Fresh egg yolk was separated into plasma and granules. Then, the egg yolk and its fractions were enzymatically modified with phospholipase A1 (PLA1). Changes in physicochemical and functional properties were investigated. We observed that enzymatic treatment showed a significant impact on the properties of egg yolk and its fractions with regard to emulsifying properties, protein solubility and foaming properties. Meanwhile, the color changes and the microstructure and the thermal behavior of egg yolk, plasma and granules before and after enzymatic treatment were also studied. This study indicated that the existence of lysophospholipids and structural changes in egg yolk granules could be responsible for significant differences in the functional properties of untreated and PLA1‐modified egg yolk, plasma and granules.
PRACTICAL APPLICATIONS
This study aimed to investigate the physicochemical and functional properties of egg yolk, including its fractions (plasma and granules), before and after phospholipase A1 (PLA1) treatment. Such modified egg yolk would have higher protein solubility, thermal stability and emulsifying properties, and present high resistance to extreme temperatures. As these properties of egg yolk powder were improved through PLA1 treatment, the application of PLA1 could make egg yolk have a good practical effect and extend the scope of application.