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Revista mexicana de ciencias agrícolas

versión impresa ISSN 2007-0934

Rev. Mex. Cienc. Agríc vol.8 spe 18 Texcoco ago./sep. 2017 


Agrobiodiversity, gender and food sovereignty in Tlaxiaco, Oaxaca

Tomás Ortega Ortega1 

Verónica Vázquez García1  § 

Diego Flores Sánchez1 

Juan Felipe  Núñez Espinoza1 

1Colegio de Postgraduados-Campus Montecillo. Carretera México-Texcoco km. 36.5. Montecillo, Texcoco, Estado de México. CP. 56230. Tel. 01 (595) 9520200, ext. 1888. (;;


Maize has been the staple food of Mesoamerican peoples for millennia. Mexico hosts 59 races and a large variety of dishes that include this grain. Historically, women have been responsible for the preparation of these dishes, with the tortilla as the basis for many of them. This paper analyzes the maize management practices conducted by the women who belong to the Union de Palmeadoras de Tlaxiaco, Oaxaca. Data were obtained in 2015 and 2016 through a methodological strategy that involved interviews, workshops, participant observation, field diaries and a census. The paper describes women’s maize supply networks; nixtamalization -related knowledge; and tortilla selling practices. Results show that palmeadoras activate the market of regional maize varieties, and that they have specialized knowledge on maize transformation into food. It is concluded that women’s skills and needs must be taken into account in public policy design in order to promote gender equality and food sovereignty in Mexico.

Keywords: biodiversity; traditional knowledge; native maize; tortillas


El maíz ha sido la base de la alimentación de los pueblos mesoamericanos por milenios. En México existen 59 razas y una gran variedad de platillos que incluyen al grano. Históricamente las mujeres han sido las responsables de su preparación, siendo la tortilla la base de muchos de ellos. Este artículo analizó el manejo de maíz por parte de las mujeres que integran la Unión de Palmeadoras de Tlaxiaco, Oaxaca. Los datos se obtuvieron en 2015 y 2016 a través de una estrategia metodológica que involucró entrevistas, talleres, observación participante, diarios de campo y un censo. Se describen las redes de abastecimiento de maíz de las mujeres, sus conocimientos relacionados con la nixtamalización y sus prácticas de comercialización de tortillas. Los resultados muestran que las palmeadoras promueven el comercio de maíces de la región y poseen conocimientos especializados sobre su transformación en alimento. Las habilidades y necesidades de las mujeres deben ser tomadas en cuenta en el diseño de políticas públicas encaminadas a promover la equidad de género y la soberanía alimentaria de México.

Palabras clave: biodiversidad; conocimiento tradicional; maíz criollo; tortillas


Mexico is the center of origin and genetic diversity of maize, housing 59 of the 219 races identified in Latin America (Goodman and Bird, 1977; Kato et al., 2013). However, the signing of the North American Free Trade Agreement put this legacy at risk. Imports of basic foods (maize and beans) increased around 43% between 1993 and 2012 (CVASF, 2014). Currently, 12 of the 35 million tons of maize required by the country are purchased every year (Pérez, 2016). The traditional diet has changed (Lerner and Appendini, 2011; Moreno-Flores et al., 2014) and diabetes is one of the leading causes of death in Mexico (SSA, 2007; De Schutter, 2012).

Despite this adverse context, 3.2 million peasant families continue to plant their own maize varieties, thereby promoting the diversity of native maize and food sovereignty (Polanco and Puente, 2013). Peasant knowledge encompasses all the production chain, from the plot to the kitchen: seed selection (Vázquez, 2002), plant management (Chambers and Momsen, 2007), harvest administration (Preibisch et al., 2002), and maize nixtamalization (Hellin et al., 2010; Appendini and Quijada, 2016). However, most studies have focused on maize management in cultivation areas. Post-harvest processing is considered a natural extension of women’s domestic tasks, neglecting the fact that specialized knowledge is required in order to transform the grain into food (Oakley and Momsen, 2007; Appendini and Quijada, 2016).

This paper analyzes the maize post-harvest management practices conducted by the Mixteca women who make up the Unión de Palmeadoras of Tlaxiaco (UPT), Oaxaca. Its members are engaged in the daily elaboration and sale of handmade tortillas. The UPT was created in the 1990s in order to standardize the cost of milling, tortilla size, sale sites and product presentation. The paper describes women’s maize supply networks, nixtamalization-related knowledge and tortilla selling activities in the streets and markets of Tlaxiaco.

