Development of a Single-Sided Nuclear Magnetic Resonance Scanner for the In Vivo Quantification of Live Cattle Marbling

Abstract

Non-invasive in vivo marbling quantification helps owners to choose the optimum nutritional management for growing cattle and buyers to more precisely evaluate grown cattle at auctions. When using time-domain proton nuclear magnetic resonance (NMR) relaxometry, it is possible to quantify muscle and fat separately by taking advantage of the difference in the spin–spin relaxation time (T2) between water molecules in muscles and fat molecules, which would contribute to the non-invasive and objective determination of marbling scores. With this in mind, we developed a prototype NMR scanner (4.1 MHz for protons) using an original single-sided magnetic circuit and a plane radio frequency (RF) coil for use in the non-invasive quantification of water and fat in live cattle. The sensed region of the developed scanner is compact and almost cubical (19 × 19 × 16 mm3) while the investigation depth (the distance from the RF coil to the center of the sensed region) has been lengthened to 30 mm, which is sufficient for the in vivo trapezius muscle measurement of live cattle. Measurements of 17 samples of beef meat blocks kept at 39 °C were taken in a laboratory to successfully obtain the calibration lines used to convert the NMR signals into water and fat weight fractions at correlation coefficients in excess of 0.9. We also showed that each meat sample could be measured in about 10 s with a measurement error as small as approximately 10 wt%. Accordingly, we believe that our prototype scanner would be useful for in vivo marbling measurements of live cattle trapezius muscles.Electronic supplementary materialThe online version of this article (doi:10.1007/s00723-015-0657-4) contains supplementary material, which is available to authorized users.

Nondestructive quantification of moisture in powdered low-rank coal by a unilateral nuclear magnetic resonance scanner

“…(1) monotonically increases with increasing thickness of the stacked rubber. According to Nakashima (2015), thresholds of 10 and 90% were applied to the normalized M 0 values in Fig. 2 and ESM1cd.…”

“…(i) The CPMG data acquisition time for a sample was 128 s in the present study, which should be shortened for practical real-time monitoring. It would be possible to reduce the acquisition time to several seconds if the sensor unit is equipped with a RF noise shield cloth (Nakashima 2015). Enlargement of the sensed region by careful design of the magnetic circuit (Marble et al 2007) to increase the signal intensity could be another possible solution.…”

“…Thus, an NMR measurement time of 128 s (0.5 s × 256 times) was required for each coal sample. No RF shield cloth (Nakashima 2015(Nakashima , 2019 was used to reduce the environmental RF noise during NMR measurements at the laboratory.…”

“…ESM1a. The details of the experimental method using silicon rubber sheets are described elsewhere (Nakashima 2015). (ii) One of the drawbacks of the unilateral magnetic circuit is the low S/N ratio compared with a conventional bilateral magnet (Anferova et al 2004).…”

NMR mit Tischgeräten und deren Anwendungen von der Materialwissenschaft bis zur organischen Chemie

“…Zentralfeldmagnete werden auch zur Untersuchung von lebenden Pflanzen in der Natur und Gewächshäusern sowie von Erntequalität genutzt, wohingegen Streufeldmagnete vielversprechend im Hinblick auf die Charakterisierung von Zustand und Funktion von oberflächennahem biologischen Gewebe wie Haut und Sehnen sind, wobei das kompakte, mobile Design von großem Vorteil ist . Streufeldmagnete wurden ebenfalls für die Untersuchung von verpackten Lebensmitteln sowie vom Fettgehalt im Fleisch lebender Tiere erprobt …”