NMR Technique Application in Evaluating the Quality of Navel Orange During Storage

Low field nuclear magnetic resonance (NMR) technique was used to evaluate the quality and behavior of water in navel orange during the course of storage. Carr-Purcell-Meiboom-Gill (CPMG) sequence was used to acquire the samples' NMR echo signals. The spin-spin relaxation time (T-2) of samples were calculated by A mult-exponential regress model during the deferent period of storage until decay. A trend of T-2 variation was observed in the diagram T-2 vs. storage time. T-2 values arise in the initial stage and then changed little in the following steady period and fall quickly at the end before the samples decay during the period of storage. A T-2 declining quickly processing before decay were observed in nearly all samples. This method would be helpful for evaluating the quality of navel orange and the effect of preserving agent during storage in the future. (C) 2012 Published by Elsevier Ltd. Selection and/or peer-review under responsibility of Society for Resources, Environment and Engineering