Egg white foams are almost always made with
other ingredients, and these can influence the
beating process and the final consistency.
Salt Salt increases the whipping time and
decreases the foam’s stability. Salt crystals
dissolve into positively charged sodium and
negatively charged chloride ions, and these
probably compete for bonding sites on the
unfolded protein molecules, thereby reducing
the number of protein-protein bonds and so
weakening the overall structure. It’s therefore
best to add salt to the other components of a
dish — the base of a soufflé, for example —
rather than to the foam itself.
Sugar Sugar both hinders and helps foam
making. Added early in the process, it delays
foaming, and it reduces the foam’s ultimate
volume and lightness. The delay comes from
sugar’s interference with the unfolding and
bonding of the proteins. And the reduction in
volume and lightness is caused by the syrupy