An emulsion can only be made from two
liquids that don’t dissolve in each other, and
therefore retain their distinct identities even
when mixed. The molecules of water and
alcohol, for example, mix freely and so can’t
form an emulsion. In addition to sauces,
cosmetic creams, floor and furniture waxes,
some paints, asphalt, and crude oil are all
emulsions of water and oil.
The Relative Proportions of Fat and
Water in Common Food Emulsions
Food Parts Fat to 100 Parts Water
Fat-in-Water Emulsions
Whole milk 5
Half-and-half 15
Light cream 25
Heavy cream 70
Heavy cream reduced by a third 160