typified by the egg phosopholipid lecithin.
These are relatively small molecules with a
fat-like tail that buries itself in the fat phase
and an electrically-charged head that is
attracted to water molecules (p. 802). The
other kind of emulsifier is the proteins, which
are much larger molecules, long chains of
amino acids that have a number of different
fat-compatible and water-compatible regions.
The yolk proteins in eggs and the casein
proteins in milk and cream are the best
protein emulsifiers.
Unstable and stable emulsions. Oil and water
are incompatible substances; they can’t mix
evenly with each other. When oil is whisked
into water, the resulting oil droplets tend to