title: The retrogradation properties of glutinous rice and buckwheat starches as observed with FT-IR, 13C NMR and DSC.
abstract: The experiment was conducted to study the retrogradation properties of glutinous rice and buckwheat starch with wavelengths of maximum absorbance, FT-IR, (13)C NMR, and DSC. The results show that the starches in retrograded glutinous rice starch and glutinous rice amylopectin could not form double helix. The IR results show that protein inhabits in glutinous rice and maize starches in a different way and appearance of C-H symmetric stretching vibration at 2852 cm(-1) in starch might be appearance of protein. Retrogradation untied the protein in glutinous amylopectin. Enthalpies of sweet potato and maize granules are higher than those of their retrograded starches. The (13)C NMR results show that retrogradation of those two starches leads to presence of β-anomers and retrogradation might decompose lipids in glutinous rice amylopectin into small molecules. Glutinous rice starch was more inclined to retrogradation than buckwheat starch. The DSC results show that the second peak temperatures for retrograded glutinous rice and buckwheat starches should be assigned to protein. The SEM results show that an obvious layer structure exists in retrograded glutinous rice amylopectin.
authors.affiliation: Tianjin Key Laboratory of Food Biotechnology, School of Biotechnology and Food Science, Tianjin University of Commerce, Tianjin 300134, PR China; College of Light Industry and Food Sciences, South China University of Technology, Guangzhou 510640, PR China; Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety, Guangzhou 510640, PR China. Electronic address: lianliu2002@163.com.
authors.forename: Xijun
authors.initials: X
authors.lastname: Lian
authors.affiliation: Tianjin Key Laboratory of Food Biotechnology, School of Biotechnology and Food Science, Tianjin University of Commerce, Tianjin 300134, PR China.
authors.forename: Changjun
authors.initials: C
authors.lastname: Wang
authors.affiliation: Tianjin Key Laboratory of Food Biotechnology, School of Biotechnology and Food Science, Tianjin University of Commerce, Tianjin 300134, PR China.
authors.forename: Kunsheng
authors.initials: K
authors.lastname: Zhang
authors.affiliation: College of Light Industry and Food Sciences, South China University of Technology, Guangzhou 510640, PR China; Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety, Guangzhou 510640, PR China. Electronic address: felinli@scut.edu.cn.
authors.forename: Lin
authors.initials: L
authors.lastname: Li
mesh_terms: D002152:Calorimetry, Differential Scanning; D019612:Fagopyrum / Q000737:chemistry*; D019906:Nuclear Magnetic Resonance, Biomolecular; D012275:Oryza / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D013213:Starch / Q000737:chemistry* / Q000648:ultrastructure
chemical_list: D013213:Starch
keywords: Buckwheat starch; Glutinous rice starch; Retrogradation properties