Cover Image by Carl Nebel – Voyage pittoresque et archéologique dans la partie la plus intéressante du Mexique par C. Nebel, Architecte. 50 Planches Lithographiées avec texte explicatif., Public Domain


  • the left over water after nixtamalization.
  • Agua amarillenta en que se ha cocido el maíz. The “yellow water” in which corn has been cooked (nixtamalized)

Also nijayote : from Guerrero Nahuatl nexayotl, Tlamacazapa Nahuatl nexayotl

Corn was traditionally processed by cooking and steeping the kernels with lime or wood ashes (1), discarding the cooking liquor or nejayotl (from tenextli = lime and ayotl = broth)(2), and rubbing the resulting soft nixtamalli between the hands to remove the bran. The washed product, nixtamal, was hand ground with a cylindrical stone and a metatl or flat stone slab.

  1. See Post : Nixtamal for further information on the process, its history and the various reasons it is done this way.
  2. although according to the Nahuatl dictionary ayotl means : anything having to do with water; juice, juice of marinated or crushed herbs; brine, juice of crushed meat; broth. It can also mean soup; stew (or even “large turtle/tortoise”)

Images from various codices

Nixtamal is from the Nahuatl nixtamalli or nextamalli which is from the root word nextli (ashes). One way to make this alkaline soaking/cooking liquid (nejayote) is to use hardwood ash (which is high in potassium hydroxide). More commonly these days it is done with calcium hydroxide or “cal” as it is known.

The Aztecs knew this.

Cal or “slaked lime” is made by processing limestone or seashells in a particular way. An alternate root for the word nixtamal is “tenextli” which means (quick)lime in Nahuatl. Tenextli is a compound of te- (from tetl – stone) and nextli (ashes/cinders), which fairly clearly points to burned stone, in this case limestone, called cal in Spanish.

  1. This compound glyph for the place name Nextitlan consists of two principal visual elements, a cloud of ashes [nex(tli)] with a mouth of white teeth [tlan(tli)] in the middle. The ashes are dotted and washed over with a dark gray. The teeth are both top and bottom front teeth, very white, and the mouth is slightly open. An oval black line unites the top and bottom teeth. The teeth are there to provide the phonetic locative suffix (-tlan = “place of” or “place near an abundance of”)
  2. This glyph for nex(tli) (cinder, ash) has been carved from the compound sign for the place name, Nextitlan. We have removed the teeth that were imbedded in the middle of the compound glyph, providing the locative “tlan.” This glyph may be showing more than ashes or cinder, but may be referring to a type of black volcanic soil that contains small stones.

There is evidence that “lime-cooking” was already in use by 100BC in Teotihuacan (Rooney etal 2016). It is noted in the Medocino Codex that villages in nearby Puebla supplied (amongst other items) 4,000 loads of limestone as tribute. He also noted that Mayans, after eating fresh water mussels, burned the shells into ashes which were then used as an alkalising agent.

In Mexico, the tortilla industry generates millions of cubic meters of nejayote annually and there is no standardized strategy for managing this by-product, especially since 50% of this effluent is produced in small local tortilla factories.

Vats of nixtamalizing maiz

In Mexico there are currently over 100,000 small and 25 large masa manufacturing facilities which consume over 2.2 billion gallons of water. About 83 percent (1.8 billion gallons) of water consumed for masa production is disposed of as wastewater or nejayote. Up until recently, industrial nejayote has been dumped into water bodies (rivers or lakes), in soils or in the public sewer system, and rarely was previously treated (Salmerón-Alcocer et al., 2003).

A typical (small) maize nixtamalization facility, processing 500 kg of maize every day, uses over 750 L of water per day (Farooq etal 2017). In Guatemala it has been noted (Cifuentes de Gramajo 2001) that 63% of (household level produced) nejayote is released into water ecosystems without any treatment and 24% is released directly into the environment (i.e. poured directly into roadside drains).

This can have a negative effect on the environment as the chemical and physical characteristics of nejayote make it a highly pollutant effluent if not adequately processed. The high pH (11-13) and high pollutant levels of nejayote is potentially harmful to several environmental ecosystems.

