Essential to hominy is the process of nixtamalization (pronounced NEESH-ta-mal-i-za-shun). It’s a tricky word, and honestly, it’s a tricky process. For this reason, there’s a lot of misinformation about what nixtamalization is and exactly what it does.

Nixtamalization is a culinary technique that utilizes an alkaline substrate in order to process and cook maize. The practice itself involves soaking dried maize kernels to a solution made from water and an alkaline substrate, like limestone or lye, then cooking the kernels, or boiling the kernels in an alkaline solution for several hours. This practice accomplishes several things: soaking dried maize kernels in an alkaline solution makes it easier to remove the thin outer seed coat, or pericarp, that encases the kernel, either through grinding or by rubbing. Next, both alkalinity and heat treatment help to not only soften the kernel, but also chemically alter the endosperm and germ of cooked maize, creating a nutritious and complete dietary staple (Bressani et al. 1958; Bressani and Scrimshaw 1958). Finally, nixtamalization flavors maize, altering the taste profile of the kernels, giving them a slightly bitter and earthy flavor (Briggs 2015).

Certain variants of maize, in particular flints but also some flour varieties, are well adapted for being nixtamalized (King 1994:38). Flints and pops have hard outer seed coats that limit how much water the endosperm can absorb, which in turn limits the softness and nutrition of the final product. This is because maize is a descendant of the grass teosinte, and like all grasses, is not easily digested by humans. While cows and other ruminants have no problem digesting corn and extracting nutrients from the kernels, for humans, non-nixtamalized corn passes straight through our digestive tract. While flour varieties of maize also have an outer seed coat, it isn’t quite as hard.

The Magic

Nixtamalizing maize accomplishes several things: first, after soaking kernels in an alkaline solution overnight (with a pH of 10.9 or higher; Pappa et al. 2010), the outer seed coat begins to soften and even dissolve. After rinsing the kernels, you can completely remove the hull either through grinding or, in the case of softer variants, by rubbing. When making both masa and coarsely-cracked hominy, the hull is removed by grinding–with masa, the hull is crushed with the rest of the kernel, but with cracked hominy, a fanner is used to remove the hulls.

At this point, though, the germ and perhaps some of the endosperm still has a tough, crunchy texture, and is not yet very nutritious. The saturated kernels need to be heat-treated, or boiled, for at least thirty minutes (Bressani and Scrimshaw 1958). The combination of heat and alkalinity alters the biochemistry of the kernel. While maize kernels are high in several essential amino acids and B vitamins, including niacin, these are tightly locked within the germ of the kernel (Bressani et al. 1958), and when raw, are indigestible for humans. Nixtamalization chemically alters maize, releasing these essential vitamins stored within the endosperm and germ of the kernel, while also decreasing the solubility of the zein protein, which is the nutritionally poorest part of the kernel.

The nutritional enhancement of maize through nixtamalization is absolutely incredible. It transforms maize from a plant that provides few nutrients to one that is capable of serving as a complete dietary staple for human populations. Few foods are complete dietary staples, meaning that they provide enough nutrition for a population to safely derive over 40% of their calories and live happy, healthy lives. Nixtamalized maize is one such food. Conversely, a population subsisting primarily on untreated maize is not deriving their calories from a complete food, and as such will receive none of the health benefits of plant.

History

Nixtamalization is a very old culinary practice, dating back thousands of years. Archaeologically, we use comals, or the stone rolling platform used to make masa, and other materials as proxies for the practice, which begin to regularly appear at least 2,500 B.P. However, a nixtamalizing maize foodway may not have been the first widespread maize-based foodway. Some researchers propose that early maize may have first been fermented and consumed in a beverage form, and thus disseminated as a social drink (Bonzani and Oyuela-Caycedo 2006).

Historically, the practice was first recorded among the Aztec by Bernardino de Sahagun (Coe 1994). The word itself is a Spanish version of a Nahuatl word, used in reference to the practice of alkalizing then grinding maize to make masa. The practice of alkaline treating maize, however, was widespread throughout the Americas, and though we can trace its earliest roots to Mesoamerica, it took on certain idiosyncrasies as it was disseminated and adopted in tandem with maize. For example, in the Southwestern United States, nixtamalizing practices used ashes made from local plants, such as juniper, as the alkalizing substrate, altering the taste of the final product (Beck 2001). In addition, Southwestern groups, after centuries of growing and raising maize, developed their own variants that were best suited to their culinary tastes. (A number of these variants are still being cultivated.)

