Yolk

Egg yolks are about half moisture and half yolk solids. The solids in egg yolks consist of proteins, fats, and emulsifiers (Table 10.1), with small amounts of mineral ash and yellow-orange carotenoids. Egg yolk proteins are not the same as egg white proteins, but like egg white proteins, they are important structure builders in baked goods. Many egg yolk proteins are lipoproteins, proteins bound to lipids—that is, fats and emulsifiers. It is because of these lipoproteins and emulsifiers that egg yolks are superior at emulsifying foods.