This Ancient Secret for Making Tacos Nutritious and Safe Is Still Used Today

A woman prepares Mexican street food: mole enchiladas, fried tamales, fried tacos and quesadillas. Jacobo Zanella/Getty Images

The last time you saw #TacoTuesday trending on social media, you probably didn't give a second thought to nixtamalization. And yet it's an important process we can thank ancient civilizations for, because it increases the enjoyment — and safety — of tacos. What the heck is nixtamalization anyway?

The word comes from the Aztec language called Nahuatl and is a product of two words meaning "ashes" and "unformed corn dough" or tamal. This culinary technique is a centuries-old way of processing corn, perfected by pre-Columbian civilizations.


But there's way more to it than that. Native American societies — the Aztecs, Mayans and Incans, for instance — knew that nixtamalization helped get the corn ready for making a soft dough. It also was necessary to make the corn safe for their diet.

They did this by soaking the dried kernels in an alkaline mixture of water, ash and lime. Steeping the kernels this way made the corn easier to digest and more nutritious.

So what does all of this have to do with #TacoTuesday? We still use basically the same process today that they did. It's important in making masa, the dough used for tamales, tortillas and taco shells. Soaking the corn in the alkaline mixture breaks down the cell walls of the kernels, making the corn easier to grind into flour.

How and why the pre-Columbian people developed the technique of nixtamalization is a mystery. But the 18th-century Europeans learned the hard way that you don't want to skip this step.

When corn became a large part of the diet of many Europeans, they enjoyed it without nixtamalization. The process seemed unnecessary to them. But what resulted was a rampant outbreak of pallegra, which is a terrible disease caused by niacin deficiency. (Symptoms include sensitivity to sunlight, skin lesions, dementia and death if not treated.) Today we know that nixtamalization releases the niacin in the corn, making it easier to absorb, as well as reduces toxins produced by fungi called mycotoxins.

Nixtamalization not only helps make killer tacos, but it also helps make them a little bit safer for us to eat.