Study on the stability of sodium alginate modified zein/adzuki bean seed coat polyphenol composite nanoparticles and the loading of curcumin in emulsion

Curcumin, a bioactive compound characterized by its limited solubility in water and low bioaccessibility, which requires an effective delivery system to enhance stability and absorption. This research focused on creating Pickering emulsions stabilized by zein-adzuki bean seed coat polyphenol-sodium alginate composite nanoparticles (ZAS) to improve curcumin delivery. The effects of different concentrations of sodium alginate (SA) on the properties of ZAS were investigated. Fourier transform infrared spectroscopy (FTIR) showed that there were hydrophobic and hydrogen bonds interactions between SA and nanoparticles, and Differential Scanning Calorimetry demonstrated an improvement in thermal stability. Accelerated oxidation experiments showed that ZAS stabilized Pickering emulsions had good anti-oxidant capacity. In comparison to the control group, the addition of SA increased the loading rate of curcumin to 81.65 ± 1.56 % with improved bioaccessibility (27.99 ± 0.26 %) and in vitro digestion stability (55.72 ± 0.22 %). The findings indicate that ZAS nanoparticles modified with SA markedly enhance the stability of Pickering emulsions, while also attaining a high loading efficiency of 81.65 % and bioaccessibility of 27.99 %. This suggests their potential utility in functional food applications.