On Food and Cooking

temperature. The rapidly moving water
molecules in a hot sugar solution can keep
more sugar molecules dissolved than the
sluggish water molecules in a cold solution
can. The moment that a hot and saturated
solution begins to cool, it becomes super
saturated. That is, it temporarily contains
more dissolved sugar than it normally could at
that temperature. And once the solution has
become supersaturated, the smallest
disturbance will induce sugar crystals to form
and grow. As the sugar molecules gather into
solid crystals, they leave the solution around
them less concentrated. When the solution
reaches the sugar concentration appropriate
for its new temperature, the sugar crystals
stop forming and growing. The sugar is now
in two different states: some remains
dissolved in the syrup, and some is packed in
the solid crystals surrounded by the syrup.
There are two steps in sugar
crystallization: the formation of crystal