Water Binding in Gelatinized Nonglutinous and Glutinous Rice Starch Determined by Pulsed NMR
1980 Volume 31 Issue 8 Pages 541-545
Details
1980 Volume 31 Issue 8 Pages 541-545
Proton spin relaxation times T1 and T2 in gelatinized nonglutinous and glutinous rice starch were measured at 32°C by pulsed NMR. Dependence of T1 and T2 on water content was analyzed in accordance with a theory of Zimmerman on the assumption of two states of water; one is free and the other is bound. The correlation times of bound water were obtained for each water con- tent. The bound water fraction, p, was determined as a function of the total water content, w (gW/gDM), for the both gelatinized starch.
1/p= 16.9ω-4.3 for nonglutinous gel
1/p= 22.8ω-12.5 for glutinous gel
Diffusion of water molecule was suggested in echo signal for the specimens containing more water than 2 g/gDM for the both starch.