This is also a huge issue concerning water use and conservation. Water conservation is of utmost importance in part because up to 54 percent of the population in Mexico will experience physical water scarcity by the year 2025 (Barker et al., 2000). Gruma, S.A.B. de C.V., known as Gruma, is a Mexican multinational corn flour and tortilla manufacturing company headquartered in San Pedro, near Monterrey, Nuevo León, Mexico. It is the largest corn flour and tortilla manufacturer in the world. Its brand names include Mission Foods, Maseca, and Guerrero. Their nixtamalization processing alone uses up to 6 million cubic meters of water per year. The uncontrollable amount of water needed for the process was causing an impact in the ecosystem that was near the plants that had this nixtamalization process. They needed a more sustainable process that wouldn’t destroy its surroundings. Previously this water couldn’t be purified and reused. Through the use of bacteria and innovative water treatment processes, GRUMA is now able to reuse 90% of the water that nixtamalization requires, thus saving up to 5.5 billion litres of water per year.

Nixtamalization causes a loss of about 5% by weight dry basis of corn (1); 3% is suspended and the remaining 2% is dissolved. (López-Maldonado etal 2017)

  1. other sources state these losses to be as high as 14.5% (Rosenstrater 2006)

Nejayote also contains hydrolyzed parts of the grain such as pericarp tissue, germ, and endosperm, and therefore it is rich in carbohydrates, calcium, phenolic compounds and proteins (albumins, globulins, and prolamins).

One paper (Cifuentes de Gramajo 2001) however did note that “nejayote has a great potential to be reused to minimize any negative impacts and be a resource to its producers. Its high concentrations of about 200 to 300 ppm of nitrogen, 160 to190 ppm of phosphates and 26 500 to 28 000 ppm of COD (1) (Salmerón-Alcocer etal 2003) suggest its potential use as organic fertilizer or soil conditioner that could release some stress from the environment decreasing the utilization of chemical products”.

  1. Chemical oxygen demand, or COD, is the measure of the capacity of water to consume oxygen during the decomposition of organic matter in the water. In other words, it’s the amount of oxygen that’s needed to oxidise the organic matter present in a quantity of water (or a measure of how much oxygen would be depleted from a body of receiving water as a result of bacterial action). COD is a water quality measure used not only to determine the amount of biologically active substances such as bacteria but also biologically inactive organic matter in water. It is an important and rapidly measured variable for characterizing water bodies, sewage, industrial wastes, and treatment plant effluents. When the COD levels are higher, there is a greater demand for oxygen. This means that there is likely more oxidizable organic material in water with high COD levels. This also means that there are reduced Dissolved Oxygen (DO) concentrations in wastewater with high COD levels. The higher the value of COD indicates the higher level of organic pollutants in the water. Dissolved oxygen (DO) is one of the most important indicators of water quality. It is essential for the survival of fish and other aquatic organisms. Too much dissolved oxygen is not healthy, either. Extremely high levels of dissolved oxygen usually result from photosynthesis by a large amount of plants. Great uncontrolled plant growth, especially algal blooms, is often the result of fertilizer runoff. This phenomenon is called cultural eutrophication. (Authors note : perhaps there is some merit in using nejayote to address algal blooms in waterways infested with photosynthesising organisms that produce algal blooms?)

Most past attempts to reduce nejayote effluent have failed because changes in the traditional masa production process also cause changes in final product quality. Masa production processes and the masa product quality have been the same for thousands of years causing resistance to masa production process changes.

Researchers at Tecnológico de Monterrey in collaboration with researchers from other campuses such as Querétaro (Dr. Julián de la Rosa-Millán), Puebla (Dr. María del Refugio Rocha-Pizaña and Sonora (Dr. Patricia I. Torres-Chávez) have researched the potential of this waste liquid as an adjunct treatment (in cancer no less). They state “Currently, we know that nejayote can remove up to 50% of the antioxidants in corn, some of which have been proven to have beneficial properties on health.”

