title: Characterization of Oat (Avena nuda L.) β-Glucan Cryogelation Process by Low-Field NMR.
abstract: Low-field nuclear magnetic resonance (LF-NMR) is a useful method in studying the water distribution and mobility in heterogeneous systems. This technique was used to characterize water in an oat β-glucan aqueous system during cryogelation by repeated freeze-thaw treatments. The results indicated that microphase separation occurred during cryogelation, and three water components were determined in the cryostructure. The spin-spin relaxation time was analyzed on the basis of chemical exchange and diffusion exchange theory. The location of each water component was identified in the porous microstructure of the cryogel. The pore size measured from the SEM image is in accordance with that estimated from relaxation time. The formation of cryogel is confirmed by rheological method. The results suggested that the cryogelation process of the polysaccharide could be monitored by LF-NMR through the evolution of spin-spin relaxation characteristics.
authors.affiliation: College of Biological Science and Engineering, Fuzhou University , Fuzhou, Fujian 350116, People's Republic of China.
authors.forename: Jia
authors.initials: J
authors.lastname: Wu
authors.affiliation: College of Biological Science and Engineering, Fuzhou University , Fuzhou, Fujian 350116, People's Republic of China.
authors.forename: Linlin
authors.initials: L
authors.lastname: Li
authors.affiliation: College of Biological Science and Engineering, Fuzhou University , Fuzhou, Fujian 350116, People's Republic of China.
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Wu
authors.affiliation: College of Biological Science and Engineering, Fuzhou University , Fuzhou, Fujian 350116, People's Republic of China.
authors.forename: Qiaoling
authors.initials: Q
authors.lastname: Dai
authors.affiliation: College of Biological Science and Engineering, Fuzhou University , Fuzhou, Fujian 350116, People's Republic of China.
authors.forename: Ru
authors.initials: R
authors.lastname: Zhang
authors.affiliation: College of Food Science, Fujian Agriculture and Forestry University , Fuzhou, Fujian 350002, People's Republic of China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D018554:Avena / Q000737:chemistry*; D005615:Freezing; D009682:Magnetic Resonance Spectroscopy; D016062:Porosity; D012212:Rheology; D014867:Water / Q000737:chemistry; D047071:beta-Glucans / Q000737:chemistry*
chemical_list: D047071:beta-Glucans; D014867:Water
keywords: LF-NMR; SEM; cryogelation; oat; rheology; water distribution; β-glucan