Nixtamalization

An 1836 lithograph of tortilla production in rural Mexico
Bowl of hominy (nixtamalized corn kernels)

Nixtamalization (/ˌnɪkstəməlɪˈzeɪʃən/) is a process for the preparation of maize, or other grain, in which the grain is soaked and cooked in an alkaline solution, usually limewater (but sometimes aqueous alkali metal carbonates),[1] washed, and then hulled. The term can also refer to the removal via an alkali process of the pericarp from other grains such as sorghum.

Nixtamalized corn has several benefits over unprocessed grain: It is more easily ground, its nutritional value is increased, flavor and aroma are improved, and mycotoxins are reduced by up to 97–100% (for aflatoxins).[2]

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 is 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, nixtamalized cornmeal will form a dough, called masa. 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.

  1. ^ Thigpen, Susan (October 1983). "Hominy – Mountain Recipe". The Mountain Laurel. Retrieved November 17, 2013.
  2. ^ Doralinda Guzmán-de-Peña (2010). "The Destruction of Aflatoxins in Corn by "Nixtamalización"" (PDF). In M. Rai; A. Varma (eds.). Mycotoxins in Food, Feed and Bioweapons. Berlin Heidelberg: Springer-Verlag. pp. 39–49. doi:10.1007/978-3-642-00725-5_3. ISBN 978-3-642-00724-8. Retrieved April 12, 2019.
  3. ^ Cite error: The named reference researchgate was invoked but never defined (see the help page).
  4. ^ Cite error: The named reference fao92 was invoked but never defined (see the help page).
  5. ^ Harold McGee (2004). On Food and Cooking: The Science and Lore of the Kitchen. New York, New York (USA): Scribner. p. 478. ISBN 978-0-684-80001-1. Retrieved January 23, 2013.