In the study mentioned above the Nejayote was centrifuged, acidified to pH 2 and most of the phenolic compounds were extracted with ethyl acetate. This was then used as a basis for the study. It was found that the conjugated antioxidants recovered from nejayote have increased anti-inflammatory activity and it was noted in the study that “The prevention of cancer and the regulation of processes related to inflammation are among the beneficial effects of the compounds that are released from the corn towards this aqueous effluent of nixtamalization”.

This study has exciting potential

Ferulated arabinoxylans and polyphenols contained in nejayote have drawn the attention of other researchers (Berlanga-Reyes etal 2011). In case of Arabinoxylans, they have generated research interest due to their nutraceutical properties and health benefits such as lowering blood cholesterol and sugar, cardiovascular diseases, chemopreventive activity, quinone reductase activity, and cytotoxic as well as antioxidants properties.

Further study is required.

Other potential uses that have been given to nejayote are aimed at recovering components of high added value (González etal 2003) (Niño-Medina etal 2009) (PazSamaniego etal 2015), as a source of enrichment for functional foods (Acosta-Estrada e al 2014) or as a culture medium for bacterial growth (Blanco-Gámez etal 2008).

Rosentrater (2006) has investigated nejayote as a stockfeed for ruminant animals (cows/goats/sheep)(1) and chickens.

  1. and pronghorns, giraffes, okapis, deer, chevrotains, and antelopes too I guess.

Just in case you were wondering what a freaking chevrotain is (I know I did).

Chevrotain (or mouse deer) are small ruminant mammals. The smallest of the hoofed mammals (standing about a foot high at shoulder), they are characterized by slender legs, delicately built hoofs, a tapered snout, three fully developed stomach chambers (the fourth, the omasum, is poorly developed), and a primarily solitary, herbivorous, nocturnal behaviour; they lack antlers and horns, but males have small, curved, downward protruding, tusk-like upper canine teeth. Chevrotains are found in parts of south-eastern Asia and Africa.

Medicinal use of nejayote


DO NOT DRINK UNPROCESSED NEJAYOTE. It is a highly alkaline liquid that can burn.

DO NOT CONSUME Cal. Take care not to breathe in Cal.

Small amounts of wood ashes may be added to food but the concentrated mix of wood ash and water is highly alkaline and MUST NOT be consumed.

Don’t drink this. Shit don’t even get it on your skin. See WARNINGS below regarding alkali burns.

Alkali burns are caused by lye (1) (e.g., Drano, Liquid Plummer), lime, or ammonia, in addition to other agents; they are characterized by liquefaction necrosis (2). They are worse than acid burns because the damage is ongoing. It takes less than seven drops in an oral dose for it (lye) to be lethal to a 68 kilogram (150 pound) human being. A single taste of lye would cause third-degree burns on the mouth and the oesophagus.

  1. A lye is a metal hydroxide traditionally obtained by leaching wood ashes, or a strong alkali which is highly soluble in water producing caustic basic solutions. “Lye” most commonly refers to sodium hydroxide NaOH, but historically has been used for potassium hydroxide KOH.
  2. Liquefactive necrosis (or colliquative necrosis) is a type of necrosis which results in a transformation of the tissue into a liquid viscous mass. This involves the denaturing of proteins as well as saponification (3) of adipose tissue (4), which does not limit tissue penetration. Alkalis cause deeper burns as they continue to penetrate the skin following initial contact.
  3. Saponification is a process that involves the conversion of fat, oil, or lipid, into soap and alcohol (glycerol)(5) by the action of aqueous alkali. The reaction is called a saponification from the Latin sapo which means soap
  4. Adipose tissue is commonly known as body fat. It is found all over the body. It can be found under the skin (subcutaneous fat), packed around internal organs (visceral fat), between muscles, within bone marrow and in breast tissue. Here we are talking about the fat found under the skin.
  5. Glycerol, also called glycerine in British English and glycerin in American English, is a simple polyol compound. It is a colourless, odourless, viscous liquid that is sweet-tasting and non-toxic. The glycerol backbone is found in lipids known as glycerides

