Effects of Modification Sequence on Structures and Properties of Hydroxypropylated and Crosslinked Waxy Maize Starch

Abstract

The effects of modification sequence on chemical structures and physicochemical properties of hydroxypropylated (HP) and crosslinked (XL) waxy maize starch were investigated. The physicochemical properties, including pasting, gelling, and thermal properties, were studied. The chemical structures of dual-modified starches and their beta-limit dextrins were characterized with high-performance liquid chromatography. The HP-XL starch had higher Brabender viscosity than did the XL-HP starch at both pH 7 and 3; however, both showed similar gelling properties. Significantly higher onset and peak gelatinization temperatures, gelatinization enthalpy, and lower retrogradation were observed for the HP-XL starch. The HP-XL starch also exhibited significantly higher beta-amylolysis limit and higher content of low molecular weight saccharides in its isoamylase-debranched starch, suggesting its structure was more accessible to enzymatic attack than the XL-HP starch. Structural analyses revealed different distribution patterns of modifying groups between the two modified starches. The results indicate that the modification sequence altered the susceptibility to enzymes, changed the locations of substitution, and modified the physicochemical properties of the HP and XL waxy maize starches.

Characterization of Acetylated Waxy Maize Starches Prepared under Catalysis by Different Alkali and Alkaline-Earth Hydroxides

“…The carbohydrate profiles of isoamylase-treated acetylated waxy maize starches and their β-limit dextrins were evaluated by high-performance size-exclusion chromatography (HPSEC) according to the methods of Kasemsuwan et al [8] with modifications [9]. The acetylated waxy maize starches (10 mg) were also treated with 5 mL 2% ethylenediaminetetraacetic acid (EDTA) solution, boiled for 20 min, precipitated with seven-fold volume of methanol, and then subjected to HPSEC analysis.…”

Properties and Structures of Flours and Starches from Whole, Broken, and Yellowed Rice Kernels in a Model Study

“…The gel strength of the gelatinized pastes prepared using the Brabender Viskograph-E was measured with a texture analyzer (TA-XT2i, Texture Technologies, Scarsdale, NY) after 12 days of storage at 5°C (Wang and Wang 2000).…”

“…The aqueous phase containing the carbohydrate component was filtered through a 5-µm membrane before analysis with high-performance size-exclusion chromatography (HPSEC) according to the method of Kasemsuwan et al (1995). Carbohydrate profiles of starch and isoamylase-debranched starch were also analyzed by HPSEC and high-performance anion-exchange chromatography with pulsed amperometric detection (HPAEC-PAD), respectively, with modifications (Wang and Wang 2000). A Waters HPSEC system consisted of a 515 HPLC pump with an injector of 100 µL sample loop, an in-line degasser, a 2410 refractive index detector maintained at 40°C, and a series of Shodex OHpak columns KB-802 and KB-804, and a guard column all maintained at 55°C with a column heater.…”

High‐Efficient Preparation of Cross‐Linked Cassava Starch by Microwave‐Ultrasound‐Assisted and its Physicochemical Properties

“…Cross‐linked starch is a type of modified starch that attracted considerable attention because of its high resistance to acids, alkalis, shears, and enzymes . This type of starch has been widely used in food, biomedicine, papermaking, and other industries.…”