What alkaline process is used to prepare corn for masa and tortillas?

What alkaline process is used to prepare corn for masa and tortillas? Nixtamalization.

Nixtamalization is the alkaline cooking and soaking of maize, usually in limewater, followed by washing and removal of the loosened hull. The treated kernels, called nixtamal, can be ground into masa for tortillas and many other foods.

This is an ancient Mesoamerican technology. Archaeological evidence places early examples in Guatemala’s southern coast around 1200–1500 BCE, and Indigenous civilizations including the Maya and Aztec used alkaline materials such as slaked lime and ash. The word comes from Nahuatl terms associated with lime ash and cooked corn dough.

The process is more than a preparation trick. It softens corn, improves grinding and dough formation, changes flavor, and increases the availability of niacin and tryptophan. That nutritional effect helped protect traditional maize-based diets from pellagra. Nixtamalization is often confused with fermentation, but it is an alkaline treatment rather than a microbial one.