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http://repositoriodigital.ipn.mx/handle/123456789/11706| Título : | On the State of Calcium in Nixtamalized Corn Grains |
| Fecha de publicación : | 16-ene-2013 |
| Editorial : | MONARCHLI THOI NC.U SA |
| Descripción : | The aim of the present contribution is to shed light on the role of Ca in the nixtamalization process of corn and its interactions with the grain components. X-ray energy-dispersive spectroscopy (EDS) of corn grains before and after their nixtamalization (alkaline cooking in an aqueous solution of Ca(OH)2) showed that Ca is mainly retained by the corn hull (pericarp) and by the germ. In this last component Ca is found as salts of fatty acids, due to a partial saponification of fats during alkaline cooking. Exrerimental evidence indicates that Ca incorporated to the endosperm during the nixtamalization process is forming inclusion compounds of Ca salts of fatty acids within the amylose helical structure. The ionic exchange of Ca by 57Fe in peri carp allows the recording of M6ssbauer spectra of this part of the corn grain. All M6ssbauer spectra show two different structural sites for Fe, and therefore for Ca, since EDS evidences that the ionic exchange of Ca for Fe effectively takes place. The observed isomer shift values correspond to iron coordinated to oxygen atoms as first neighbors. Calcium in nixtamalized peri carp could be coordinated by polyuronic acids from the hemicelluloses and/or by phenolic groups from alkaline lignin.. During the alkaline cooking hemicelluloses and lignin of corn hull are strongly degraded. |
| URI : | http://www.repositoriodigital.ipn.mx/handle/123456789/11706 |
| Otros identificadores : | http://hdl.handle.net/123456789/1246 |
| Aparece en las colecciones: | Doctorado |
Ficheros en este ítem:
| Fichero | Descripción | Tamaño | Formato | |
|---|---|---|---|---|
| 2000Libro-Tort 4.pdf | 117.08 kB | Adobe PDF | Visualizar/Abrir |
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