Integrated Proteomic and Characterization Analyses Revealed the Different Colors of Edible Bird's Nest

Edible bird's nest (EBN) is considered to moisten the lung and nourish yin in China. EBN from different geographical sources vary in morphology, material composition and commercial value. In this study, EBN samples with four different colors were collected, and their protein compositions were analyzed by proteomics technology. Combined with characterization analysis, the physicochemical properties and material composition were analyzed, including physical morphology, protein composition, and metal element composition. Proteomic analysis initially identified 73 differential peptide sequences, of which 59 showed significant abundance differences (p < 0.05). After removing redundant peptide assignments, these sequences corresponded to 51 non-redundant proteins exhibiting significant abundance changes among the four EBN color groups. Among them, the beige edible bird's nest (BEBN) contained a large number of amino acids with iron-chelating ability, which was consistent with its high Fe content. Gene Ontology (GO) analysis revealed that the functions of the differential proteins in EBN were mainly related to glycoprotein hydrolysis. In conclusion, this study elucidated different expressed proteins and their potential functions in EBN with various colors, which provided a basis for production standardization and processing advances in EBN industry.