Mixtures of Phases: Solutions, Suspensions, Emulsions,
Gels, Foams
Cooks seldom deal with pure chemical
compounds or even single phases. Foods are
mixtures of different molecules, different
phases, and even different kinds of mixtures!
Here are brief definitions of mixtures that are
important in the kitchen.
A solution is a material in which
individual ions or molecules are
dispersed in a liquid. Salt brines and
sugar syrups are simple culinary
examples.
A suspension is a material in which a
substance is dispersed in a liquid in
clusters or particles consisting of many
molecules. Nonfat milk is a suspension
of milk-protein particles in water.
Suspensions are usually cloudy because
the clusters are large enough to deflect
light rays (individual dissolved