How Cotton Candy Works

Spun Sugar: Sweet Science

Other Candies Made from Sugar Alone

Cotton candy isn't the only pure-sugar sweet. With the help of added colors and flavors, a simple syrup produces a variety of results:

  • Fondant is granulated sugar that's boiled, poured out to cool and beaten until thick and smooth. It's then kneaded to achieve a plastic consistency. After a few days of resting or "ripening," fondant can be shaped into decorations or rolled into sheets to cover cakes.
  • Maple candy is maple syrup that's boiled and poured into candy molds to harden. It may be creamy or crunchy, depending on the temperatures at which it was cooked and cooled.
  • Pulled candies are stretched, either by hand or machine, before they're completely cooled. The process incorporates air, which gives a brittle consistency and a "holey" appearance. Taffy and candy canes are pulled candies.

Before cotton candy existed, there was spun sugar, but before people could "spin" sugar, they had to caramelize it.

Caramelization is what happens when sugar melts. A crystal of granulated sugar, scientifically called sucrose, is held together by chemical bonds, but energy from heat can break these bonds, splitting the crystal into its two component sugars, glucose and fructose. These sugars break down further, freeing their atomic building blocks: carbon, hydrogen and oxygen. Hydrogen and oxygen atoms reunite to form water, and the carbon clusters in increasingly larger clumps. Eventually the water evaporates and the carbon starts to burn.

However, if you stop this process while the sugar is still a liquid, you can make spun sugar. Pastry chefs in 15th-century Venice created masterpieces with spun sugar. Using forks, they drizzled the golden syrup onto a broom handle, and then worked the warm, pliable threads into different shapes and even entire scenes. Their artistry decorated plates of preserved fruits and other desserts. Spun sugar was a treat for the wealthy -- the two essential ingredients, sugar and time, were luxuries for most people. Spun sugar is still made today, but modern recipes include cream of tartar and corn syrup, ingredients that help prevent recrystallization.

Spun sugar was a precursor to cotton candy -- modern cotton candy would have to wait for the technological advances of the Industrial Revolution and the teaming of two unlikely business associates.