On Food and Cooking

causes the storage proteins to bond to each
other, and breaks apart some of the corn oil
into excellent emulsifiers (monoand
diglycerides). After steeping, the soaking
solution and softened hulls are washed away,
and the kernels, including the germ, are then
stone ground to produce the dough-like
material called masa. Stone grinding cuts the
kernels, mashes them, and kneads the mass,
mixing together starch, protein, oils,
emulsifiers, and cell wall materials, and the
lime’s molecule-bridging calcium. With
further kneading, this combination develops
into a cohesive, plastic dough.
The convenience form of masa is masa
harina, a flour made by flash-drying freshly
made masa into small particles. Because it’s
made with less water than normal masa and
then is dried, masa harina has less masa
aroma and an added browned, toasty aroma,
and produces a softer texture than fresh masa.