The Masa Movement: Why Nixtamalization Matters

Nixtamalization is a 3,000-year-old technique that transforms dried corn into something fantastic. And for most of the 20th century, Americans forgot it existed.

The word comes from Nahuatl, the Aztec language. Nextli means lime ashes. Tamalli means corn dough. Together they describe a process that Mesoamerican cooks developed between 1200 and 1500 BCE on Guatemala's southern coast. They discovered that cooking corn in an alkaline solution completely changed the grain.

What Nixtamalization Actually Does

The process starts with dried corn kernels soaked and cooked in water mixed with calcium hydroxide, commonly called cal or slaked lime. After steeping overnight, the corn is rinsed and the softened hulls slip off. What remains is nixtamal, ready to be ground into masa.

Alkaline processing dissolves hemicellulose, the glue holding corn's cell walls together. This loosens the hull and softens the kernel. But the changes go deeper than texture.

Raw corn contains niacin, vitamin B3, but most of it is bound to starches in a form called niacytin. The human digestive system cannot absorb it. Nixtamalization breaks these bonds and makes the niacin bioavailable. The process also frees tryptophan, an amino acid that the body converts into additional niacin. About 60 milligrams of dietary tryptophan produces 1 milligram of niacin.

The benefits extend beyond vitamins. Calcium content increases by as much as 750 percent, with most of it available for absorption. The treatment deactivates mycotoxins by up to 97 to 100 percent, including aflatoxins, which are carcinogens produced by mold. Iron, copper, and zinc levels also rise.

And then there is flavor. Fresh nixtamal produces masa with a toasty, mineral-rich aroma that disappears in industrial processing. When a properly made tortilla hits a hot comal, it smells like warm popcorn and wet stone.

The Pellagra Epidemic America Forgot

When corn traveled from the Americas to Europe after Columbus, the nixtamalization process did not travel with it. Spanish explorers watched indigenous cooks prepare corn but apparently did not think the lime treatment mattered. They brought home the grain without the knowledge.

This turned out to be catastrophic.

Populations in Europe and the American South that adopted corn as a dietary staple without nixtamalization began developing a disease called pellagra. The symptoms progress through what doctors call the four Ds – dermatitis, diarrhea, dementia, and death. A distinctive red rash appears on sun-exposed skin, often in a butterfly pattern across the face. Left untreated, the disease destroys the nervous system.

Pellagra first appeared in Spanish peasants in 1735. By the early 20th century, it had become epidemic in the American South. The U.S. Public Health Service reported the first American case in 1902. Within two decades, the disease was striking 250,000 people annually and killing at least 7,000 per year across 15 southern states.

The victims were predominantly poor. Their diets consisted of what researchers called the three Ms – meat (salt pork), meal (cornmeal), and molasses. Between 1907 and 1940, approximately 3 million Americans contracted pellagra and around 100,000 died.

Dr. Joseph Goldberger, a Public Health Service epidemiologist, identified the cause in 1915. He observed that in mental hospitals and orphanages, patients and children developed pellagra while staff did not. The difference was diet. He induced the disease in prison volunteers who ate only corn-based foods and cured it by adding fresh meat, milk, and vegetables.

Medical resistance was fierce. Southern doctors preferred theories about spoiled corn or insect transmission to Goldberger's uncomfortable conclusion that poverty and malnutrition were killing their patients. Goldberger died of kidney cancer in 1929, still searching for the specific missing nutrient. Eight years later, biochemist Conrad Elvehjem at the University of Wisconsin finally isolated niacin as the pellagra-preventing factor.

Here is the bitter irony. Indigenous communities in Mexico and the American Southwest who ate nixtamalized corn never suffered from pellagra. They had solved the problem thousands of years earlier. Mesoamerican cooks paired their tortillas with beans, which provided tryptophan and completed the amino acid profile. The combination produced adequate niacin through multiple pathways.

The knowledge existed, but it did not cross the Atlantic.

How Industrial Masa Changed Everything

In 1949, a teenager named Roberto González Barrera convinced his father to buy a small corn mill in Cerralvo, Mexico. González Barrera was just 18 when he first encountered corn milling the year before and recognized its potential. He and his father founded a company that would eventually become Gruma, the world's largest producer of corn flour and tortillas.

The company's innovation was masa harina, dehydrated nixtamalized corn flour sold under the brand name Maseca. The name combines masa (dough) and seca (dry). Mix it with water and you get workable dough in minutes, no overnight soaking required.

