Fish oil-loaded emulsions stabilized by synergetic or competitive adsorption of gelatin and surfactants on oil/water interfaces.

The simultaneous application of proteins and surfactants for emulsion preparation and stabilization is a research hotspot in the field of emulsions, and their interfacial adsorption mechanisms remain unclear. In order to analyze the interaction mechanism of gelatin with low-molecular-weight surfactants, we mainly explored the preparation and storage of fish oil-loaded gelatin/surfactant-stabilized emulsions in this work. The results demonstrated that gelatin and four types of surfactants were synergetically (Span 80 and soybean lecithin) or competitively (Tween 80 and SDS) adsorbed on the oil/water interfaces in the emulsions. The adsorption behaviors affected emulsion stability (creaming, liquid-gel transformation, and droplet coalescence behaviors) and size distribution of emulsion droplets. These fish oil-loaded gelatin/surfactant-stabilized emulsions have the potential to reduce the disadvantages of fish oils and to provide multiple prospective applications in beverages, hard foods, and alkaline foods. It would also be beneficial to the basic understanding of protein/surfactant interfacial adsorption in emulsion formation.