On Food and Cooking

The structure of the hen’s egg. The egg white
provides physical and chemical protection for
the living germ cell, and protein and water for
its development into a chick. The yolk is rich
in fats, proteins, vitamins and minerals. The
layering of color in the yolk is caused by the
hen’s periodic ingestion of grain and its fat-
soluble pigments.
What’s inside these large yolk spheres?
Though we think of the yolk as rich and fatty,
in fact its chambers are filled mostly with
water. Floating in that water are sub-spheres
about one hundredth the size of the spheres.
The subspheres are too small to see with the
naked eye or to be broken up by a kitchen
beating. But they can be seen indirectly, and
disrupted chemically. Yolk is cloudy because
these subspheres are large enough to deflect
light and prevent it from passing through the
yolk directly. Add a pinch of salt to a yolk (as
you do when making mayonnaise) and you’ll
see the yolk become simultaneously clearer