Abstract
Egg yolk powder (EYP), commonly produced by spray-drying liquid egg yolk to facilitate long-term storage and handling, is a stable, concentrated product rich in proteins, lipids, and micronutrients. However, EYP is susceptible to lipid oxidation and loss of functional properties both during processing and storage. This review synthesizes current research on how processing conditions, such as spray drying parameters, oxidation drivers and targeted modifications affect EYP quality. It examines metabolomic profile that revealed compositional changes, evaluates strategies to limit oxidation and discusses both enzymatic and physical treatments designed to improve solubility, emulsification and overall stability. The review also discusses a broad range of food applications in which EYP plays a role. High inlet temperatures during spray drying accelerate lipid oxidation and reduce retention of polyunsaturated fatty acids, while storage temperatures and time further compromise oxidative stability. These conditions drive specific metabolomic shifts increasing oxidized amino acids and lipid hydroperoxides. Volatile compounds and metabolite biomarkers effectively track quality changes under these stresses. Enzymatic hydrolysis and ultrasound treatment enhance emulsification and foam stability by reducing particle size and altering surface hydrophobicity. Such functional advances enable applications ranging from high protein bakery systems, stable oil microcapsules, to 3D food printing and edible films.