Materials and methods

The main concepts of this paper are agrobiodiversity, gender and food sovereignty. The first one analyzes the properties of domesticated species in their environment (Momsen, 2007; Hellin et al., 2010). Gender is a social construction that assigns different responsibilities to men and women in resource management, thus determining their access to them (Lambrou and Laub, 2006). Finally, food sovereignty seeks people’s ability to produce and consume culturally, environmentally and economically sound foods. This concept differs from that of food security in that food has to be produced locally rather than imported. Small-scale farmers must supply domestic markets and receive adequate remuneration for their work. Women play a key role in this productive system (Rocheleau, 1995; Schmitter-Soto et al., 2016).

The paper analyzes two types of maize: native and hybrid. The first refers to maize originated in a community, region, state or country. It is characterized by its heterogeneity. Peasant families distinguish native maize varieties by their color, texture, grain shape, cob shape, precocity and use. These maize varieties have been created in specific agroecological conditions through empirical selection (Aragón et al., 2005; Camacho et al., 2005). In turn, hybrid maize is produced in research centers by crossing genetically different maize types in order to increase harvests and srenghten pest and disease resistance (MacRobert et al., 2015).

Research was conducted in the municipality of Tlaxiaco located in the Oaxaca mixteca. Tlaxiaco has a population of 38 453 people (53% women and 47% men), with mixteco being the most important indigenous language (INEGI, 2010). Eighty-eight per cent of the localities belonging to the municipality report a high marginalization index (CDI, 2010). The UPT has 89 members (88 women and one man) scattered in 14 communities. Only 32 palmeadoras speak Mixteco, although the vast majority of them (85) consider themselves Mixtecas. More than half (47) live with a partner. A similar amount (45) are the main providers of their homes.

Fieldwork began with 36 interviews on the history of the UPT, the palmeadora trade, types and origin of maize, and problems related to the preparation and sale of tortillas. This information was organized to be discussed later with the palmeadoras themselves in five workshops. Finally, a census of the UPT was conducted in order to obtain descriptive statistics for the whole organization. During a period of one year and seven months, participant observation was carried out in commercialization sites, mills, houses where tortillas are made, UPT meeting places and community celebrations. Qualitative data were analyzed with Atlas Ti and quantitative data with Excel.

Results and discussion

Maize supply networks

The maize used to make tortillas includes native (white, blue, yellow and red or reddish) and hybrid (white) varieties. The native ones are produced locally through the milpa system in different communities of the municipality and other villages of the Oaxaca mixteca (Lazos, 2012). The most common breeds in the region are Mixteco, Chalqueño and Cónico (Chávez and Diego, 2011). On the other hand, hybrid varieties are produced outside the municipality, in the states of Sinaloa, Puebla, Guanajuato and Chiapas, through a production system based on monoculture and intensive use of agrochemicals. The grain is commercialized by companies that concentrate markets and distribution channels.

Palmeadoras prefer the native varieties that are usually obtained with local producers. These varieties can also be bought to regional distributors or cultivated in the own plot (Table 1). The same woman can resort to more than one source to make tortillas, depending on the time of the year. By doing so, palmeadoras actively participate in the exchange of different native varieties, a practice that contributes to the conservation of maize.

Table 1 Origin of native maize. 

Origen Número de palmeadoras
Propio de la parcela 28 de 87
Distribuidores 35 de 87
Campesino 62 de 87

Fuente: censo de la Unión de Palmeadoras, julio-agosto de 2016

About two thirds (68 of 89) of palmeadoras use hybrid maize to make tortillas, particularly when native varieties are scarce: “when there is native maize, great, but when it is scarce, we have to grab the one that comes from outside” (Miguel A. Valle Bautista, personal communication, 2016). Hybrid maize is obtained from DICONSA and from private stores (Table 2). These stores offer a variety of prices depending on maize quality. The average cost is 5.70 $ kg-1. Maize sold by DICONSA, subsidized by the federal government, sells at 5.00 $ kg-1.

Table 2 Origin of hybrid maize. 

Origen Número de palmeadoras
Tiendas particulares 61 de 68
DICONSA 21 de 68

Fuente: censo de la UPT, julio-agosto de 2016.

To sum up, palmeadoras are key actors in the circulation, use and conservation of the native maize varieties produced in the region. Women buy directly from producers or distributors, thus stimulating the creation of short market chains. However, the native varieties that women need to make tortillas are not always available in Tlaxiaco. Maize shortage forces palmeadoras so seek hybrid varieties, usually sold in private or State-owned stores.

