Throwing Spaghetti at the Wall

Posted on July 15, 2013


“Throw it at the wall and see what sticks.” It’s a common expression that means “you never know unless you try” or “hey, let’s give a bunch of these ideas a try—one of ’em might work.” But like going al dente, the wall test is an actual, real-life way to see if your pasta is ready to eat. Who the heck figured out that if you throw spaghetti at a wall, and it sticks, it’s done? Wouldn’t that indicate that it was wallpaper paste?

Paste and pasta really are not too different, down to the way they’re spelled. Paste is made with water and starch (glue is different in that it is made with animal proteins). Spaghetti pasta starts with starchy semolina flour, to which water is usually added. So with spaghetti, we have dried paste that is officially edible, unlike the bland nontoxic goo some adorable children consumed in kindergarten. Perhaps those kids had very advanced palates—or maybe they just liked Italian food?

And yet there’s a big, rudimentary difference between paste and spaghetti: one is intended to be eaten for dinner. Paste is already gooey when you buy it, and ready to stick, whereas most Americans are used to buying hard, dried pasta. The pasta stays hard until placed in boiling water; then the dried pasta absorbs some water and tries to reconstitute itself back into dough. The boiling water fills in the inherent gaps in the spaghetti strand, causing the spaghetti to swell much like the way a dry sponge becomes flexible when its holes are filled with water. This produces an effect that scientists call “yummy.”

Imagine the strand of spaghetti is like a series of train cars lined up to form a long train. The train would be the polysaccharide chain in the pasta. Then there is an enzyme fitted between the train cars like a hitch. The boiling water is like a mallet used to knock the hitch-pin out from between the cars, which separates the cars. These combined actions are known as hydrolysis. After hydrolysis takes place, the rigid polysaccharide train becomes a strand of sticky, simple carbohydrate monomers, which are now much more flexible and fluid.

The stickiness extends to the surface of the pasta noodle, and this malleable, pasty strand now has the ability to stick to the surface of a wall with the help of a starchy residue coating the noodle. At home, where you probably don’t fling it at the wall, you probably move the cooked spaghetti from its strainer fast. Otherwise the starch will glom the cooked noodles into a rubbery colander mold that bounces when it’s dropped.

Who chucked the first noodle at the wall? We’ll likely never know. Maybe they were related to the person who figured out you could grind up wheat seeds into fine flour, roll it with water, and make long, edible floppy things that taste good with marinara sauce.

As for the classic saying itself, it’s a fabulous cliche that casually describes the trial-and-error method of problem-solving and idea-testing. The phrase does have its limitations, though: in real life, overcooked pasty pasta will cling to the wall just like a properly cooked noodle. At least you’ll know it’s done enough to be food, not paste.

Kiped from the archives of the SyFy channel’s IdeaLab Blog for the TV show Eureka. Well kinda kiped, since I wrote it to begin with. Edited by Tiffany Lee Brown, without whom I’d be stuck in the land of curly quotes.

Posted in: science, writing