The fries are perhaps the most international culinary preparation. This invention is usually dated between the late seventeenth and eighteenth centuries. The paternity of french fries constitutes a historical dispute between France and Belgium – which then, it must be said, was Spanish – but the truth is that they must have appeared as soon as the potato became popular in Europe, as frying was already a cooking widespread on the continent.
To make perfect French fries, you only need two things: good oil and good potatoes. But despite its simple preparation, most homes and restaurants choose to serve frozen potatoes, to make frozen french fries in air fryer which is much more convenient.
To make perfect French fries, it is necessary to fry these – at least – in two times, an essential condition so that they are crispy on the outside and soft on the inside. The frozen potatoes have been previously pre-cooked so that we can save the first frying. But, of course, they are not nearly as good.
Frozen French Fries in Air Fryer
To make good French fries, it is essential to know the process that occurs when we submerge them in boiling oil.
When we fry a potato – or any other food – the moisture on its surface evaporates immediately. Its exterior remains dry, and a hard crust soon forms. Inside that shell, the temperature increases enormously. The water vapor that did not reach the surface before the crust formed is trapped, cooking the interior.
The contrast between a crunchy coating and a soft interior is the secret of any good frying. And to achieve this, the outer crust must form immediately. Otherwise, the water would be released entirely, and the food would remain dry. Naturally, most foods cannot create a solid crust quickly enough, that’s why they are coated: the starch in the flour hardens speedily and, also, has the potential to caramelize, something key to achieving the sweet note we are looking for in any frying.
French fries are never battered because the tuber itself contains a lot of starch. All you have to do to fry a potato well is to fine-tune the process by which the crust is formed, and the interior is steamed. Something simple but that has occupied chefs from all over the world for centuries.
How to make perfect French Fries
Most cooks make their fries with a double fry: the first one at a relatively low temperature and a second with high heat. As J. Kenji López-Alt explains in a comprehensive blog post on The Burger Lab , frying potatoes for the first time changes the exterior structure. Part of the water evaporates and the starches, which are released thanks to the oil’s heat, combine with what remains, forming gelatin. This jelly seeps out and hardens the edges of the potato. In the second frying, this gelatin creates a thicker and crunchier crust, which is the perfect potato’s secret.
Double frying seems somewhat complicated, but it can be done correctly at home, following these simple steps:
1. Peel and cut the potatoes into sticks
Which size? This is a matter of taste, but the standard dictates that they must have a length of between 7 and 15 centimeters (something that depends, of course, on the potato) and a thickness of one centimeter. In any case, all chefs cut French fries by eye: it is not something that has a decisive influence on their delicacy. Unevenness is one of the things we look for in an excellent homemade potato chip.
2. First frying
The ideal temperature for the first frying is approximately 140ºC. How do we calculate this if we don’t have a deep fryer? A simple trick is to toss a bread crumbs into the pan. If it falls to the bottom, the oil is not too hot. Add the potatoes little by little. It is essential not to add too many potatoes simultaneously, as they must be well coated in oil and not stacked one on top of the other. When adding the potatoes, the temperature lowers, so it is best to make the potatoes in several batches. The potatoes should be removed when they are slightly browned, but not quite fried.
Once the first frying is done, you must let the potatoes cool before starting with the second, so that the jelly we talked about before is well-formed. In this phase, some cooks put the potatoes in the freezer for about 20 minutes, as contact with the cold makes the potato compact and takes on more body for the next frying.
4. Second frying
On this occasion, the oil has to be at a temperature of 180º. If we don’t have a thermometer, we can use the breadcrumb trick again, but it must float to the surface. Add the potatoes also, batches, and fry for at most two minutes until they are very crisp. Remove them on kitchen paper so that it absorbs the excess oil and adds the salt immediately.
Excellence: triple cook potatoes
In the 90s, British chef Heston Blumenthal, owner of the famous restaurant The Fat Duck, became obsessed with the search for the perfect potato chip: he tried hundreds of varieties of potatoes, experimented with drying them, microwaving them and even working each cut separately. In the end, he found a recipe that made it possible to create potatoes “with a glass-like crust and a soft and fluffy center.”
The secret of the Blumenthal recipe lies in adding a previous step to the classic double frying process. The British chef first boils the potatoes in water for 20/30 minutes until, practically, they are falling apart and have many cracks on the surface. If we put the potatoes like that in the fryer, they would melt completely. What Blumenthal does before frying them is to remove all the moisture using a vacuum machine.
This pre-cooking has three objectives: to cook the potatoes gently, so that the texture inside is more fluffy; create cracks that allow oil to enter, which makes the potatoes crispier; and finally, thanks to the vacuum machine, eliminate all the humidity, which according to the chef is the great “enemy” of French fries.
After this, the cook fries the potatoes at 130ºC for 5 minutes and puts them back in the vacuum machine. Finally, fry the potatoes at 180ºC for about 7 minutes until they are golden brown and crisp.
If you want to experiment with this technique at home and you don’t have a vacuum machine, you can freeze the potatoes. The result is practically the same.