By Carolyn Robbins
Updated Mar 24, 2022
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When you hold a spoonful of sugar, you’ll notice its white texture is actually a lattice of countless tiny granules. In water, these granules dissolve, yet they can be coaxed back into crystalline form through two well‑understood natural processes.
In a crystalline lattice, sugar molecules are most stable. When a sugar solution is left uncovered, water evaporates, concentrating the solution. As the solvent disappears, sugar molecules are forced together, re‑forming the orderly crystal structure. This gradual, surface‑driven growth is why a shallow pan of syrup will eventually solidify into a sugar “cane” as the steam escapes.
Cold water can dissolve only a limited amount of sugar. Heating the solution increases its capacity to hold sugar molecules, creating a supersaturated state. When the hot solution cools, the excess sugar can no longer remain dissolved and precipitates out, arranging itself into crystals. This technique is employed in candy making, where a sugar syrup is boiled and then cooled to produce the perfect granularity.
