Molecular and granular characteristics of corn starch modified by HCl-methanol at different temperatures
Journal
Carbohydrate Polymers
Journal Volume
63
Journal Volume
63
Journal Issue
4
Journal Issue
4
Pages
527-534
Start Page
527
End Page
534
ISSN
01448617
Date Issued
2006-03-18
Author(s)
Chung, Yi-Lin
Abstract
Native corn starch was hydrolyzed with 0.36% HCl in methanol at 25 and 45 °C for periods of time up to 240 h. The action of acid penetration and hydrolysis was investigated by confocal laser scanning microscopy (CLSM), scanning electron microscopy (SEM), high-performance anion-exchange chromatography (HPAEC) and high-performance size-exclusion chromatography (HPSEC) equipped with viscometry, right-angle laser light scattering (RALLS) and refractive index (RI) detectors. Corn starch hydrolyzed at 45 °C for 240 h showed strong intensity of APTS (8-amino-1,3,6-pyrenetrisulfonic acid) fluorescence and sharp growth ring structure. Exocorrosion over the surface of corn starch was only observed on the corn starch hydrolyzed at 25 °C for 240 h and observed on all corn starch hydrolyzed at 45 °C. The Mw and Rh of acid-hydrolyzed corn starch decreased with increasing the degree of hydrolysis. The acid hydrolysis rate in methanol of corn starch was mainly dependent on the temperature, which dominated the penetration efficiency of acid.
Subjects
Acid-methanol treatment
Confocal laser scanning microscopy
Corn starch
Starch granule
Type
journal article