By the time maize was disseminated into the Eastern United States, it was completely divorced from the tortilla making tradition. As such, Indians in the Southeast were not making tortillas, but instead were primarily making a corn stew or porridge, very different from the pozole or masa of Mexico, and what became the direct culinary descendent of hominy. Maize was still nixtamalized, but instead of using lime or limestone, they used hardwood ash or lye made from hardwood ash. This ancestral hominy was their primary dietary mainstay (Hudson 1979).

While other Indian groups throughout the Americas had practices that we would today consider nixtamalizing practices (Katz et al. 1974), they were not always recognized as such. In the Eastern Woodlands, for example, many colonists witnessed the use of woodash or woodash lye when Indians coked maize, but did not interpret the practice as either similar to the use of cal in Mesoamerica, nor as an important culinary practice (Briggs 2015). Instead, they interpreted the practice solely as one used to flavor the maize, giving it a taste which many Europeans found distasteful.

Columbian Exchange

Maize was one of the items brought back to Europe by Christopher Columbus after his first trip to the Americas. Maize is from the Taino word mahiz, the name the Arawaks used for their staple grain (Fussel 1999). (Corn, on the other hand, is an English word that simply means “grain.” Historically, it was used to refer to various kinds of plants, including wheat and barley and yes, maize. As such, the “corn” referred to in the Old Testament, the one in which Ruth stands in, is not a field of maize, but instead a field of wheat.)

After being exported to Europe, maize was rapidly adopted and within a few decades was being grown in great quantities. In fact, this process happened so quickly that by the early sixteenth century, most maize eaten in Europe was grown and exported from Turkey, earning the plant the nickname “Turkish wheat” (Fussell 1999). This nickname resulted in a several centuries of confusion regarding the origins of maize, leading many to believe the plant, in fact, originated in Eastern Europe.

Sadly, at the expense of many lives, only the plant, divorced from a nixtamalizing culinary practice, was exported back to Europe. As mentioned, populations that subsist on large quantities of maize that has not been nixtamalized will suffer rampant malnutrition. This particular form of malnutrition manifests as pellagra, a chronic wasting disorder. Pellagra is an Italian word that references the roughened skin which develops later in the course of the disease. Symptoms range from chronic dermatitis, diarrhea, dementia, and if left untreated, will result in death (Chacko 2005; Hegyi et al. 2003). The first recorded case of pellagra was in 1762 in the Asturias region of northern Spain, where the disease had been rampant in peasant populations for over three decades (Osborn 1988). This pattern was repeated throughout Europe as various other peasant populations turned to maize when other staple crops failed (Fussell 1999).

During the Great Depression, pellagra outbreaks were recorded throughout the American South. Because many American settlers were first introduced to maize in Europe, they were never unfamiliar with the practice of nixtamalization. Even after immigrating, many preferred to make maize the way they had been taught as children, and thus never adopted a nixtamalizing practice. This resulted in nearly three decades of rampant, untreated pellagra throughout the American South, with over three million documented cases and at least 100,000 attributed deaths (Bollet 1992; Chacko 2005).

How Did Ancient People Learn to Nixtamalize Their Maize?

This is a question I get asked all the time.

Alkaline cooking is not unique to the Americas. Throughout history, there have been a number of other “independent” inventions of culinary techniques that utilize alkaline substrates. For example, within the Scandinavian culinary tradition, lutefisk, fermented stockfish or salted whitefish, is a centuries old traditional food made by soaking the fish for approximately two weeks in a solution made from water and lye (McGee 2004:231-232). In the Chinese culinary tradition, pidan, or the thousand-year-old-egg, is an egg, typically duck, that has been preserved by coating it in a clay/salt/alkaline mixture (McGee 2004:116). Olives have been and still are routinely cured using lye in order to reduce the amount of time it takes to fix the the extraordinarily bitter phenolic substance oleuropein found within the fruit. In Roman times, olives were traditionally fermented in wood ashes, which successfully cured olives in a matter of hours (McGee 2004:295). And in the present, lye is still routinely used to make pretzels, giving them their characteristic shiny brown finish.

The list goes on.

My point is that while it may seem strange to use lye or any alkaline substance in our own cooking, this has, historically, not been the case. For thousands of years, people have been experimenting with the natural world around them, learning how it works and how they can make it work for them. Numerous groups at various times discovered that alkaline substances can be used to ferment, to preserve, and to detoxify.

