Nixtamalization
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).
[3] The tryptophan in corn proteins is made more available for human absorption, thus helping to prevent niacin deficiency pellagra.
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.
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.
[6] The term nixtamalization can also be used to describe the removal of the pericarp from any grain by an alkali process, including maize, sorghum, and others.
[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.
[citation needed] In some Mesoamerican and North American regions, dishes are still made from nixtamalized maize prepared by traditional techniques.
[9][10] Some contemporary Maya use calcium salts in the form of ashes of burnt mussel shells or heated limestone.
[13] In the first step of nixtamalization, kernels of dried maize are cooked in an alkaline solution at or near the mixture's boiling point.
Because plant cell wall components, including hemicellulose and pectin, are highly soluble in alkaline solutions, the kernels soften and their pericarps (hulls) loosen.
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 amate bark paper).
[15][16][17][18][19] This hulling is performed by hand, in traditional or very small-scale preparation, or mechanically, in larger scale or industrial production.
[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.