Nixtamalization process

Nixtamalization involves cooking maize in an alkaline solution based on calcium hydroxide Ca(OH)2 (limestone) that improves its sensory characteristics. Dough becomes malleable and its nutritional content increases (Bourges, 2013). Traditional nixtamalization consists of four stages:

undesirable elements (chaff, crop residues, rotten or damaged maize, stones, foreign seeds) are removed; b) maize is placed in a vessel with water and lime and exposed to fire for 50-90 min; c) maize is let to rest between 14 and 18 h; d) water is removed and maize is washed two or three times, expanding approximately 45% with moisture (Paredes et al., 2009).

The amount of lime is key for proper nixtamalization. If missing, maize becomes reddish (palmeadoras call it “chapulín”). If too much lime is used, the tortilla’s color and flavor are affected. The right amounts depend on the type of maize. Blue and red varieties are quickly “limed”: “blue maize is very delicate for lime, same as red” (Miguel A. Valle Bautista, personal communication, 2016). Both varieties have soft pericarp and easily absorb lime (Rimarachín et al., 2000; Fernández et al., 2013), as opposed to the white and yellow ones that tolerate lime better (Rangel-Meza et al., 2004).

Fire exposure allows maize to be nixtamalized and baked; maize should be cooked just enough to avoid dough deterioration. “When maize is raw, the tortilla gets seared and does not cook evenly” (Lucila Zárate Hernández, personal communication, 2017). On the other hand, “when maize is over -cooked, the dough does not look good” (Lucila Zárate Hernández, personal communication, 2017). Cooking time varies according to maize type: blues and reds must stay in the cooker for a maximum of 30 min, while yellows and whites last about an hour. Cooking process requires permanent monitoring.

Nixtamalized maize is let to cool down (Paredes et al., 2009). Palmeadoras pointed out that hybrid maize must be removed from water immediately in order to prevent lime absortion: “hybrid maize is still in the fire [and] you have to get it out because... it gets uglily limed” (Juana Aguilar, personal communication, 2016). The same may happen with blue and red native varieties.

When nixtamal is ready it is necessary to grind it and make the tortillas shortly after in order to prevent the dough from losing consistency, especially with hybrid maize: “when... we do not rush to grind, sometimes the dough loses consistency” (Josefina Reyes Santiago, personal communication, 2016). One way to solve this problem is to add MASECA (commercial) flour, not a good option since the tortilla ceases to be handmade and its flavor becomes too close to the product of tortillerías.

To sum up, women use specialized knowledge when transforming the maize grain into food. Genetic improvement through hybridization does not take into account characteristics such as nixtamalization, hardness and dough adhesiveness, cooking time, softness, tortilla flavor and durability. Instead, it focuses on the external appearance of the grain (Rangel-Meza et al., 2004; Méndez-Montalvo et al., 2005) . Gender-sensitive genetic improvement must enter into the kitchen and find out whether women really need such improvement. If so, efforts should be placed in reducing the duration and intensity of their work, rather than on the appearance of the grain.

Tortilla marketing

Table 3 shows the variety of tortillas that palmeadoras sell in the streets and markets of Tlaxiaco. Women distinguish even between maize seeds of the same color and the tortillas made with them: “you have to differentiate the yellow maize, there is a small one and there is a big one” (Ángela Hernández Hernández, personal communication, 2016). Special mention should be made of the tortillas that combine maize and wheat that the palmeadoras introduced into the market. “I was the first one... they sold very well and... they all started” (Flora Adelina Sánchez, personal communication, 2016). Others have diversified their production with totopos and picaditas. “There are ladies who... are dedicated to making... totopos. Those are made differently because you have to use a bit of lard” (Margarita Cruz González, personal communication, 2016).

Table 3 Tortilla diversity. 

Tipo de tortilla Número de palmeadoras
Blanca 84 de 89
Azul 66 de 89
Amarilla 42 de 89
Roja (colorada) 33 de 89
Con trigo 52 de 89
De trigo solo 7 de 89
Otras (picaditas y totopos) 3 de 89

Fuente: censo de la UPT, julio-agosto de 2016.

