Gel properties and microstructure of Nemipterus virgatus myofibrillar protein/konjac glucomannan emulsion gel: effects of fish oil content.

BACKGROUND: Emulsion gels exhibit promising application prospects as solid fat substitutes and carriers for lipophilic bioactive compounds. This work investigated the effects of oil concentrations (40-65%, v/v) on the interfacial adsorption in emulsions, rheological properties, gel characteristics, and microstructure of emulsion gels stabilized by a mixture of Nemipterus virgatus myofibrillar protein (MP) and konjac glucomannan (KGM). RESULTS: The emulsifying activity of the MP/KGM mixture, the interfacial protein adsorption in the MP/KGM emulsion, and emulsion viscosity all peaked at an oil concentration of 55%. The increase in oil content (particularly 55%) assisted the structural transformation in MP from α-helix into β-sheet, promoting the development of a denser, more uniform network structure, which ultimately enhanced the hardness, gel strength, water-holding capacity, elasticity, and deformation resistance of emulsion gels. However, at excessively high oil levels (>55%), the MP/KGM mixture became inadequate to cover the oil-water interfaces, resulting in deterioration in the performances of the emulsion and emulsion gel. CONCLUSION: The MP/KGM emulsion gel with 55% fish oil displayed optimal gel performance. This study offers practical foundations for developing stable emulsion gels based on aquatic proteins. © 2026 Society of Chemical Industry.