The potato: simple, plain, grown in the earth, a side dish to many mains. But also the fundamental element of one of the world’s most treasured comfort foods — the french fry. However, not all potatoes are created equal when it comes to perfecting the fry.

The perfect fry, for the purpose of this science lesson, equals crispy and golden on the outside and soft (but cooked) on the inside. But this end game can be achieved only with the perfect beginning. Quality potato selection is imperative to making the perfect fry.

The most popular potato for french fries in the United States, home of fast food, is the russet — the primary potato used by McDonald’s. Most commonly used is the Russet Burbank, but McDonald’s also uses several varieties of russet for its fries.

If you can’t locate these in your local supermarket, you’ll want to find a potato that is high in starch but low in moisture. The starch achieves caramelization, resulting in a crispy exterior, and low moisture ensures you won’t be left disappointed with soggy fries. But remember, the higher the starch content, the darker the fries are likely to be.

The Russet Burbank is also popular due to its nutritional value.

This apple of the earth is loaded with vitamins C and B6 and is high in antioxidants. And if you’re looking for protein, fiber and iron, the peel-on fry is the way to go.

Now that you’ve acquired the perfect potato, it’s time to select the perfect oil.

There are factors to consider when choosing the right oil for cooking french fries. The correct oil can affect the texture and the flavor of your finished product.

Thermometer manufacturer ThermoWorks recommends oil that has no flavor as it can transfer to your food. The oil’s ability to take the heat also contributes to flavor.

---

Smoke point is how the oil behaves when exposed to high temperatures. If the oil has a low smoke point, it will burn at high temperatures and transfer the burnt flavor to your fries. So choose an oil that has a higher smoke point.

Oils with higher smoke points are those that are refined (processed) like avocado oil, canola oil and peanut oil. While avocado oil has the highest smoke point at about 510 degrees Fahrenheit, it seems peanut oil is the winner of the oil contest with its lower saturated fat levels, richness in vitamin D and smoke point of 450 degrees Fahrenheit. It is also the chosen oil of U.S. restaurant giant Chick Fil A

 

IMAGE CREDIT: Unsplash

Now that the shopping is done, it’s time to prep and get cooking.

To soak or not to soak?

It really depends on whether you like your fries dark or golden. Soaking your cut fries for 1-2 hours will reduce the amount of sugars on the outside, allowing for golden crispiness, but not soaking will result in more caramelization and leave your fries much darker. It can also result in burning. The blanching process can also reduce the amount of nutrients remaining. And the thicker they are, the longer you’ll have to cook them.

Your preference for french fry thickness will determine the length of time on the cook as it also dictates the time it takes for the heat to reach the center of the fry.

The fry: once or twice? And what is the point?

The double fry seems to be a popular method of achieving a thicker, crispier and more stable outer layer with a soft inside. The first fry is at lower heat (325 degrees Fahrenheit) and the second fry is done at a higher heat (400 degrees Fahrenheit). Potatoes have two types of water molecules, those that are bound tightly to the potato and those that are loosely bound. During the first fry, the hot oil evaporates the loosely bound molecules and mobilizes the starch to form an outer covering, protecting the fry from drying out. The second fry is to achieve the golden, crunchy goodness.

Now that you’ve achieved a french fry work of art, the final stroke is the topping of your choice and celebrating National French Fry Day the way it was intended.

The french fry market in 2021 was valued at U.S.$16.2 billion globally and is expected to grow to U.S.$22.9 billion by 2029.