces of potato will boil faster than larger pieces. It will also be easier to work with smaller pieces if they will later become mashed potatoes.