Effect of salting on the water migration, physicochemical and textural characteristics, and microstructure of quail eggs

Abstract

To characterize the process of salting in quail eggs, the effects of different curing times on the physical and chemical properties, texture, and microstructure of the eggs were evaluated using conventional analytical methods. Three different types of protons were found in quail eggs qualitatively analyzed by low-field nuclear magnetic resonance (LF-NMR) and imaging (MRI). With an increase in salting time, the moisture content of the yolks showed a decreasing trend, from 452 to 278 g/kg. The salt content of the egg white increased from 7.2 to 26.9 g/L and from 0.8 to 11.9 g/L in egg yolk. Immersion in NaCl changed the structure of the egg yolk protein and destroyed its thermal stability, as well as increasing oil exudation after heating and the number of granular aggregates in the microstructure of the egg yolk. Scanning electron microscopy (SEM) showed that Na+ induced the aggregation of egg white protein, which destroyed the three-dimensional network structure of the egg white gel, and gradually caused the aggregation of egg yolk protein. Ultimately, this lead to the solidification of the yolk, which changed the shape of the spherical egg yolk particles, resulting in a gritty texture.