[Narrator] Play-Doh.

It's your childhood in a yellow, plastic tub.

Smooth and pliable.

Moist, but not sticky.

Tastes salty.

Smells sweet.

What's inside this magic dough?

It starts with flour and water.

Warm water breaks down starch in the flour,

which makes the mixture thick and viscous.

But as it cools, water evaporates.

Ordinarily the starchy bits would cling together and harden.

Not fun.

That's where amylopectin comes in.

The starch has hidey-holes for water molecules

that keep the dough moist and pliable.

Mineral or vegetable oil,

and a white, waxy substance called P-E-G 1500 Mono Stearate

keep the texture smooth.

Play-Doh is actually about 10% salt,

10 times saltier than your typical bread dough.

It binds up any free water,

and it's the first thing you notice, if you take a bite,

right before the bitterness hits.

That's aluminum sulfate,

added to keep the kiddos from seriously chowing down.

It's also a preservative,

which along with household cleaner borax

prevents mold and bacteria growth.

What about the smell?

That sweet aroma that sends you straight back to preschool.

Vanilla is Hasbro's only hint,

but the real formula for their signature scent

is guarded like the recipe for Coca-Cola.

But we're fine with a little mystery.

Just don't get the colors mixed up, okay?

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