Hydrophobically modified alginate for emulsion of oil in water

Dodecanol was covalently coupled to sodium alginate (NaAlg) via ester functions using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC-HCl) as a coupling reagent to provide an amphiphilic dodecanol alginate (DA) for subsequent use in oil-in-water (O/W) emulsion application. The structure of DA was confirmed by FT-IR spectrometry. The stability of the emulsions prepared with different concentrations (0.3-1.2 wt%) of DA or 1.0 wt% NaAlg was evaluated by measuring droplet size, microstructure, viscosity and creaming. The results showed that the emulsions containing 1.0 wt% NaAlg, 0.3 and 0.5 wt% DA were unstable and the emulsions containing 0.8-1.2 wt% DA presented better stability during storage.