title: Proton NMR relaxation study of swelling and gelatinisation process in rice starch-water samples.
abstract: Proton transverse magnetization decay curves of rice flour starch-water samples were measured and analysed for the presence of four components in the relaxation curve. T2 values were interpreted on the basis of the diffusive and chemical exchange model that provided evidence for extra granular bulk water and three more water populations whose relaxation rate is governed by diffusive and chemical exchange with starch components. The analysis of relaxation data provided information on dynamics of water molecules as well as on the size and dispersion of diffusive domains. Furthermore, by measuring solid to liquid ratio, transverse and longitudinal relaxation curves of starch-water mixtures at increasing temperatures - from 20 to 77°C - swelling and gelatinisation processes were monitored.
authors.affiliation: Department of Chemistry, University of Rome La Sapienza, Box 34, Roma 62, P.le Aldo Moro, 5, 00185 Roma, Italy.
authors.forename: Mena
authors.initials: M
authors.lastname: Ritota
authors.affiliation: Department of Chemistry, University of Rome La Sapienza, Box 34, Roma 62, P.le Aldo Moro, 5, 00185 Roma, Italy.
authors.forename: Raffaella
authors.initials: R
authors.lastname: Gianferri
authors.affiliation: Department of Chemistry, University of Rome La Sapienza, Box 34, Roma 62, P.le Aldo Moro, 5, 00185 Roma, Italy.
authors.forename: Remo
authors.initials: R
authors.lastname: Bucci
authors.affiliation: Department of Chemistry, University of Rome La Sapienza, Box 34, Roma 62, P.le Aldo Moro, 5, 00185 Roma, Italy. Electronic address: elvino.brosio@uniromal.it.
authors.forename: Elvino
authors.initials: E
authors.lastname: Brosio
keywords: Gelatinisation; Low-resolution NMR; Proton relaxation times; Rice starch; Swelling