LAUSR

BACKGROUND In this study, low-field nuclear magnetic resonance (LF-NMR) and magnetic resonance imaging (MRI) were used to investigated the moisture migration of beef during refrigeration storage, and its relationships to some physicochemical quality indicators were analyzed using partial least squares regression (PLSR). RESULTS There were three water components ascribed to bound water, immobilized water and free water in beef matrix revealed by low-field nuclear magnetic resonance (LF-NMR) relaxation results. The transverse relaxation time and peak area of immobilized water declined as the proceeding of storage due to the disrupt in microstructure revealed by scanning electron microscope images. MRI images found obvious water migration of beef during refrigeration storage, and scanning electron microscopy images revealed that the integrity of the muscle fiber bundle was destroyed. In addition, the increase of storage time also lead to increase of pH, total volatile basic nitrogen, TBARS value, weight loss, cooking loss and b* value, and decrease of WHC, L* and a* values, and textural properties. CONCLUSION The strong correlations between water migration and the physicochemical quality changes suggested the possibility of LF-NMR as a rapid and noninvasive method to evaluate beef quality. This article is protected by copyright. All rights reserved.