Enhancement of structural and emulsifying properties of omega-3 enriched surimi gel using egg yolk and salmon by-product oil

This study aimed to optimize an n-3-enriched emulsion surimi gel using salmon by-product oil and egg yolk as natural emulsifiers. The maximum emulsification capacity of Alaska pollock surimi reached up to 1.8 times the myofibrillar protein content, and the optimized formulation (20% fish oil and 75% egg yolk, w/w) achieved 2000 mg of omega-3 per 100 g of gel. Egg yolk enhanced disulfide and hydrophobic interactions within the surimi gel, promoting a firmer gel network with increased β-structure formation in proteins. Surimi gels containing egg yolk showed increased hardness and springiness. Increasing the egg-yolk content significantly improved emulsion stability (11.75min to 24.77 min), surface hydrophobicity (21.82 μL to 29.67 μL) by up to 30%, and water-holding capacity (89.57 to 96.37%). The addition of egg yolk also stabilized oil droplets in the emulsion gel, effectively filling cavities in the 3D network and reinforcing the gel structure. These findings provide valuable insights into the structural stabilization of surimi-based emulsions and support the valorization of marine by-products in the development of functional foods. • Omega-3-enriched surimi emulsions are stabilized by egg yolk, a natural emulsifier • In optimal condition (20% fish oil, 75% egg yolk), 2,000 mg n-3/100 g was provided • Egg yolk enhanced disulfide and hydrophobic interactions, reinforcing the gel • Structural changes increased β-sheet content and enhanced the protein gel network • Egg yolk addition improved texture quality, WHC, and overall emulsion stability