Why Do You Soak Potatoes in Water? 

Potatoes are one of the most versatile ingredients when it comes to cooking with substance.

Potatoes are considered a staple crop, supporting civilizations through time due to how easy of a crop it is to tend and how nutritionally dense they are. 

On Wikipedia there is a list of potato dishes that currently has 152 entries from around the world, and all but two of the dishes involve cooking the potato.

Thus comes probably one of the more time consuming parts of potato preparation which is soaking them in water. Why do you have to soak potatoes in water?

Potatoes must be soaked in water as soaking removes excess starch. Leaving on the potato starch will leave the preparation of a potato dish sticky, gooey, and inconvenient. Removing excess starch on potatoes allows for a more even, thorough cooking experience. 

Below is a guide on the why’s, when’s, and how’s of soaking potatoes. The task may seem time consuming, but it is necessary.

There will also be considerations for different kinds of potatoes in both type, dish, and cooking method. 

Why Do We Soak Potatoes in Water Before Cooking? 

We soak potatoes in water before cooking mainly to remove excess starch and moisture.

This eases the cooking process and creates a more hearty meal. Starch thickens when exposed to heat and cooking potatoes without washing away starch will cause them to stick to each other.

When potatoes are cooked, a chemical process called the Maillard Reaction occurs. During this process, amino acids and natural sugars react to create the browning color and comforting aroma.

If the starch isn’t removed, this can cause an imbalance in the reaction that leaves  spuds burnt.

Creating a cohesive, appetizing dish is not just a matter of preference. A 1977 nutrition study showed that more nutrients are absorbed from food that is actually desirable.

Thai women were presented two versions of a beloved rice dish, one of which was ground up into a paste.

Despite the two meals being chemically identical, more iron was absorbed from the meal that was more appetizing.

Can You Get Sick From Eating Raw Potato?

Raw potato can cause digestive issues if ingested in large quantities. Raw potatoes contain antinutrients and toxins which inhibit the body’s ability to break down other sources of nutrition.

Just as if someone were to eat raw grains or raw lentils, without cooking, the structure of raw potato isn’t conducive to proper human digestion which can cause gas and bloating.

Raw potato and potatoes that have been allowed to sprout and turn green contain a high amount of solanine.

Solanine is found in other nightshades as well such as tomatoes and eggplants. It’s a compound that causes symptoms like nausea, dizziness, nightmares, and throat burning if eaten in large quantities.

Raw potato, with the advisory of your doctor, can be eaten in small, medicinal quantities to promote gut health.

Raw potatoes contain a type of starch called resistant-starch that your gut fauna converts into a prebiotic. Resistant-starch also turns into butyrate which reduces colon inflammation. 

What Happens If You Don’t Soak Potatoes Before Cooking?

If you don’t soak a potato before cooking, the starches don’t get removed. While soaking potatoes can remove nutrients such as vitamin C and potassium, these nutrients can be made up for elsewhere in a balanced diet.

Not soaking a potato can lead to potatoes sticking together while boiling or even burning in the cooking process.

How Long Should Potatoes Soak in Water? 

Generally, potatoes should be soaked between 30 mins to 12 hours. However, the exact time potatoes soak for will depend on the dish being prepared as well as the size and type of potatoes.

Soaked Potato

If soaking a potato for any longer than an hour, it’s advised to refrigerate the container for the duration. 

Smaller types of potatoes, such as fingerlings, can be soaked for a shorter amount of time, but for at least 30 minutes. 

Large types of potatoes, such as yukon gold or russets, would need to be soaked for longer.

However, if larger varieties are cut into smaller pieces they do not have to be soaked as long.

Soaking larger potatoes for a longer period of time, such as overnight, would mostly be a consideration if the potato needed to remain intact.

Soaking Potatoes For Too Long.

Potatoes can be soaked for too long. All plant matter has a substance called pectin in its cell walls.

Pectin is a natural glue and structural component that is water soluble. When potatoes soak for too long, pectin starts to break down, causing the potato to become more gelatinous.

Smaller potatoes and potatoes that have been cut too small have their pectin dissolved faster, which is why they will need to soak for a shorter amount of time. 

Cut potatoes need to be soaked in water to remove the starch, and cutting larger pieces  smaller shortens the amount of needed soak time.

Starch is part of the entire structure of the potato, not just the outside, and cut potatoes allow more surface area for water to come into contact.

Soaking Potatoes Overnight.

Soaking potatoes overnight is fine as long as the potatoes are not in water for more than 24 hours.

After 24 hours is when the pectin starts to drastically break down and the potatoes will become nearly unusable. A 12 hour soak is a sufficient amount of time for most recipes. 

How Do You Soak Potatoes in Water?

Potatoes can be soaked in water by placing the portion in a bowl or pot suitable for large amounts of water.

The water should be cold and salted, and should cover all of the potatoes with at least an inch between the highest potato and the water’s surface.

Why Do You Soak Potatoes in Cold Water?

When preparing a potato, the goal of soaking is to remove excess starches.

Cold water, when mixed with salt (which will be elaborated on more in the next section), will pull the starch from the flesh of the potato.

