On Food and Cooking

beaten into 1 egg yolk plus water gives a
sparse emulsion of coarse, unevenly sized oil
droplets (left). Eight tablespoons/120 ml of oil
give a tightly packed, semisolid emulsion of
small droplets (right). The yolk emulsifiers
and stabilizing proteins must be effective
enough to withstand considerable physical
pressure in order to prevent the oil droplets
from coalescing into a separate layer.
Making Billions of Droplets from One
Tablespoon It’s on account of surface
tension, then, that the cook must pour energy
into the liquid to be dispersed. To make a
sauce, its natural monolithic arrangement
must be shattered. And seriously shattered:
when you beat a single tablespoon/15 ml of
oil into a mayonnaise, you break it up into
about 30 billion separate droplets! Serious
whisking by hand or in a kitchen mixer
provides enough shearing force to make
droplets as small as 3 thousandths of a
millimeter across. A blender can get them