Understanding the structural features of high-amylose maize starch through hydrothermal treatment

Abstract

Understanding the structural features of high-amylose maize starch through hydrothermal treatment, International Journal of Biological Macromolecules http://dx.doi.org/10.1016/j.ijbiomac. 2015.12.033 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. Abstract:In this study, high-amylose starches were hydrothermally-treated and the structural changes were monitored with time (up to 12 h) using scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM), small-angle X-ray scattering (SAXS), X-ray diffraction (XRD), and differential scanning calorimetry (DSC). When high-amylose starches were treated in boiling water, half-shell-like granules were observed by SEM, which could be due to the first hydrolysis of the granule inner region (CLSM). This initial hydrolysis could also immediately (0.5 h) disrupt the semi-crystalline lamellar regularity (SAXS) and dramatically reduce the crystallinity (XRD); but with prolonged time of hydrothermal treatment (≥ 2 h), might allow the perfection or formation of amylose single helices, resulting in slightly increased crystallinity (XRD and DSC). These results show that the inner region of granules is composed of mainly loosely-packed amylopectin growth rings with semi-crystalline lamellae, which are vulnerable under gelatinization or hydrolysis. In contrast, the periphery is demonstrated to be more compact, possibly composed of amylose and amylopectin helices intertwined with amylose molecules, which require greater energy input (higher temperature) for disintegration.

Composition, structure and physicochemical properties of three coloured potato starches

“…Ten milligrams of starch was stained with 10 lL freshly-prepared APTS solution (20 mM, with 15% acetic acid solution as the solvent) and 10 lL 1 M sodium cyanoborohydride solution. The mixture was sealed and placed in a dark condition at 30°C for 15 h. After thoroughly washing the stained starch granules with deionised water five times, the granules were suspended in 0.5 mL of 50% water/glycerol solution and visualised using a confocal laser scanning microscope (CLSM; FV1000, Olympus Corporation, Japan) equipped with a 60/1.3 oil objective lens (Maaran et al, 2014;Yang et al, 2015). The excitation wavelength was 488 nm, and the emission wavelength range was 500-600 nm.…”

Investigation of rheological properties and conformation of cassava starch in zinc chloride solution

“…The other two concentrations, 35% and 45%, were used to enlarge the differences between samples. The ZnCl 2 solution was then mixed with a certain amount of starch (1,2,3,4, and 5 wt%, dry weight). Afterward, the system was stirred at 50°C for 4 h to achieve complete dissolution [5].…”

Starch–zinc complex and its reinforcement effect on starch-based materials

“…Starch is a renewable resource that is abundant in nature (Xie, Pollet, Halley, & Avérous, 2013;Yang et al, 2016) and has been used in chemical, food, pharmaceutical and petroleum industries (Bie et al, 2013;Tang et al, 2015). Moreover, because of the environmental concerns and waste management, there has been ongoing research for replacing conventional non-biodegradable plastics with natural biopolymers such as starch (Iamareerat, Singh, Sadiq, & Anal, 2018;Nagy et al, 2017).…”