The chicken egg and foods containing egg components are an important part of human nutrition. Furthermore, eggs are a potential source of bioactive molecules and a potential delivery system for therapeutic proteins, explaining the continuing scientific interest in eggs and their components. Using mass spectrometry-based high-throughput proteomic techniques, 119 proteins in egg yolk, 78 proteins in egg white, and 528 proteins in the decalcified eggshell organic matrix have recently been identified. Most of these proteins were identified in their respective egg compartment for the first time. Some of these proteins were already known from chicken tissues or other egg compartments, but many were novel. In the eggshell soluble matrix 39 phosphoproteins containing more than 150 different phosphorylation sites were identified. Twenty-two of the identified phosphoproteins had not been recognized as phosphoproteins previously.
