Egg-Yolk Foams

Though almost half water, the yolk contains more protein than the white does, as well as all the egg’s fat. It is therefore apparent that a yolk has less ability to foam to any great volume than the white since it contains so much fat. As you whip egg yolks, it is easy to guess the amount of air you incorporate because the color lightens. The addition of sugar, depending on the amount, can affect the whipped yolks’ color and thickness, but you still cannot overwhip egg yolks as easily as you can egg whites. Though the fat decreases the chances for an enormous increase in volume, it stabilizes the foam so that when you make a cake, you can whip the yolks before the whites and let them stand without fear of losing too many air bubbles.