Nixtamalization
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Nixtamalization (
Nixtamalized corn has several benefits over unprocessed grain: It is more easily ground, its
Lime and ash are highly alkaline: the alkalinity helps the dissolution of hemicellulose, the major glue-like component of the maize cell walls, and loosens the hulls from the kernels and softens the maize.[3] The tryptophan in corn proteins are made more available for human absorption, thus helping to prevent pellagra.[4]: §5.2
Some of the corn oil is broken down into emulsifying agents (monoglycerides and diglycerides), while bonding of the maize proteins to each other is also facilitated. The divalent calcium in lime acts as a cross-linking agent for protein and polysaccharide acidic side chains.[5]
While cornmeal made from untreated ground maize is unable by itself to form a dough on addition of water, the chemical changes in masa allow dough formation. These benefits make nixtamalization a crucial preliminary step for further processing of maize into food products, and the process is employed using both traditional and industrial methods in the production of tortillas and tortilla chips (but not corn chips), tamales, hominy, and many other items.
Etymology
In the
The labels on packages of commercially sold tortillas prepared with nixtamalized maize usually list corn treated with lime as an ingredient in English, while the Spanish versions list maíz nixtamalizado.
History
Mesoamerica
The process of nixtamalization was first developed in Mesoamerica, where maize was originally cultivated. There is no precise date when the technology was developed, but the earliest evidence of nixtamalization is found in Guatemala's southern coast, with equipment dating from 1200 to 1500 BC.[7]
How nixtamalization was discovered is not known, but one possibility may have been through the use of hot stones (see pot boiler) to boil corn in early cultures which did not have cooking vessels robust enough to put directly on fire or coals. In limestone regions like those in Guatemala and southern Mexico, heated chunks of limestone would naturally be used, and experiments show that hot limestone makes the cooking water sufficiently alkaline to cause nixtamalization. Archaeological evidence supporting this possibility has been found in southern Utah, United States.[8]
The
The nixtamalization process was very important in the early Mesoamerican diet, as there is very little
Spread
The spread of maize cultivation in the Americas was accompanied by the adoption of the nixtamalization process. Traditional and contemporary regional cuisines (including
The process has not substantially declined in usage in the Mesoamerican region, though there has been a decline in North America. Many Native North American tribes, such as the Huron, no longer use the process.[citation needed] In some Mesoamerican and North American regions, dishes are still made from nixtamalized maize prepared by traditional techniques. The Hopi produce sodium carbonate from ashes of various native plants and trees.[9][10] Some contemporary Maya use calcium salts in the form of ashes of burnt mussel shells or heated limestone.[11]
In the United States, European settlers did not always adopt the nixtamalization process, except in the case of hominy grits, though maize became a staple among the poor of the southern states. This led to endemic pellagra in poor populations throughout the southern US in the early 20th century.[12] A more varied diet and fortification of wheat flour, the other staple food, have essentially eliminated this deficiency.[13]
Process
Cooking
In the first step of nixtamalization, kernels of dried maize are
During cooking and soaking, a number of chemical changes take place in the grains of maize. Because plant cell wall components, including
Extraction
After cooking, the alkaline liquid (known as nejayote), containing dissolved hull, starch, and other corn matter, is decanted and discarded (or sometimes used for making
The prepared grain is called hominy or nixtamal. Nixtamal has many uses, contemporary and historic. Whole nixtamal may be used fresh or dried for later use. Whole nixtamal is used in the preparation of pozole, menudo, and other foods. Ground fresh nixtamal is made into masa (nixtamal dough) and used to make tortillas, tamales, and arepas. Dried and ground, it is called masa harina or instant masa flour, and is reconstituted and used like masa.
The term hominy may refer to whole, coarsely ground, or finely ground nixtamal, or to a cooked porridge (also called samp) prepared from any of these.
Enzymatic nixtamalization
An alternative process for use in industrial settings has been developed known as enzymatic nixtamalization, which uses protease enzymes to accelerate the changes that occur in traditional nixtamalization, a technique borrowed from modern corn wet-milling. In this process, corn or corn meal is first partially hydrated in hot water, so that enzymes can penetrate the grain, then soaked briefly (for approximately 30 minutes) at 50–60 °C (122–140 °F) in an alkaline solution containing protease enzymes. A secondary enzymatic digestion may follow to further dissolve the pericarp. The resulting nixtamal is ground with little or no washing or hulling.
