title: A comparative study of the characteristics of cross-linked, oxidized and dual-modified rice starches.
abstract: Rice starch was cross-linked with epichlorohydrin (0.3%, w/w, on a dry starch basis) and oxidized with sodium hypochlorite (2.5% w/w), respectively. Two dual-modified rice starch samples (oxidized cross-linked rice starch and cross-linked oxidized rice starch) were obtained by the oxidation of cross-linked rice starch and the cross-linking of oxidized rice starch at the same level of reagents. The physicochemical properties of native rice starch, cross-linked rice starch and oxidized rice starch were also studied parallel with those of the two dual-modified rice starch samples using rapid visco analysis (RVA), differential scanning calorimetry (DSC), dynamic rheometry and scanning electron microscopy (SEM). It was found that the levels of cross-linking and oxidation used in this study did not cause any significant changes in the morphology of rice starch granules. Cross-linked oxidized starch showed lower swelling power (SP) and solubility, and higher paste clarity in comparison with native starch. Cross-linked oxidized rice starch also had the lowest tendency of retrogradation and highest ability to resistant to shear compared with native, cross-linked, oxidized and oxidized cross-linked rice starches. These results suggest that the undesirable properties in native, cross-linked and oxidized rice starch samples could be overcome through dual-modification.
authors.affiliation: National Engineering Laboratory for Rice and By-product Further Processing, Central South University of Forestry & Technology, Changsha, China. xiaoxijingjing@163.com
authors.forename: Hua-Xi
authors.initials: HX
authors.lastname: Xiao
authors.forename: Qin-Lu
authors.initials: QL
authors.lastname: Lin
authors.forename: Gao-Qiang
authors.initials: GQ
authors.lastname: Liu
authors.forename: Feng-Xiang
authors.initials: FX
authors.lastname: Yu
mesh_terms: D002152:Calorimetry, Differential Scanning; D004811:Epichlorohydrin / Q000737:chemistry; D012275:Oryza / Q000737:chemistry*; D010084:Oxidation-Reduction; D012995:Solubility; D013213:Starch / Q000737:chemistry*
chemical_list: D004811:Epichlorohydrin; D013213:Starch