Investigating the effect of nanoparticle concentration and oil content on the physical stability of Pickering emulsion stabilized by chitosan nanoparticles

Recently, the preparation of Pickering emulsion has attracted particular attention due to its wide range of applications in various industries, including the food and pharmaceutical industries. The present study aimed to prepare a Pickering emulsion stabilized with Chitosan nanoparticles (CSNPs) and investigate the effect of nanoparticle concentration and oil content on physical stability. First, the nanoparticles were prepared by the ionic gelation technique. Then, morphology, particle size distribution, wettability, Fourier-transform infrared (FTIR) spectra of nanoparticles were determined. FSEM results revealed that the nanoparticles are predominantly spherical, with an average size of 69 ±1nm. Also, the results of the FTIR spectrum analysis and wettability confirmed the formation of nanoparticles. In the second stage, emulsions were prepared at different concentrations of CSNPs (0.45, 0.6, and 0.75% w/v) and the ratio of oil to the aqueous phase (10, 20, and 30%). The results revealed that nanoparticle concentration and oil content had a significant effect on emulsion physical stability. In a fixed oil volume fraction, physical stability increases with the increase of nanoparticles' concentration. In contrast, the oil content showed different effects on the properties of emulsions prepared with different concentrations of nanoparticles.