By pre-soaking the maize, minimizing the alkali used to adjust the pH of the alkaline solution, reducing the cooking temperature, accelerating processing, and reusing excess processing liquids, enzymatic nixtamalization can reduce the use of energy and water, lower nejayote (alkaline wastewater) production, decrease maize lost in processing, and shorten the production time (to approximately four hours) compared to traditional nixtamalization.[20]
Impact on health
The primary nutritional benefits of nixtamalization arise from the alkaline processing involved. The processing renders the protein more digestible, allowing tryptophan to be absorbed by humans. Humans can convert tryptophan into niacin, thus helping to prevent pellagra. Other measures of protein quality are also improved.[4]: §5.2 It was originally thought that the anti-pellagra action stems from increased availability of niacin (compared to a hemicellulose-bound form called "niacytin"),[3] but multiple experiments have disproven this theory.[4]: §5.2
Secondary benefits can arise from the grain's absorption of minerals from the alkali used or from the vessels used in preparation. These effects can increase calcium (by 750%, with 85% available for absorption), iron, copper, and zinc.[3]
Nixtamalization significantly deactivates (by 90–94%)
References
- ^ Thigpen, Susan (October 1983). "Hominy – Mountain Recipe". The Mountain Laurel. Retrieved November 17, 2013.
- ISBN 978-3-642-00724-8. Retrieved April 12, 2019.
- ^ a b c d Wacher, Carmen (January 1, 2003). "Nixtamalization, a Mesoamerican technology to process maize at small-scale with great potential for improving the nutritional quality of maize based foods". Food Based Approaches for a Healthy Nutrition in Africa. Archived from the original on March 5, 2018.
- ^ ISBN 9789251030134. – Section 5.2 "Lime-treated maize (part II)", Section 8 "Improvement of maize diets"
- ISBN 978-0-684-80001-1. Retrieved January 23, 2013.
- ISBN 968-12-0049-7.
- ISBN 978-1-4419-0471-3.
- .
- ISBN 978-3-11-013474-2. Retrieved October 15, 2007.
- ISBN 978-0-313-32989-0. Retrieved October 15, 2007.
- ^ "Guatemalan Tortillas: How To Make Them And Why To Eat Them". Retrieved August 3, 2018.
- ISBN 9789251038185.
- ISBN 978-1-4200-0580-6.
- ISBN 978-0-87817-206-1.
- ^ "What is Hominy?". Retrieved January 31, 2011.
- ^ "Nixtamalization, a Mesoamerican technology". Retrieved January 31, 2011.[permanent dead link]
- ^ "Technological Limitations of the Nixtamalization Process". Archived from the original on July 14, 2011. Retrieved January 31, 2011.
- ^ "Selective Nixtamalization of Fractions of Maize Grain". Archived from the original on July 28, 2011. Retrieved January 31, 2011.
- ^ "What's the difference between corn meal and corn masa?". November 4, 2010. Archived from the original on July 13, 2011. Retrieved January 31, 2011.
- ^ US patent 6428828, Jackson, David S. & Sahai, Deepak, "Enzymatic process for nixtamalization of cereal grains", issued 2002-08-06, assigned to NuTech Ventures Inc
- Coe, Sophie. America's First Cuisines (1994). ISBN 0-292-71159-X
- Davidson, Alan. Oxford Companion to Food (1999), "Nixtamalization", p. 534. ISBN 0-19-211579-0
- Kulp, Karen and Klaude J. Lorenz (editors). Handbook of Cereal Science and Technology (2000), p. 670. ISBN 0-8247-8358-1
- McGee, Harold. On Food and Cooking, 2nd Edition (2004) p. 477-478 ISBN 0-684-80001-2
- Smith, C. Wayne, Javier Betrán and E. C. A. Runge (editors). Corn: Origins, History and Technology (2004) p. 275 ISBN 0-471-41184-1