Analysis of moisture changes during rice seed soaking process using low-field NMR

Low field nuclear magnetic resonance (LF-NMR) has the technique advantages of nondestructive and non-invasive, which can be used to study the variation, distribution and flow of different phase state moisture in rice seed through the detection of proton's density and distribution in samples. In this paper, Shennong No. 9816 and No. 9903 rice seeds were used in the study. The center frequency and pulse width were determined using the FID pulse sequence in the NMR spectroscopic analysis software. The low field NMR technique and dynamic detection of the CPMG pulse sequence signal were used to determine the spin relaxation time of samples (the transverse relaxation time T[sub 2]). The variation of moisture content can reflect the physical and chemical reactions in rice seed during soaking process. This experiment proposed anon-destructive rice seed moisture content detection method, which can reveal the moisture variation more directly and accurately during seed soaking, thus the results can be used to determine