sign for Maseca brand corn flour on the corrugated siding of a building by a white window

Maseca Flours Test Positive for Weedkiller and GMOs. What Should Consumers Do?

October 18, 2018 | Mariana Ortega

Organic Consumers Association

Editor’s note: Read this article in Spanish here.

Are those tortillas you’ve been making with Maseca flour toxic?

On October 9, the Organic Consumers Association reported that samples of Maseca white and yellow corn flour tested positive for concerning levels of glyphosate, the active ingredient in Monsanto’s Roundup weedkiller.

Testing also revealed that some Maseca flour samples tested as high as 94.15 percent for the presence of genetically modified organisms (GMO). That’s a startling finding, given that GMO crops are not allowed to be grown commercially in Mexico.

Those findings can mean only one thing—Mexico-based Gruma, which owns the Maseca brand, is importing GMO corn from the U.S. to produce its flour, sold all over the world, including in Mexico and the U.S.

Since we revealed our test results, concerned consumers from the U.S., Mexico and Canada have reached out asking what they should do. So we’ve researched some alternative corn flour brands that aren’t contaminated with glyphosate and aren’t made from GMO corn.

Maseca flour, masa and traditional Mexican cuisine

Many consumers use Maseca flour to make tortillas, tacos, tamales and many other Mexican dishes, by mixing the flour with water to make corn masa, a paste or dough. But traditionally, corn masa wasn’t made from flour. It was made using a process called nixtamalization, invented in Mexico more than 1,000 years ago, that turned corn into masa without ever using corn flour.

Nixtamalization follows four general steps: cooking corn in an alkaline solution, letting it rest overnight, draining it and grinding it to produce the masa. It’s a time consuming process, but it also creates a much more nutritious product than if the maize weren´t cooked in alkali. Nixtamalization makes the vitamins in the corn more bioavailable. It also fortifies the corn’s calcium and helps it maintain its fiber content. This is why traditional tortillas are a highly nutritious staple food for Mexicans.

The nixtamalization process stayed true to its origins until the 1950s, when industrialization took over. According to a study by Pilcher (1998):

Agricultural and industrial modernization served not to replace the tortilla but, rather, to commodify it, transforming corn from a subsistence crop to a market commodity.

The brand Maseca, meaning masa seca or dried masa, was launched in 1949. It is now the world’s leading brand of commercial masa flour and tortillas. The debut of Maseca coincided with the Green Revolution, increasing use of agrochemicals, hybrid seeds and “improved” productivity. It is not surprising that residues in Maseca’s flours have been found.

Alternative organic, non-GMO tortilla and flour brands

Eating is a political act. Boycotting Maseca’s products is one way to vote against companies whose production practices harm human health and the ecosystem.

Fortunately, there are many available alternatives to risky and suspicious masa flours and tortillas. As part of the “Yo quiero mi tortilla 100% nixtamalizada” (I want my tortilla 100% nixtamalized) campaign, OCA Mexico is mapping consumer sources for tortillas, masa and native corn. This is a collaborative, continuously updated map. Consumers can send a pinpoint location to OCA whenever they identify a place that sells good quality tortillas. Check out the map and fill in your recommended tortilla or masa brand or store.

Our map features a couple of farmer’s markets in the U.S., several tortillerías in Mexico and some sources in Europe. Here’s a list of places you can buy organic tortillas and tortilla chips:

• Three Sisters Nixtamal, in Portland, Oregon, sells regionally. This company has produced a series of very nice short videos on the nixtamalization process.

• Ricardo’s Tortilla Factory, in Canton, Massachusetts, sells nationally.

• Mi Tierra Tortillas, in Springfield, Massachusetts, sells regionally.

• Mitla Tortilleria, in Charleston, South Carolina, sells regionally.

• Bueno Foods, in Albuquerque, New Mexico, sells nationally.

• Cadia, sells tortilla chips.

• All Souls Tortilleria, in Warren, Vermont,, sells regionally.

• La Tortilla factory, in Santa Rosa, California, sells nationally.

• Mi Rancho, from San Leandro, California, sells nationally.

• R.W. Garcia Tortilla chips, in Scotts Valley, California, sells nationally.

• One Degree Organic Foods

• Que Pasa Foods, in Richmond, British Columbia, is available in Canada

• 365 Everyday Value/WholeFoodsMarket, sells nationally.

• Masienda, also found at Whole Foods Market nationally.

