Effect of extrusion treatment on the thermal stability and structure of corn starch with different emulsifiers

Abstract

Corn starch was treated with raw moisture (30%), screw speed (160 rpm), extrusion temperature (30, 55, 80, 105, 130, and 155°C), and emulsifier (1.2%) to produce the starch extrudate particles in a twin screw extruder. The influence of extrusion processing and composition (starch and emulsifier content) on the viscosity, microstructure, solubility, swelling power, and thermal stability of starch extrudate particles was examined. The SEM results showed that the surface of starch extrudate particles was quite irregular and a fissure could be clearly observed. The X-ray intensities and relative crystallinity were decreased after extrusion treatment. The data highlighted that the gelatinisation temperature and solubility were increased and the gelatinisation enthalpy, viscosity, and swelling power were decreased. The emulsifiers present also influenced the thermal stability and solubility of starch extrudate particles, which were attributed to their ability to modify starch granule interactions. The thermogravimetric analysis and differential scanning calorimetry analysis indicated that the thermal stability of starch extrudate particles was improved after extrusion processing.

Optimization of an Extrusion Cooking Process to Increase Formation of Resistant Starch from Corn Starch with Addition of Citric Acid

“…Figure c reveals the best treatment for RS production: 18% moisture content and 5.1% of citric acid with the yield of 1.15 g 100 g −1 (Table ), and Figure d shows the optimized conditions of ECP at 21.4% moisture content with 2.18% of citric acid, generating RS at 0.85 g 100 g −1 ( Figure ); both treatments were carried out at 127 °C and 233 rpm. As presented in Figure c,d, the granular structure of corn starch was destroyed and generated amorphous structures owing to gelatinization and dextrinization of starch because of high temperature, mechanical stress, and high pressure during extrusion . RS is visible on the surface of the structures in the form of a dense aggregate due to the leaching of amylose out of the starch granules during ECP …”

“…As presented in Figure 4c,d, the granular structure of corn starch was destroyed and generated amorphous structures owing to gelatinization and dextrinization of starch because of high temperature, mechanical stress, and high pressure during extrusion. [2,13,27,43] RS is visible on the surface of the structures in the form of a dense aggregate due to the leaching of amylose out of the starch granules during ECP. [37,44]…”

Synthesis of triethylene tetramine–modified water‐insoluble corn flour caged in magnetic chitosan resin and its adsorption application for removal of patulin from apple juice

“…It is well known that, chitosan exhibits characteristic peaks at 2θ = 10° and 20°, and the XRD pattern of the native corn starch shows peaks at 2θ of 15°, 17°, 18°, and 23° (Gutha, Janak, Zhang, Zhang, & Xu, 2017; Yang et al., 2015). It can be seen that the peak of chitosan at 2θ = 10° and almost all characteristic crystalline peaks of native corn starch disappeared in the XRD of TETA‐WICF/MCR (shown in Figure 1D).…”

Physicochemical and Morphological Properties of Extruded Adlay (Coix lachryma-jobi L) Flour

“…It was observed that most of the native starch granules were spherical, elliptical, and polygonal, with a particle distribution size of 5-16 μm, similar to that of most other grains. Scanning Journal of Chemistry electron microscopy displayed cracking of starch granules with extrusion [38]. e microstructure and particle morphology of the powder may be related to changes in extrusion parameters.…”