Low-Field Nuclear Magnetic Resonance of Proton (¹H LF NMR) Relaxometry for Monitoring the Time and Temperature History of Frozen Hake (Merluccius merluccius L.) Muscle

Abstract

© 2015, Springer Science+Business Media New York. The objective of the work was to investigate the potential of low-field nuclear magnetic resonance of protons (¹H LF NMR) relaxometry to produce indicators useful in the estimation of the quality and shelf life of frozen hake (Merluccius merluccius L.) muscle as affected by storage temperature and time. ¹H low-field NMR T<inf>2</inf> transverse relaxation measurements were performed from fillets of a total of 145 hakes that had been stored at −10, −20, −30, or −80 °C for up to 150 weeks. The principal component (PC) scores from the ¹H LF NMR distribution of T<inf>2</inf> relaxation times were adjusted to zero-order kinetics and the reaction rates followed an Arrhenius-type pattern. Kinetic modeling using the PC scores of the 12–400-ms range resulted in the best model corresponding to both T<inf>21</inf> and T<inf>22</inf> regions. The temperature dependency of the rate of reactions, measured by B values, was similar to that previously found for shear resistance and for the hydrolysis of phospholipids, well-known markers related to the sensory quality in this species. Thus, our results suggest that this methodology has a great potential to evaluate the frozen storage time and temperature in hake as well as to provide an indication of the expected quality of the fillet.