How lollipops are made

A lollipop is sugar glass, and it only stays clear because corn syrup keeps the sugar from crystallizing.

stations: 6
things upstream: 9
raw sources: 5
steps from the ground: 3

The short version

A lollipop is a stick of hard candy made by boiling sugar and corn syrup with water until almost all the moisture is gone. The syrup cools into a glassy solid instead of crystals, with less than 2 percent water left. Flavor and color go in near the end, and the candy is shaped around a stick.

Dissolve the sugar

Sugar and corn syrup are stirred into water. Water is needed only at the start. The corn syrup is the ingredient that blocks crystal growth later.

Goes in
Sugar Corn syrup Water
Boil away the water

The syrup is heated well past the boiling point of water so nearly all the moisture leaves. Many hard candies are cooked to around 154 degrees Celsius, though the exact figure depends on the batch.

around 154 °C
Stir in flavor and color

Flavoring and dye go into the hot syrup. Extras such as a bubble gum center can be added as well, though they are not part of the basic structure.
Shape it on the stick

The thick hot syrup is formed into its shape while it still flows, with a stick set into it.
Cool into glass

As the candy cools it passes through the glass transition and goes hard without crystallizing. The finished moisture is only 1 to 2 percent, compared with 8 to 12 percent in crystalline candies.

1 to 2% water
Wrap each one

Each lollipop is wrapped to keep out humidity, because moisture from the air would make the glass sticky.

End of the lineLollipop

Worth repeating

One account says George Smith of New Haven started making hard candy on sticks in 1908 and named it after a racehorse called Lolly Pop.
Candy on sticks goes back to the Middle Ages, when nobles ate boiled sugar with the help of handles.
Some lollipops carry medicine, a way of giving children medicine without a fuss.