Potassium hydroxide Exposure/Poisoning

Symptoms from swallowing potassium hydroxide include:

  • Burns and severe pain in the mouth and throat
  • Throat swelling, which leads to difficulty breathing
  • Drooling
  • Severe abdominal pain
  • Diarrhoea
  • Chest pain
  • Rapid drop in blood pressure (shock)
  • Vomiting, often bloody

Symptoms from getting potassium hydroxide on the skin or in the eyes include:

  • Burning
  • Severe pain
  • Vision loss

Seek immediate medical help. DO NOT make a person throw up unless told to do so by poison control or a health care professional.

If the chemical is on the skin or in the eyes, flush with lots of water (at least 2 quarts or 1.9 liters) for at least 15 minutes.

If the chemical was swallowed, immediately give the person water or milk, unless instructed otherwise by a health care provider. DO NOT give water or milk if the person is having symptoms (such as vomiting, convulsions, or a decreased level of alertness) that make it hard to swallow.

If the person breathed in the powder, immediately move them to fresh air.

For skin exposure, treatment may include:

  • Surgical removal of burned skin (debridement)
  • Transfer to a hospital that specializes in burn care
  • Washing of the skin (irrigation), possibly every few hours for several days

The person may need to be admitted to a hospital for more treatment. Surgery may be needed if the esophagus, stomach, or intestines have holes (perforations) from the chemical burns.

Calcium hydroxide (Cal) Exposure/Poisoning

Calcium hydroxide has several forms and names, including:

  • calcium dihydroxide
  • calcium hydrate
  • calcium(II) hydroxide
  • food-grade lime
  • hydrated lime
  • lime
  • pickling lime
  • slack lime
  • slaked lime

Food-grade lime is the form of calcium hydroxide used in food.

Food-grade calcium hydroxide is generally safe. However, if you work with industrial-grade calcium hydroxide, ingesting it can result in calcium hydroxide poisoning. This can lead to severe injury or death.

Some signs and symptoms of calcium hydroxide poisoning include:

  • vision loss
  • severe pain or swelling in your throat
  • a burning sensation on your lips or tongue
  • a burning sensation in your nose, eyes, or ears
  • difficulty breathing
  • abdominal pain, nausea, and vomiting
  • vomiting blood
  • blood in the stool
  • loss of consciousness
  • low blood pressure
  • low blood acidity
  • skin irritation

Swallowing industry-grade calcium hydroxide is a medical emergency that requires immediate treatment. If you suspect you’ve ingested industry-grade calcium hydroxide, call your local Poison Control Centre for advice.

Get medical help right away. DO NOT make the person throw up unless poison control or a health care provider tells you to.

If the chemical is on the skin or in the eyes, flush with lots of water for at least 15 minutes.

Among the few chemical toxins that should NOT be irrigated immediately with water are dry lime, phenols, and elemental metals (eg, sodium, potassium, calcium oxide, magnesium, phosphorous). Dry lime should be brushed off the skin prior to irrigation. It contains calcium oxide, which reacts with water to form calcium hydroxide, a strong alkali. Elemental metals and certain reactive metal compounds combust or release hazardous byproducts when exposed to water. Examples include: sodium, potassium, magnesium, phosphorous, lithium, cesium, and titanium tetrachloride.

If the chemical was swallowed, immediately give the person water or milk, unless instructed otherwise by a provider. DO NOT give water or milk if the person is having symptoms (such as vomiting, convulsions, or a decreased level of alertness) that make it hard to swallow.

If swallowed treatment may include:

  • Fluids through a vein (by IV)
  • Tube through the mouth into the stomach to wash out the stomach (gastric lavage)
  • Washing of the skin (irrigation), every few hours or for several days
  • Surgery to remove burned skin
  • Breathing support, including tube through the mouth into the lungs and connected to a breathing machine (ventilator)

Traditional Medicinal Use.

In traditional Mixtec medicinal practices an illness called Mocazani (or Cachani) can occur in women after childbirth.

