How Sugar Crystals Form

Appears in
On Food and Cooking

By Harold McGee

Published 2004

  • About

Sugar molecules have a natural tendency to bond to each other in orderly arrays and form dense solid masses, or crystals. When sugar crystals are dissolved in water to make a syrup, the water molecules overcome that tendency by forming their own bonds with the sugar molecules, surrounding and separating them from each other. If the dissolved sugar molecules in a syrup get too crowded for the water molecules to keep the sugars apart from each other, the sugars will begin to bond to each other again and form crystals. When the tendency of a dissolved substance to bond to itself is exactly balanced by the water’s ability to prevent this bonding, the solution is called saturated.