Mexican consumers initially rejected it. The flavor was bland, the texture grainy. Rumors circulated that Maseca cut its flour with paper pulp. Sales limped along for decades.

Then González Barrera's political connections paid off. When Carlos Salinas de Gortari became president of Mexico in 1988, he changed the rules of the tortilla market. In 1990, the government froze corn subsidies to traditional tortilla makers and required that all market growth come from masa harina. The only masa harina producers were Gruma and the Mexican government.

Tortillerias that refused to switch received inferior corn and restricted supplies. Hundreds went out of business. By the mid-1990s, Maseca controlled three-quarters of Mexico's corn flour market.

The industrialization had consequences beyond flavor. Traditional tortilla makers bought corn from local farmers growing landrace varieties, the 59 native races that CONABIO, Mexico's national biodiversity commission, has documented. These corns have names like Olotillo, Cacahuacintle, and Cónico. They come in white, yellow, blue, red, and purple. Each produces masa with distinct characteristics.

Industrial flour uses commodity corn, typically a single variety optimized for yield rather than flavor. The high-temperature drying process that creates shelf-stable masa harina also drives off volatile compounds responsible for the grain's complex aroma. What remains is convenient but comparatively one-dimensional.

The Revival

Something shifted around 2015. Chefs in American cities started nixtamalizing corn in their restaurant kitchens. They were seeking the flavors they remembered from Mexico or from their grandmothers' kitchens.

Dallas chef Anastacia Quiñones had been making tortillas from fresh masa at her restaurant Alma since 2011. Similar programs appeared in Los Angeles, Chicago, and New York. Rick Bayless opened Frontera Grill in Chicago partly because the city had tortilla makers working with fresh masa.

The limiting factor was corn. American chefs could nixtamalize, but they struggled to source the heirloom varieties that make the best tortillas.

Jorge Gaviria saw the gap. Growing up in Miami surrounded by Latin American food traditions, he consumed masa constantly but understood little about it. After training at restaurants including Blue Hill at Stone Barns, he started researching the ingredient. In 2014, he founded Masienda, a company that connects smallholder farmers in Mexico with chefs and home cooks in the United States.

Masienda now works with a network of 2,000 small-scale growers who cultivate heirloom varieties using traditional methods. The company supplies restaurants like Pujol, Cosme, and dozens of others. It also sells directly to home cooks, offering whole kernel corn for nixtamalizing, cal for the alkaline bath, and stone-ground masa harina made from single-origin heirloom corn.

Gaviria calls this Third Wave Masa, borrowing language from the specialty coffee movement. The goal is active consumption rather than passive consumption. Cooks who choose this approach know where their corn comes from and how it was processed. They select ingredients based on flavor and nutrition rather than convenience alone.

His 2022 cookbook, Masa: Techniques, Recipes, and Reflections on a Timeless Staple, was a James Beard nominee and made best cookbook lists from the Los Angeles Times, Food & Wine, and NPR. It covers both the history and the practical techniques for making masa at home.

Small molinos have opened in cities across the country. For All Things Good in Brooklyn nixtamalizes heirloom corn and grinds it daily with volcanic stones. Similar operations exist in Los Angeles, Austin, and Portland. They sell fresh masa by the pound and make tortillas that taste nothing like the packages in supermarket refrigerator cases.

Trying It Yourself

You do not need a volcanic stone mill to experience the difference. High-quality masa harina made from heirloom corn produces tortillas far superior to mass-market alternatives. The ingredient list should be short – corn and lime.

For the full experience, start with whole kernel corn. Masienda and Tamoa sell heirloom varieties ready for nixtamalizing. The process requires only a large pot, cal, water, and time. Soak and cook the corn one evening. Rinse and grind the next morning. Try a traditional hand mill, but keep in mind it is a slow process. The masa should feel like Play-Doh, smooth and pliable.

Press the dough thin. Cook on a dry comal or cast iron skillet over medium-high heat. Flip twice. A properly made tortilla puffs with steam and separates into two layers.

Mexico has more than 600 dishes based on nixtamalized corn. Tortillas are only the beginning. There are tamales wrapped in corn husks or banana leaves. Sopes with thick edges to hold toppings and tetelas folded into triangles. Tlacoyos stuffed with beans and pozole, the famous stew served for celebrations.

All of them start with the same 3,000-year-old technique. This process has sustained civilizations for millennia. It will also sustain the home cooks – like you – who take the time to learn it.