However, I haven’t really answered the question, have I? The short of it is that no one really knows. Personally, I think that the relationship between maize and alkaline cooking may have begun as a way to divest the kernel of its seed coat, or perhaps as a technique to destroy any bacteria or fungus that may have grown on the grain (woodash and lye are both excellent fungicides). Clearly, some groups observed that  nixtamalized maize is better for you than non-nixtamalized maize, but I think for most of its history, the actual health benefits of the practice were not known. Instead, the perpetuation of the practice was owed to at least two features of the practice: first, maize soaked in an alkaline substrate is easier to grind than maize simply soaked in water.

Second, and what I think is most important, is that nixtamalization flavors maize. Ask any hominy, tortilla, or tortilla chip connoisseur and they’ll tell you that nixtamalized maize taste different than non-nixtmalized. This is a taste that many European colonists commented on, and most did not find it appealing (Briggs 2015). I’ve attributed an inclination for this taste, as well as the cultural and social associations of the food, to the perpetuation of the hominy foodway throughout most of the historic native Eastern Woodlands. Importantly, despite the introduction of baking soda (a less-caustic alternative to lye) and the introduction of complementary foodstuffs (like the common bean), a nixtamalizing hominy foodway was practiced by numerous Indian groups well into the early twentieth century, with woodash lye featuring prominently in many maize dishes.

References:

Beck, Margaret. 2001. Archaeological Signatures of Corn Preparation in the U.S. Southwest. Kiva 67(2):187-218.

Bollet, A. J. 1992. Politics and Pellagra: the Epidemic of Pellagra in the U.S. in the Early Twentieth Century. Yale Journal of Biological Medicine 65(3):211-221.

Bonzani, Renee M., and Augusto Oyuela-Caycedo. 2006. The Gift of the Variation and Dispersion of Maize: Social and Technological Context in Amerindian Societies. In Histories of Maize, edited by John E. Staller, Robert H. Tykot, and Bruce C. Benz, pp. 344-356. Academic Press, Burlington.

Bressani, Ricardo, and Nevin S. Scrimshaw. 1958. Effect of Lime Treatment on in Vitro Availability of Essential Amino Acids and Solubility of Protein Fractions in Corn. Journal of Agricultural and Food Chemistry 6(10):774-778.

Bressani, Ricardo, R. Paz y Paz, and Nevin S. Scrimshaw. 1958. Chemical Changes in Corn During Preparation of Tortillas. Journal of Agricultural and Food Chemistry 6(10):770-774.

Briggs, Rachel V. 2015. The Hominy Foodway of the Historic Native Eastern Woodlands. Native South 8(1):112-146.

Chacko, Elizabeth. 2005. Understanding the Geography of Pellagra in the United States: The Role of Social and Place-Based Identities. Gender, Place, and Culture 12(2):197-212.

Coe, Sophie D. 1994. America’s First Cuisines. University of Texas Press, Austin.

Fussell, Betty. 1999. Translating Maize Into Corn: The Transformation of America’s Native Grain. Social Research 66(1):41-65.

Hegyi, Juraj, Robert A. Schwartz, and Vladimir Hegyi. 2004 Pellagra: Dermatitis, Dementia, and Diarrhea. The International Journal of Dermatology 43:1-5.

Hudson, Charles. 1976. The Southeastern Indians. University of Tennessee Press, Knoxville.

Katz, Solomon H., M. L. Hediger, L. A. Valleroy. 1974. Traditional Maize Processing Techniques in the New World. Science, New Series 184: 765-773.

King, Francis. 1994. Variability in Cob and Kernel Characteristics of North American Maize Cultivars. In Corn and Culture in the Prehistoric New World. Sissel Johannessen and Christine Hastorf, ed. Pp. 35-54. Westview Press, Boulder.

McGee, Harold. 2004. On Food and Cooking: The Science and Lore of the Kitchen. Scribner, New York.

Osborn, Alan. 1988. Limitations of the Diffusionist Approach: Evolutionary Ecology and Shell-Tempered Ceramics. In The Transfer and Transformation of Ideas and Material Culture. P. J. Hugill and D. B. Dickson, ed. Pp. 23-44. Texas A&M University Press, College Station.

Pappa, María Renée, Patricia Palacios de Palomo, and Ricardo Bressani. 2010. Effect of Lime and Wood Ash on the Nixtamalization of Maize and Tortilla Chemical and Nutritional Characteristics. Plant Foods and Human Nutrition 65(2):130-135.

Wright, Muriel H. 1958.  American Indian Corn Dishes. The Chronicle of Oklahoma 36:155–166.