Abstract:

Information about water mobility and distribution in meat can be provided by proton nuclear magnetic resonance
(NMR) relaxometry. The suitable measurement parameters of low-field proton nuclear magnetic resonance (LF-NMR)
relaxometry will not only be helpful for the reliability of experiment data, which reflect accurately the information on the
sample, but also be beneficial for enhancing the detection efficiency. In this study, using fresh lean pork from the hind
legs, the effects of LF-NMR parameters on the accuracy, stability and reproducibility of the experimental results were
investigated. No significant changes in experimental data (P > 0.05) were observed when the tR (repetition delay) and Echo
Count (sampling data number) were set as more than 4 500 ms and more than 3 000, respectively. The optimal conditions
were determine as follows: τ value (time between 90 degree pulse and 180 degree pulse) of 200 μs, N of 8 and SW value
(receiver bandwidth) of 250 kHz during the test. Good stability and reproducibility could be guaranteed when the sample
was cut into lumps (about 4–5 g), incubated in a water bath at 32 ℃, and subsequently transferred to the probe before the
measurement. These results can provide appropriate detection conditions for applications of LF-NMR for quality assessment
of fresh lean pork and other meats.

Key words: pork, low field-nuclear magnetic resonance, optimal parameters