The type of maize used responds to the preferences of the clientele. White tortilla “is the one that sells the most”, although “they also ask for the colored one, the blue one, the reddish one, the yellow one” (Miguel A. Valle Bautista, personal communication, 2015). Blue tortilla is particularly requested: “if I have blue tortilla, they ran out soon, people like them a lot” (Eva León Ortiz, personal communication, 2015).

Palmeadoras have attempted to standardize the size of the tortilla in order to ensure their earnings. With a larger tortilla “there is no profit, almost all of us have the same size” (Emilia Mendoza, personal communication, 2015). Other than that, each woman puts in the market a unique product, made with a personal touch, depending not only on the maize variety but also on the tortilla thickness. Some palmeadoras are famous for the quality of their product: “a little while and it’s all over, they want more, there’s no more, I tell them, just the ones I can carry” (Flora Adelina Sánchez, personal communication, 2016).

Palmeadoras sell their tortillas seven days a week, from dawn to dusk. They are placed in different times and locations in order to better distribute profits between them. They have also agreed to sell at the same price: seven tortillas for $10.00. Tortillerías selling the kg at $13.00 have proliferated and represent a risk for palmeadoras. “In our selling location a modern machine has been placed, and this has affected us a lot” (Petra Cruz González, personal communication, 2015). Some tortillerías distribute their product in motorcycles: “I used to sell up to $100... 150... when motorcycles began to deliver tortillas from house to house, sales went down” (Micaela Vázquez, personal communication, 2015). Palmeadoras have talked to municipal authorities in order to control the growth of tortillerías. The president agreed to regulate their working schedule, but nothing to that effect has happened.

To sum up, Tlaxiaco is between tradition and modernity, in the redefinition of the kind of society that it wants to become. The palmeadora job exemplifies this crossroad.

Tortillerías expansion can lead to the disappearance of a tradicional craft that uses and protects native maize varieties. It comes as no surprise that the gatekeepers of this product are indigenous women, one of the less visible groups in national definitions of public policy. Table 4 shows women’s opinions regarding the present and future of their trade: 80 consider that tortillerias represent a threat, 50 think that it is increasingly difficult to make tortillas with native maize varieties. An overwhelming majority adopts as their own the famous phrase “without maize there is no country”. The future of both their trade and the grain in a context so adverse to Mexican peasantry remains to be seen.

Table 4 Women’s opinions. 

Opinión Las tortillerías pueden terminar
con el oficio
Cada vez es más difícil hacer tortilla
con maíz criollo
Sin maíz no hay país
Totalmente en desacuerdo 0 3 0
En desacuerdo 7 31 0
Me da igual 2 5 0
De acuerdo 57 42 48
Totalmente de acuerdo 23 8 41
Total 89 89 89

Fuente: censo de la UPT, julio-agosto de 2016.


Palmeadoras are important buyers of both native and hybrid maize varieties in Tlaxiaco. Native varieties are locally produced while hybrid ones are brought from other parts of the country and commercialized in stores. Women’s subsistence activities contribute to the circulation of various maize types and the conservation of local seeds.

Palmeadoras have specific knowledge on maize nixtamalization process, and their daily cooking practices have allowed for its permanence in a traditional way. Women are the most important actors in the transformation of maize into food, as shown in their wisdom regarding the cooking needs of each variety: blue and red varieties require more attention, while white and yellow ones tolerate lime concentrations better. Hybrid varieties present difficulties in achieving good nixtamalization, a situation that complicates women’s work. Moreover, tortillerías represent a threat to palmeadoras’ subsistence, so it is important to make their trade visible and defend it in the whole municipality.

Las integrantes de la UPT contribuyen a la construcción de la soberanía alimentaria a nivel local porque venden un artículo culturalmente adecuado que estimula la producción regional de maíz criollo a través de sistemas tradicionales de cultivo. Las actividades de las mujeres integran en una cadena corta de mercado a campesinos(as), distribuidores(as) de maíz y compradores(as) de tortillas. Sus habilidades y necesidades deben ser reconocidas en definiciones nacionales de política pública con el fin de avanzar en el logro de la equidad de género y la conservación de la agrobiodiversidad.

The members of UPT contribute to the construction of food sovereignty at the local level by selling a culturally appropriate item that stimulates the local production of native maize through traditional cultivation systems. Women’s activities integrate peasants, maize distributors and tortilla buyers in a short regional market chain. Women’s skills and needs must be acknowledged in public policy design in order to promote gender equity and the conservation of agrobiodiversity.

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Received: February 00, 2017; Accepted: May 00, 2017

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