How to make crispy/dry potato chips/crisps?

I am going to get "unsciency" as I used to make fries for hours on end at a local mom and pop shop.

How thin / thick doesn't really matter, you'll just have to adjust your frying time accordingly.

1) Use a starchy potato

2) slice your potato evenly, with a peeler if you don't have a slicer or mandolin

3) soak them in water for 30 mins with a pinch of salt

4) let them dry a bit

5) blanch them with vegetable oil until they are limpy but has no visible color change (Oil should be hot enough that when you put them in, 5 seconds later there are bubbles)

6) cool them completely, I throw them into a container into the fridge

7) refried them by putting in enough pieces in such that it will still bubble immediately (oil should be hot enough when you drop a spot of water or chop sticks in that it bubble immediately, but you wouldn't hear like a crackling or have oil splashing at you)

8) Take them out one piece at a time as they change color.

The key is vegetable that's pretty much the only oil that makes things cripsy at lower frying temperature, other than bacon fat, this makes a much more golden chip, and generally a easier time to control, so you can make more at the same time. Shortening, olive oil, peanut oil, butter, lard has been tested and isn't really good. Sesame oil is good too if you like the taste of it. Also, don't attempt to drain the oil after blanching, the oil will come out when you re-fry them.

Salt or season while warm.

Kenji Lopez-Alt has published one of his magnificent Food Lab articles on the potato chips, with the goal of light colored potato flavor like his favorite brand, while having the robust crunch of kettle chips.

He points out that when fried, potato chips undergo several processes:

• They dehydrate
• Oil enters the empty spaces left by water
• Sugars, starches and proteins undergo browning reactions, creating flavor—but too much of this leaves a burned or off taste

Potato chips are so thin (Alt finds a 1/8 inch, or 0.3 cm thickness done on a mandolin for uniformity ideal) that it is difficult to get them crunchy without leaving them also over browned and bitter.

In order to remove extra sugars and starches, to limit browning, Alt recommends the same technique he developed for French fries: blanching in water acidulated with vinegar. They are then dried, and deep fried. The vinegar allows the potatoes to maintain their shape during the blanching.

Once blanched, the chips are dried, and then deep fried in a fairly traditional manner.

See his recipe for details.

Note that the Frito Lay page on how they make their own chips indicates a similar technique: thinly sliced potatoes, rinsed to remove extra starch, and then "cooked to a crispy crunch in all-natural oil" which I take to mean deep fried.

Commercial potato chip makers like Frito Lay use significantly different ovens than residential ovens. They also prepare the potato chips differently. From what I understand Pringles for example starts with something similar to mashed potatoes. For example (from Modernist Cuisine):

Adding 0.5% of Methocel K100M by weight of slurry can reduce the oil uptake of the chips after frying by up to %20.

you can however, make nice kettle chips at home using this recipe or similar. It typically does involve double frying.

If I were to attempt to make chips similar to commercial ones (haven't recently) the process would go as follows:

1. Slice the potatoes
2. Blanch them (a few seconds in boiling water, then ice water). This should stop the enzymatic browning for next step.
3. Put the chips in a dehydrator for a few hours (1-2).
4. Spray with oil.
5. Bake in a convection oven at 350F on a wire-rack till done.

Keep in mind that Potato chips are technically a form of glass as far as the physics classification is concerned. The dehydration step is there to make the chips less soggy and more crispy (closer to glass since).

updates: Regarding the potato chip 'glass state of matter' note. It refers to the suspended crystalline structure of the starches in the potato chip. I first heard it from Nathan Myhrvold. There are also 'glass potato chip' recipes out there in the wild.

There is a section on making fruit and vegetable chips in Volume 3 (pg 323-331) of Modernist Cuisine, if you're interested. Having looked at it now, the process is similar to the recommendation above (including the dehydrator) but suggests sous vide cooking the chips at low temperature and frying in oil in the end.

As I do.

Homemade are never as thin as those bought, unless you use a slicing machine.

• Wash the potatoes to remove excess starch.
• Dry them well.
• Use lots of oil, very hot.
• Put potatoes in the pan a few at a time, so they do not overlap.
• When just they have taken color, turn them on the other side.
• Lower the heat.
• The cooking time depends on the thickness, are more subtle and less time is needed.
• Just golden on both sides, drain them out the oil and put them on a plate where you have arranged 3-4 sheets of kitchen paper.
• Raise the fire.
• Put other potatoes in the pan and proceed the same way.
• Sprinkle the freshly made with very little salt, cover with other sheets of kitchen paper, for the next potatoes, and cover with a plate or bowl upside down, so that they retain the heat.

When they all are ready, press a little with hands, because the paper towels to absorb all the oil. Put them on a platter, on which you put a paper towel, and take them immediately on the table, still warm.

I made sweet potato crisps by cutting with my potato peeler, then putting them in my deep fryer, make sure its very hot, a few seconds latter they are ready. They were lovley.