Soaking a potato in warm water will actually activate the starch, causing the potatoes to become sticky.

Soaking in hot water runs this risk as well, and additionally could start the cooking process.

As briefly mentioned, if soaking for more than an hour, it’s advised to refrigerate the container to keep the water around the potatoes chilled. 

Why Do You Soak Potatoes in Salt Water?

Potatoes are soaked in salt water as a way to draw out moisture. Through a process called osmosis, water will leech out of the potato by being attracted to the ions in salt. If turning the potatoes into fries or hash browns, this will result in a crispier bite.

The salt bath should be prepared with cold water. The amount of salt added will depend on the goal of the dish and the size of the potato.

Some recipes that use whole potatoes suggest one cup of salt per six cups of water. Recipes for french fries using a pound of potatoes generally call for two tablespoons.

Potatoes should be soaked in salt water between 30 minutes to 12 hours, depending on the size of the potato and recipe.

Soaking the potato to get rid of the starch is a different function from using salt to draw out moisture. Both need to occur, so one can not be done without the other. 

Do Potatoes Cook Better If Soaked in Water?

Potatoes simply cook better when soaked in water properly and this means using cold, salted water.

As mentioned, cold water allows the starch to be pulled from the potato, and salt pulls out the moisture.

This has additional benefits when considering the mode of cooking, which are detailed below.

Air Frying

Potatoes should be soaked before air frying because of the way air fryers cook, in a process called convection.

The appliance heats the air in the basket, which is then evenly distributed through a rotating fan. In a regular oven (or conduction oven) the air within is just heated up.

By cooking fries or tater tots in the perforated basket of an air fryer, the entire surface that has been soaked and salted will be affected, as well as the inside.

The outside will get the trademark crunch that fried foods have and remain soft on the inside.

If the potatoes weren’t soaked beforehand, the potatoes could burn on the outside and be soggy on the inside.

Traditional Frying

Potatoes should be soaked and dried before frying as to avoid greasy potatoes. The key is that the potatoes need to be completely dry before frying so as to not send oil flying when the spuds hit the pan.

Frying Potatoes

Making sure the oil is hot enough also prevents greasy potatoes. 

The salt in the water bath also helps draw out moisture, resulting in an overall dryer potato. When pan frying or deep frying, the crispier bites come from dryer flesh.

This is why the outsides tend to crunch so much more-from more exposure to heat which evaporates moisture.

Baking and Roasting

Soaking a potato before it’s baked or roasted allows for a more thoroughly cooked potato in a conduction oven.

As mentioned, air fryers work through convection, and the difference with conduction ovens is the fan doesn’t play as much of a role.

Conduction works through heating the molecules in the air, which as the molecules move, creates friction and heats the molecule next to it.

When baking or roasting, the potatoes surface heats up and then cooks through. If a potato wasn’t soaked before being baked, the starch will burn.

The main differences between baking and roasting depend on the starting form of the dish, and the temperature at which it’s cooked.

Baking would be for more delicate dishes like au gratin, and roasting would be done with thick cuts of potatoes, oil, and spices.

The threshold for baking versus roasting is around 400°F (205°C).


The main consideration for soaking and boiling potatoes is to discard the soaking water, and refresh the boiling water.

Other Considerations

There are a few considerations to make depending on the dish and cooking method to maximize the flavor, texture, and tastiness of a potato. Here is some food for thought.

Soaking Potatoes for Mashed Potatoes.

When it comes to making mashed potatoes or a blended potato soup, salt water soaking is not as imperative.

Yes, it reduces the amount the potatoes stick together when boiling, but they will all end up being mashed anyway.

Any milk, butter, or substitutes of those will just reintroduce moisture back into the potato. 

If the soak is being skipped, the potatoes should still be thoroughly scrubbed to remove dirt and other contaminants.

Soaking Potatoes For French Fries.

When it comes to making french fries, soaking the potatoes in a salt bath shouldn’t be skipped.

Once the potatoes are sliced, they will have a proclivity to stick together if the starch isn’t washed off.

Additionally, the insides can possibly remain soggy after baking or frying due to excess water content.

Microwaving Potatoes.

Microwaving a potato is one of the times that a soak isn’t at all necessary. All the potato would need is to be washed to remove any dirt and debris.

After it’s dried, the potato should be poked a handful of times with a fork, optionally wrapped in plastic wrap, then microwaved for four to five minutes. 

Soaking Sweet Potatoes and Other Tubers.

Sweet potatoes should be soaked before cooking for the same reasons of soaking a potato.

Sweet potatoes actually have more starch than regular potatoes, so a longer soak would be in order. 

Other vegetables that should be soaked before use include parsnips, beets, turnips, jicama, maca, yuca, water chestnuts, and lotus root.

While the preparation technique should be investigated, tubers, or root vegetables, should usually be washed to remove debris before use.

Final Thoughts

Of course, every recipe, family tradition, and person is different. Which is to say, not soaking for an hour or forgetting to salt the water will not result in a bad dish.

Potatoes are a beloved tuber that have supported the world throughout history, so experimenting with what works for you and your tastebuds simply paves the way forward.

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