A scientific look at the power of eggs.
Chemically speaking, egg whites and egg yolks are quite different. Egg whites are about 90 percent water along with some protein. Egg yolks, on the other hand, have plenty of fat mixed in with their proteins.
This difference in their composition results in distinctly different properties and taste. When separated, eggs can make things as light and fluffy as a meringue or as rich and decadent as pastry cream.