Acta Scientiarum Polonorum Technologia Alimentaria

Background. Polysaccharides are attractive materials for various applications due to their non-toxicity, wide availability, biocompatibility, biodegradability, and ease of chemical modification. In the food, cosmetic, and pharmaceutical industries, they serve as natural emulsifiers and stabilizers, preventing creaming and droplet flocculation in emulsions. Alginate, a widely recognized stabilizer, can be modified for use in oil-in-water (o/w) emulsions; however, the effects of emulsion conditions on the performance of modified alginate require further investigation. This study investigates how alginate modification, emulsion pH, and storage temperature affect emulsion stability, kinetics, viscosity, droplet size, emulsifying activity index (EAI), and emulsifying stability index (ESI).
Material and methods. Alginate was modified with dodecenyl succinic anhydride (DSA) at 30°C with continuous stirring for 150 minutes. Emulsions were prepared with alginate-to-fish oil ratios of 1:2 and 2:1 (w/w), at pH levels of 4, 6, and 8, and stored at 30°C and 40°C. Emulsion stability, viscosity, droplet size, EAI, and ESI were systematically characterized.
Results. The modification successfully increased alginate’s hydrophobicity, achieving a degree of substitu­tion (DS) of 0.1407. Modified alginate-stabilized fish oil emulsions, maintaining up to 10% stability after 300 minutes of storage at 30°C, using a 2:1 alginate-to-oil ratio at pH 8. Phase separation followed zero-order kinetics (R² = 0.9630). Higher emulsifier concentrations and pH enhanced viscosity, EAI, and ESI, while reducing droplet size. Increasing storage temperature negatively affected the emulsion stability.
Conclusion. The stability of fish oil emulsions stabilized with modified alginate is significantly influenced by emulsifier concentration, pH, and storage temperature. Modeling emulsion instability offers a valuable tool for optimizing formulation parameters. Future research should focus on enhancing emulsification efficiency to promote the sustainable use of alginate in fish oil fortification.