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How long to soak fries in salt water?

Fries are a delicious and popular side dish that can complement many meals. When making fries at home, soaking the potatoes in salt water before frying can help produce crispy fries with a salty, seasoned coating. But how long should you soak fries in salt water for best results? Here is a detailed look at soaking times for french fries and tips for getting perfect salty seasoned fries.

Why Soak Fries in Salt Water?

Soaking fries in salt water, also known as brining, serves multiple purposes:

  • It seasons the potatoes and infuses them with salt flavor.
  • It draws out some of the starch from the exterior of the potatoes to improve crisping.
  • It helps the potatoes stay moist and seasoned through the frying process.

The salt in the water penetrates into the outer layer of the potatoes. When the fries are fried, the salt infusion gives them a salty seasoned coating. The brining process also draws out some of the starch on the exterior of the potatoes which promotes better browning and crisping.

How Long to Soak Fries for Crispness

For best results, most sources recommend soaking cut fries in salt water for at least 30 minutes up to overnight in the refrigerator.

Here are general guidelines for salt water soak times:

  • 30 minutes – This quick soak will help draw out some starch and infuse salt flavor.
  • 1-2 hours – This is ideal for getting nicely seasoned and crispy fries.
  • Overnight – An overnight long brine will deeply season the fries.

Soaking for short periods under 30 minutes does not have time to properly penetrate and draw out starches. Longer soaking times between 1-24 hours will continue to draw out more starch for increased crispness and absorb more salt for seasoned flavor.

1-2 Hour Ideal Soak Time

Most recipes and chefs recommend shooting for a 1-2 hour fry brine time. This allows sufficient time for the salt water to soak into the potatoes and draw out excess starch, but is not so long that it over-seasons them or causes them to become mushy.

Kenji Lopez-Alt, author of the cookbook The Food Lab, did extensive testing on french fry brining. His studies found that around a 1-2 hour soak achieved optimal crispness and properly seasoned flavor.

How Long to Soak Thicker Fries

If you cut your fries on the thicker side, they may need a longer brine time.

Here are recommended salt water soak times for thicker fries:

Fry Thickness Recommended Soak Time
1/4 inch 1-2 hours
1/2 inch 2-3 hours
3/4 inch 4-6 hours

As the thickness increases, the brine time should be extended to allow for full seasoning and crisping through the whole fry. Extra time is needed for the salt solution to work its way into thicker potato cuts.

How Long to Soak Fries in Advance

Many cooks like to do the brining step in advance for convenience when it’s time to fry. Here are tips for advance brining:

  • Soak cut potatoes in salt water up to 24 hours before frying.
  • For brining 1-2 days in advance, store soaked potatoes in the refrigerator until ready to fry.
  • Pat potatoes dry before frying to remove excess moisture.
  • Increase oil temperature slightly to account for chilled potatoes.

The salt water will keep the potatoes nicely seasoned and ready for crispy frying for up to 2 days when stored in the refrigerator. Letting the brined spuds sit out at room temperature for more than 2-4 hours can start to make them mushy.

Salt Water Concentration

When brining fries, you can control the amount of saltiness by adjusting the salt concentration in the water. Here are common amounts used:

Salt : Water Ratio Description
1 tbsp per 4 cups water Gives a mild salt flavor
2 tbsp per 4 cups water Gives a moderately salty flavor
1/4 cup salt per 4 cups water Makes fries very salty

The more salt used in the brine, the more seasoned the fries will become. You can adjust the saltiness to suit your taste preferences. Some people prefer only a light salt flavor, while others like a strong salty punch.

Consider Frying Oil Saltiness

Also consider that any salt in your frying oil will further season the fries. If using salted frying oil, you may want to reduce the amount of salt in the soak water.

Soaking Creates Uniform Seasoning

An advantage of brining versus just salting fries after frying is it evenly seasons the whole fry. The salt water solution coats each fry and gets absorbed uniformly.

Simply sprinkling salt on after frying can create inconsistent seasoning, with some fries much saltier than others. Pre-brining ensures evenly salted flavor in each fry.

Double Frying for Crisp Fries

For extra crispy fries, double frying is recommended. After soaking and draining, first fry at a lower temp around 300°F until they are cooked through but not browned. Then let the par-cooked fries drain and rise in temperature before the second fry at 350-375°F to crisp and brown.

The initial fry cooks the potatoes, while the second higher-temp fry dehydrates the exterior for crisping. For soft fluffy insides and super crisp exteriors, double frying is the way to go.

Oven-Baked Brined Fries

While deep frying makes the crispiest fries, you can also bake brined fries with excellent results. Simply soak cut fries in salt water as usual before baking.

To oven-bake brined fries:

  • Preheat oven to 400°F.
  • Drain soaked fries and pat dry.
  • Toss fries in a bowl with oil to coat.
  • Spread fries on a baking sheet in a single layer.
  • Bake 25-35 minutes, flipping halfway through, until browned and crispy.

Baked fries won’t get quite as crispy on the exterior as deep fried. But brining helps provide seasoned flavor and some crisping even when baking.

Other Flavorful Brines

In addition to salt, consider adding other seasonings to your brine water for more flavor:

  • Garlic – Add smashed garlic cloves or powdered garlic
  • Onion – Soak fries with halved onion or onion powder
  • Herbs – Try rosemary, thyme, sage or other herbs
  • Spices – Chili powder, cayenne, paprika, curry, etc

Get creative with your fry brines! The salt water soaks up any flavors you add to give boldly seasoned fries. Change up your fry brine to create signature seasoned fries.

Troubleshooting Brined Fries

If you are having any issues with brined french fries, here are some tips to troubleshoot:

  • Potatoes too mushy – Don’t soak longer than 24 hours. Pat dry before frying.
  • Not crispy enough – Soak longer to draw out more starch.
  • Underseasoned – Use more salt in the brine water.
  • Oily taste – Use fresh oil at proper frying temperature.
  • Burnt taste – Lower oil temp slightly.
  • Uneven cooking – Cut fries evenly so they cook at same rate.

With the right timing, salt ratio, and frying temp, you can achieve perfectly crisped seasoned french fries from your salt water soak.


Soaking fries in salt water before frying is an easy way to boost flavor and texture. While soaking times can range from 30 minutes to overnight, a 1-2 hour brine is ideal for getting fries that are properly seasoned and crispy. Adjust salt concentration to control the salty flavor. For extra crisp fries, double fry after brining. With the right brine time and method, you can enjoy restaurant-quality seasoned crispy french fries at home.