What makes rock candy sticky when you eat it?

Rock candy is not sticky when you first put it in your mouth, but it eventually becomes sticky as you suck or chew on it. This stickiness is caused by the dissolution of the sugar crystals in the candy. As the sugar crystals dissolve, they release water molecules, which are attracted to the surface of your tongue. This creates a thin layer of water between the candy and your tongue, which makes it feel sticky. The stickiness of rock candy can also be increased by the presence of saliva, which contains mucus that helps to bind the sugar crystals to your tongue.