title: Effects of CaCO3 treatment on the morphology, crystallinity, rheology and hydrolysis of gelatinized maize starch dispersions.
abstract: Using calcium salts instead of lime allows for an ecological nixtamalization of maize grains, where the negative contamination impact of the traditional lime nixtamalization is reduced. This work assessed the effects of calcium carbonate (0.0-2.0%w/w CaCO3) on the morphology, crystallinity, rheology and hydrolysis of gelatinized maize starch dispersions (GMSD). Microscopy analysis showed that CaCO3 changed the morphology of insoluble remnants (ghosts) and decreased the degree of syneresis. Analysis of particle size distribution showed a slight shift to smaller sizes as the CaCO3 was increased. Also, X-ray patterns indicated that crystallinity achieved a minimum value at CaCO3 concentration in the range of 1%w/w. GMSD with higher CaCO3 concentrations exhibited higher thixotropy area and complex viscoelastic behavior that was frequency dependent. A possible mechanism involved in the starch chain modification by CaCO3 is that starch may act as a weak acid ion exchanger capable of exchanging alcoholic group protons for cations (Ca(+2)).
authors.affiliation: Departamento de Biotecnología, Universidad Autónoma Metropolitana-Iztapalapa, Apartado Postal 55-534, Iztapalapa 09340, Mexico.
authors.forename: S
authors.initials: S
authors.lastname: Garcia-Diaz
authors.affiliation: Facultad de Ciencias, Universidad Autónoma del Estado de México, Campus El Cerrillo, Toluca 50200, Mexico. Electronic address: carmenhernandezjaimes@gmail.com.
authors.forename: C
authors.initials: C
authors.lastname: Hernandez-Jaimes
authors.affiliation: Departamento de Biotecnología, Universidad Autónoma Metropolitana-Iztapalapa, Apartado Postal 55-534, Iztapalapa 09340, Mexico.
authors.forename: H B
authors.initials: HB
authors.lastname: Escalona-Buendia
authors.affiliation: Centro de Desarrollo de Productos Bióticos, Instituto Politécnico Nacional, Yautepec 62731, Mexico.
authors.forename: L A
authors.initials: LA
authors.lastname: Bello-Perez
authors.affiliation: Departamento de Ingeniería de Procesos e Hidráulica, Universidad Autónoma Metropolitana-Iztapalapa, Apartado Postal 55-534, Iztapalapa 09340, Mexico.
authors.forename: E J
authors.initials: EJ
authors.lastname: Vernon-Carter
authors.affiliation: Departamento de Ingeniería de Procesos e Hidráulica, Universidad Autónoma Metropolitana-Iztapalapa, Apartado Postal 55-534, Iztapalapa 09340, Mexico.
authors.forename: J
authors.initials: J
authors.lastname: Alvarez-Ramirez
mesh_terms: D002119:Calcium Carbonate / Q000737:chemistry*; D005780:Gelatin; D006868:Hydrolysis; D012212:Rheology; D013213:Starch / Q000737:chemistry*; D003313:Zea mays / Q000737:chemistry*
chemical_list: D005780:Gelatin; D013213:Starch; D002119:Calcium Carbonate
keywords: Calcium carbonate; Chemical mechanisms; Crystallinity; Nixtamalization; Rheology