Egg Foams

An egg foam is a mass of air bubbles stabilized by a protein network — a structure unique to egg whites. When whisked, egg white proteins unfold at the air-water interface and bond into a continuous film that reinforces bubble walls, turning a liquid into a semi-solid that can hold its shape against gravity. This is the basis of meringue, soufflé, angel food cake, mousse, and many other preparations.