Disease of the puerperal (1) woman, produced “because she has an intimate relationship with her husband when she has just given birth”. The period during which the condition can arise is 40 days after childbirth, a stage considered to be very careful, since the woman is still “open” and can easily get sick (V. quarantine ). The mocazani manifests itself with fever, lack of appetite and decay; the patient looks sad, she feels bad, her hair falls out and she has a rash, that is, vaginal discharge; sometimes her whole body swells up and she gets diarrhoea. The treatment should be started as soon as the woman presents the first symptoms, since otherwise “every day that passes, it gets worse” and she could die. She cures herself “with nixtamal nejayotl , clear, boiled with a piece of tlacuache (2) tail “. It is reported that the tail of this animal “cleans the womb, removes inflammation and helps to close the hip.” The preparation is given to drink once a day for three days. For some time it is recommended not to eat pork or spicy foods; Likewise, the patient must take care of herself, not overwork or lift heavy things

  1. during or relating to the period of about six weeks after childbirth during which the mother’s reproductive organs return to their original non-pregnant condition.
  2. Opossums : members of the marsupial order Didelphimorphia endemic to the Americas. Prehispanic Mesoamerican medicine also makes use of skunk meat for its healing qualities. See Post : Skunkweed and the Skunk for more information on this.


  • Acosta-Estrada, B. A., Lazo-Vélez, M. A., Nava-Valdez, Y., Gutiérrez-Uribe, J. A., & Serna385 Saldívar, S. O. (2014). Improvement of dietary fiber, ferulic acid and calcium contents in pan 386 bread enriched with nejayote food additive from white maize (Zea mays). Journal of Cereal 387 Science, 60(1), 264-269.
  • Acosta-Estrada, B. A., Serna-Saldívar, S. O., & Gutiérrez-Uribe, J. A. (2015). Chemopreventive 390 effects of feruloyl putrescines from wastewater (Nejayote) of lime-cooked white maize (Zea 391 mays). Journal of Cereal Science, 64, 23-28.
  • Argun, Mustafa & Argun, Mehmet. (2017). Treatment and alternative usage possibilities of a special wastewater: Nejayote. Journal of Food Process Engineering. 41. 10.1111/jfpe.12609.
  • Ayala-Soto, F. E., Serna-Saldívar, S. O., García-Lara, S., & Pérez-Carrillo, E. (2014). 394 Hydroxycinnamic acids, sugar composition and antioxidant capacity of arabinoxylans extracted 395 from different maize fiber sources. Food Hydrocolloids, 35, 471-475. 396
  • Berlanga-Reyes, C., Carvajal-Millan, E., Niño-Medina, G., Rascón-Chu, A., Ramírez-Wong, B., Magaña-Barajas, E.: Low-value maize and wheat by-products as a source of ferulated arabinoxylans. García Einschlag, F.S. (eds.) Waste Water – Treatment and Reutilization, InTech, Rijeka (2011)
  • Blanco-Gámez, E. A., Sánchez-González, E. A., Valladares, M. N., & Olvera, C. (2008). Identificación de microorganismos aislados del nejayote. Revista salud pública y nutrición, 13, 1-5.
  • Buitimea-Cantúa, Nydia & Antunes-Ricardo, Marilena & Gutiérrez-Uribe, Janet & Rocha, María & De la Rosa-Millán, Julian & Torres – Chavez, Patricia Isabel. (2020). Protein-phenolic aggregates with anti-inflammatory activity recovered from maize nixtamalization wastewaters (nejayote). LWT. 134. 109881. 10.1016/j.lwt.2020.109881.
  • Castro-Muñoz, R., Cerón-Montes, G. I., Barragán-Huerta, B. E., & Yáñez-Fernández, J. (2015). 425 Recovery of carbohydrates from nixtamalization wastewaters (Nejayote) by 426 ultrafiltration. Revista Mexicana de Ingeniería Química, 14(3), 735-744. Retrieved from 427
