Reverse Engineering the McDonald’s French Fry

McDonald’s is serious about their fries. When they were forced by shifting public opinion (drunkenly swaggering around as it always does) to switch from their beef tallow and cottonseed oil mixture to a vegetable oil mixture; they spent millions to find a solution that retained the taste. How they make the fries is not the worlds most closely guarded secret, but they do have a unique flavor, texture, and appearance which is a product of lots of large scale industrial processes. [J. Kenji López-Alt] decided to reverse engineer the process.

His first problem was of procurement. He could easily buy cooked fries, but he needed the frozen fries from McDonald’s to begin his reverse engineering. McDonald’s refused to sell him uncooked fries, “They just don’t do that,” one employee informed him. He reached out to his audience, and one of them had access to a charlatan. The mountebank made quick work of the McDonald’s employees and soon [J. Kenji] had a few bags of the frozen potato slivers to work with.

What follows next was both entertaining and informative. At one point he actually brought out a Starrett dial caliper to measure the fries; they were 0.25in squares in cross section. Lots of research and experimentation was done to get that texture. For example, McDonald’s fries aren’t just frozen raw potatoes. They are, in fact; blanched, flash fried, frozen and then fried again. Getting this process right was a challenge, but he arrived at similar fries by employing his sous vide cooker.

He then wanted to see if he could come up with a french fry recipe that not only allowed the home chef to make their own McDonald’s fries, but improve on them as well. It gets into some food chemistry here. For example he found that the same effect as blanching could be produced by boiling the fries; if you added vinegar to keep the cell walls from disintegrating.

The article certainly shows how knowledge of the chemistry behind cooking can improve the results.

Satellite dish solar cooker bakes potatoes and more


Hone your survival skills by harnessing the sun’s rays to cook your meals. [Robert] and his daughter turned an old satellite dish into a solar cooker. The image above shows them baking some potatoes, but the temperatures inside the cast iron vessel are high enough to let you cook most foods.

The dish was originally used for satellite television but has been collecting dust in the shed for quite some time. When [Robert] came across a roll of foil tape in his workshop he decided to give the project a whirl. His daughter helped out by peeling away the tape backing (this can be much harder than it sounds) while he applied the reflective material trying to keep it free of wrinkles. After a close call [Robert] donned a pair of welding goggles when positioning the dish. If the light intensity can get the pot up as high as 428 degree Fahrenheit we’re sure it can cause flash blindness.

Unlike other dish cookers we’ve seen, [Robert] didn’t use the original mount for holding the dish in place. He just set it on three bricks and directed it by hand. To keep the intensity focused on the kettle he had to reposition it every 15 minutes.

We wonder if the heat is too much for building a sun tracking solar power harvester?

This GLaDOS potato is a lie

Why settle for virtual reality when you can make the digital world into reality? [Josh] wanted to have a GLaDOS potato accompany him through life when not playing Portal 2. He set to work to see what kind of replica prop he could come up with. Judging from the image above, and demo video after the break, he nailed it right in the spud.

There’s no worrying about rot. The potato and a few parts were molded from Sculpey and baked in the oven. Since the fake spud is hollow in the center it’s easy to hide the bits that make it talk. An old MP3 player was loaded with quotes from the game, and plays them back via an LM386 audio amplifier circuit and a speaker hidden below the electronic eye. The eye is lit by five yellow LEDs which are also tied into the amplifier to make them blink and fade with the intensity of the audio signal.

A paint job and the nails and wire really make the build look just right. Now [Josh] needs to host a geek-themed Halloween party so he can really show this off.

Continue reading “This GLaDOS potato is a lie”

Double barreled air cannon

[Jeremy] wrote in to show off his latest creation. he has built a two barrel pneumatic air cannon. Eschewing the traditional approach of having a single barrel and pressure chamber for his spud gun, [Jeremy] wanted to have a double barreled version. Since he was doing this pneumatically, he had to rig up a way to maintain pressure in each barrel independently of each other, as well as trigger them independently. While we can all agree that one way valves and sprinkler valves aren’t ground breaking, it is nice to see it all laid out and tested. We now have the blueprints if we were so inclined to create our own version.  You can see him testing it out by filling the chambers with water and sploooshing that all over the place after the break.

Continue reading “Double barreled air cannon”

Perfect spiral, every time

[Carmine] let us know about his team’s Automated Football Launcher. Their goal was to combine a football launcher with motion tracking, to allow a player to practice running and catching with the perfect throw. Unfortunately, and we’re not quite sure when, they ended up changing out the Jugs machine for an air cannon, which resulted in the use of foam footballs and the loss of throwing factors such as spiral. Somewhat defeating the purpose but we’ll let it slide; only because we know its going to be shooting potatoes eventually.

The project comes together by using two cameras giving distance and color tracking, combined with a rotating platform (and the best use of garden hose ever), an accurate set-top for their launcher. As seen in the video after the jump, it works out quite nicely. Continue reading “Perfect spiral, every time”

Sausage Gun 19mm

If you are anything like us, you find yourself needing, on occasion, to fling sausages at high velocity. [F00] sent in his solution, the SG19. While the details are glazed over pretty quickly, we get the point. This is basically a smaller diameter spud gun, meant to shoot sausage. While it may not be remarkable in its design, we have to wonder who came up with the idea to use sausage as the ammunition.

Steam powered spud gun

[robbtoberfest] put together this cool looking steam powered spud pistol. Made from household materials, like a lighter and some copper pipe, this spud gun builds pressure in its little bitty boiler to expel the projectiles. It seems as though he’s using a cork to supply a seal, so why bother with potatos? At roughly 2 minutes between shots, its not the quickest, but it sure is cool. Good job [robbtoberfest].