Whole Grain Milling, in Welcome, Minnesota, sells regionally

You can also buy organic corn flours and corn grain from this producers and retailers:

• Gold Mine Natural Foods  

• Organic Matters foods

• To Your Health. Sprouted Flour Co

• Grain Millers

• Golden Organics

• Paul’s Grains

• Gluten Free Essentials

• Something Better Natural Foods

• Earth’s Harvest Farms

Whole Grain Milling

You can also check out the following directories on organic and natural foods retailers, food cooperatives and healthy food grocery stores organized by state:

• Green People Directory from OCA

• Independent Natural Food Retailers Association

• Cooperative Grocer Network

• Co-Op Directory Service Listing

• Co-Op Stronger Together

Also interesting, you can listen to the radio station YoSoyMaíz in Los Angeles and stay tuned to follow up on the news concerning corn and tortilla.

In Mexico, you can get nixtamalized tortillas made from native corns here:

• Vía Orgánica, San Miguel de Allende, Guanajuato

• Ichuskuta Tortilla Artesanal, Morelia, Michoacán

• Las Tortillas de Mi Abuelita, Iguala de la Independencia, Guerrero

• Tortillas Pipitillas, Cuernavaca, Morelos

• Cal&Maíz, Mexico City

• Cintli Tortillería y Antojería, Mexico City

• L’Artesana Tortillas, Mexico City

• Maizajo Molino y Tortillería, Mexico city

• Molino y Tortillería El Pujol, Mexico City

• Tortillería Corazón de Milpa, Cholula, Puebla

• Matí Tlaolle, Tenancingo, Tlaxcala

• Itanoní Restaurant, Oaxaca de Juárez, Oaxaca

• El Rayito de Sol, Mérida, Yucatán

• Pro-Orgánico, a tortilla brand available in some supermarkets. You can read their story here. It gives a fair understanding of the maize-tortilla system in Mexico.

These are examples, but not a complete list. Here is a directory with places where you can find healthy food in Mexico—most do sell tortillas.

Do-it-yourself masa and nixtamalization

Most tortillerías have a mill where you can take your own nixtamalized native corn to be ground, and make your own masa from scratch. If you’re preparing a small quantity, you can even grind it yourself in a small manual grinder or a food processor.

Find a local corn farmer or a reliable seller and try nixtamalization. In Mexico, you can look into TAMOA, an organization building a native corn farmer´s network and commercializing their produce. In the U.S., you could contact a farm or retailer from the listings mentioned above.

Nixtamalization is a fairly simple process. Begin by boiling water. For each kg of corn (2.2 pounds) you plan to add to the water, you’ll need 2L (34 oz.) of water. Next, add 10g (0.36 oz.) of food-grade lime. Once the water-lime solution is boiling, add the corn and leave the heat on for 5 more minutes. Then, turn it off and cover the pot it with a lid. Preferably, use stainless steel utensils.

Leave the corn in the alkaline solution to rest for 8 hours until it has cooled down. Then drain the liquid, which is called nejayote. Now you’re ready to make the masa. Begin by rinsing the nixtamal with clean water (optional, but recommended).

Next, grind the nixtamal until the texture resembles a paste or dough. You can use either a manual nixtamal grinder (which you will most probably have to buy in Mexico) or a metate (the original Mesoamerican grinder, also available in Mexico). Food processors could work as well, but only for small quantities.

That’s it! Now you’re ready to turn the masa into one of many Mexican dishes: tortillas, sopes, tamales or atole. You can mix masa with any vegetable and give it different flavors and colors.

Best of all, as long as you start with organic ingredients, you’ll know exactly what you’re eating—masa with no chemical additives!

Join the movement for healthy masa and tortillas

Follow OCA and take part in its Yo quiero mi tortilla 100% nixtamalizada campaign. Let us know about reliable masa and tortilla brands and where to buy them so we can pin the locations to the collaborative map.

Help us raise the voice by supporting political campaigns and lobbying work. Become a member of the Alianza por Nuestra Tortilla, a Mexico initiative working for  traditional high quality tortilla for all.

Mariana Ortega is campaign director for Organic Consumers Association Mexico (ACO), a project of US-based Organic Consumers Association (OCA). OCA is a US-based 501(c)(3) nonprofit consumer advocacy organization focused on food, agriculture and environmental issues.To keep up with OCA news and alerts, sign up for our newsletter.