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http://repositoriodigital.ipn.mx/handle/123456789/10613| Título : | Phase Transitions in Amylose and Amylopectin Under the Influence of Ca(OH)2 in Aqueous Solution |
| Autor : | Sanchez Sinencio, Feliciano |
| Palabras clave : | amylose amyliopectin calcium content |
| Fecha de publicación : | 16-ene-2013 |
| Editorial : | José Luis Fernández-Muñoz |
| Descripción : | Amylose (A1) and amylopectin (A2) are the two main constituent substances of most starches (75-80% in dry
cornstarch). Endosperm of corn kernel contains, in general, 28% A1 and 72% A2. During cooking of corn starch in
food preparation, specially those solved in water, the mixture of A1 and A2 experiences a phase transition from a pasty
and weak-tied wet masa to a completely consistent dry material (gelatinization). Cooked corn tortillas, from dough
prepared with 0.25% of Ca(OH)2 in weight (Mexico and Central America), have better mechanical, structural and
rheological properties, beside a more accepted flavor. In order to understand the mechanism of phase transformation of
wet dough of corn starch under the Ca(OH)2 presence, A1, A2 and 28%A1+72%A2 (A3) samples were prepared with and
without Ca(OH)2, which afterward were boiled. During this process part of Ca is incorporated in cooked samples. Xray
diffraction (XRD) analysis and thermal diffusivity (ƒ¿) measurements were carried out in six samples: Three
including Ca(OH)2 and other three without it. Thermal diffusivity data were achieved by means of a photoacoustic
system. XRD patterns show a more structured material when Ca2+ is present in the molecular structure of material. ƒ¿
data evidence an increase when Ca2+ is present in A1 and A2 samples, however, improves notably for the A3. This
result can indicate that Ca2+ enhances the crosslinking of polymeric chains, contributing to a better heat conduction. CICATA-IPN LEGARIA |
| URI : | http://www.repositoriodigital.ipn.mx/handle/123456789/10613 |
| Otros identificadores : | 8 1348-2246 http://hdl.handle.net/123456789/87 |
| Aparece en las colecciones: | Doctorado |
Ficheros en este ítem:
| Fichero | Descripción | Tamaño | Formato | |
|---|---|---|---|---|
| resumen.pdf | 104.04 kB | Adobe PDF | Visualizar/Abrir |
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