Q How are gummy bears made?
— Kai Sampson
A Rich Hartel, professor in the department of food science at the University of Wisconsin-Madison:
Gelatin is the basis of what makes a gummy bear a gummy bear, but first it starts with sugar, corn syrup and water.
Food scientists use water to help the sugar dissolve but then heat the mixture to about 240 degrees to boil off the excess until the mixture is only about 12 percent water.
Then gelatin is added and dissolved into the mixture. Gelatin comes from the hooves and skin of pigs or cows and is basically collagen broken into smaller molecules.
Think of a tough or grisly meat steak — that’s collagen. When you add heat, like putting meat in a crock pot for an extended period of time, the collagen breaks down and is easier to eat.
In the same way, we dissolve the gelatin into the sugar and corn syrup mixture for gummy candies. We then add color, flavor and a little bit of acid.
To make the gummy bear shape, we press a form of the bear shape into a tray of corn starch. The corn starch has a little more oil in it than you would find at the grocery store, so it holds its shape when we press the bear form into it.
We then fill the holes with the liquid candy mixture and let them dry overnight. The gelatin will cool, and the corn starch takes more moisture out of the candy to get it to its final gummy state.
One interesting property of gelatin is that it’s thermo-reversible, meaning that heat can turn it back into a liquid. If you put a gummy bear in the microwave, you’d see this in action, and the gummy would turn liquid. When it cools down again, it resets back into a squishy gel.
This is based on the chemical nature of the gelatin molecule. You can go back and forth a number of times before the gelatin loses its elastic properties.