Differential mechanisms of saccharides in mitigating heat-induced aggregation of liquid egg yolk: a comparative study on rheological, functional, and structural properties

The quality deterioration of liquid egg yolks caused by increased sterilization temperature was alleviated. This study investigated the effects of sucrose, glucose, trehalose, and arabinose on the heat aggregation behavior of egg yolks. The results showed that after heat treatment, saccharides significantly increased the thermal denaturation temperature, effectively inhibited heat-induced thickening, and slowed the decrease in soluble protein content and emulsifying activity of the liquid egg yolk. Moreover, the Fourier transform infrared spectrometry and surface hydrophobicity data indicated that saccharides could alleviate the changes in the degree of structuration and the exposure of hydrophobic residues to egg yolk protein molecules. It was also found that the aggregation degree of sugared egg yolks was relatively low according to the microstructure and particle size. In summary, sucrose, glucose, trehalose, and arabinose could alleviate the heat aggregation behavior of egg yolks and could be applied to produce liquid egg yolks with enhanced heat stability.