Influence of salting processes on water and lipid dynamics, physicochemical and microstructure of duck egg

Water and lipid changes play important roles for the quality formation of salted duck eggs . In the present study, low-field nuclear magnetic resonance (LF-NMR) and magnetic resonance imaging (MRI) were introduced to monitor water and lipid dynamics of duck egg during salting as nondestructive methods . Four proton pools with different mobilities in fresh duck egg matrix were identified by LF-NMR transverse relaxation, and salting significantly changed the proton mobility due to the gelation of egg yolk, release of lipid and watery of egg white . MRI showed high density of proton with lower mobility and higher mobility in egg yolk and white, respectively, and the brighter region of egg yolk in T 1 images continuously decreased from vitelline membrane to center. The variations in the relaxation parameters and MRI images have a close relationship with other quality characteristics of duck eggs induced by salt. Therefore, LF-NMR and MRI could provide information about water and lipid dynamics of duck eggs during salting, and have great potential for quality assurance in salted duck eggs as a fast and non-destructive method.