On Food and Cooking

and thicker. Salt breaks apart the light-
deflecting sub-spheres into components that
are too small to deflect light — and so the
yolk clears up.
And what do the subspheres contain? A
mixture similar to the liquid that surrounds
them in the spheres. First, water. Dissolved in
the water, proteins: hen blood proteins outside
the subspheres; inside, phosphorus-rich
proteins that bind up most of the egg’s iron
supply. And suspended in the water, sub
subspheres about 40 times smaller than the
subspheres, some of which turn out to be
familiar from the human body. The
subsubspheres are aggregates of four different
kinds of molecules: a core of fat surrounded
by a protective shell of protein, cholesterol,
and phospholipid, a hybrid fat-water mediator
which in the egg is mainly lecithin. Most of
these subsubspheres are “low-density
lipoproteins,” or LDLs — essentially the same
particles that we keep track of in our own