Which components of egg white are responsible for foam formation?

Ovalbumin is the component of egg white which is responsible for foam formation.

Ovalbumin is the main protein component of the egg white and it is responsible for creating the foam structure when the egg whites are beaten. The physical stress caused by beating the egg white, causes the protein ovalbumin to denature and unfold. This denaturation, along with the mixing of air in the egg white, causes the formation of foam.