Relaxation Time Distribution of Thai Rice Kernels During Growth Process


  • Klitsadee Yubonmhat Student, Doctor of Philosophy Program in Physics, Faculty of Science, Khon Kaen University, Thailand
  • Wiwat Youngdee Associate Professor, Department of Physics, Faculty of Science, Khon Kaen University, Thailand


Relaxation time distribution, Thai rice kernel, NMR


 Transverse relaxation time (T2) distributions of Thai rice kernels during grain development were investigated using time-domain NMR technique and Inverse Laplace Transform (ILT) method for analysis. During the early stages, 4–7 days after flowering (DAF), the T2 distributions revealed that most of water protons exhibit long relaxation times, while a small number of the protons show the short relaxation times. During the grain development from 10 to 16 DAF, the starchy endosperm in the grains increases. It was found that water protons showing long relaxation times decreased, while those exhibiting short relaxation times increased. From 16 to 49 DAF, the T2 distributions showed a slight changes. At 52 DAF, the distribution in the grains was very sensitive and changed significantly, and the existence of protons of the macromolecules (starch) were presented highly at this stage.


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