  • Castro-Muñoz, Roberto; Fíla, Vlastimil; Durán-Páramo, Enrique (2017). A Review of the Primary By-product (Nejayote) of the Nixtamalization During Maize Processing: Potential Reuses. Waste and Biomass Valorization, (), –. doi:10.1007/s12649-017-0029-4
  • Cifuentes de Gramajo, Luisa. (2011) Nejayote produced at household level by Mayan women in Guatemala “Is it a threat to aquatic ecosystems or a resource for food security?”. Kristianstad University SE-291 88 Kristianstad Sweden : MASTER THESIS Spring 2011 Sustainable Water Management
  • Díaz-Montes, Elsa & Castro-Muñoz, Roberto & Yañez-Fernández, Jorge. (2016). An overview of nejayote, a nixtamalization by product. Ingeniería Agrícola y Biosistemas. 8. 41-60. 10.5154/r.inagbi.2016.03.002.
  • Farooq, Robina; Ahmad, Zaki (2017). Physico-Chemical Wastewater Treatment and Resource Recovery || Integral use of Nejayote: Characterization, New Strategies for Physicochemical Treatment and Recovery of Valuable By-Products. , 10.5772/67803(Chapter 11), –. doi:10.5772/66223
  • González, R., Reguera, E., Figueroa, J. M., & Martínez, J. L. (2003). Study of the Influence of nejayote and other additives on the cohesive strength and electric properties of black agglomerates. Journal of Applied Polymer Science, 90(14), 3965-3972. doi: 10.1002/ app.13098
  • López-Maldonado, E. A. , Oropeza- Guzmán, M. T. , & Suárez-Meraz, K. A. (2017). Integral use of Nejayote: Characterization, New Strategies for Physicochemical Treatment and Recovery of Valuable By-Products. In R. Farooq, & Z. Ahmad (Eds.), Physico-Chemical Wastewater Treatment and Resource Recovery. IntechOpen. https://doi.or
  • Niño-Medina, G., Carvajal-Millán, E., Lizardi, J., Rascon-Chu, A., Márquez-Escalante, J. A., Gardea, A., MartínezLópez, A. L., & Guerrero, V. (2009). Maize processing waste water arabinoxylans: Gelling capability and cross-linking content. Food Chemistry, 115(4), 1286- 1290. doi: 10.1016/j.foodchem.2009.01.046
  • Palacios-Pola, G., Perales, H., Estrada Lugo, E.I.J. et al. Nixtamal techniques for different maize races prepared as tortillas and tostadas by women of Chiapas, Mexico. J. Ethn. Food 9, 2 (2022).
  • Paredes, L. O, Guevara, L. F., Bello, P. L. A. (2008). La nixtamalización y el valor nutritivo del maíz. Ciencias, 92-93, 60-70
  • Paz-Samaniego, R., Carvajal-Millan, E., Brown-Bojorquez, F., Rascón-Chu, A., López-Franco, Y. L., Sotelo-Cruz, N., & Lizardi-Mendoza, J. (2015). Gelation of arabinoxylans from maize wastewater-effect of alkaline hydrolysis conditions on the gel rheology and microstructure.
  • Robles Ramírez, María del Carmen & Flores-Morales, A. & Mora-Escobedo, Rosalva. (2012). Corn tortillas: Physicochemical, structural and functional changes. Maize: Cultivation, Uses and Health Benefits. 89-111.
  • Rooney, L.W. & Serna-Saldivar, Sergio. (2016). Tortillas: Wheat Flour and Corn Products.
  • Rosentrater, K A. “A review of corn masa processing residues: generation, properties, and potential utilization.” Waste management (New York, N.Y.) vol. 26,3 (2006): 284-92. doi:10.1016/j.wasman.2005.03.010
  • Salmerón-Alcocer, A., Rodríguez-Mendoza, N., PinedaSantiago, V., Cristiani-Urbina, E., Juárez-Ramírez, C., Ruiz-Ordaz, N., & Galíndez-Mayer, J. (2003). Aerobic treatment of maize-processing wastewater (nejayote) in a single-stream multi-stage bioreactor. Journal of Environmental Engineering and Science, 2(5), 401-406. doi: 10.1139/S03-046


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s