Improving delivery capacity of soy 7S protein via high pressure homogenization: in the case of vitamin D3

Abstract In this work, high pressure homogenization treated soy 7S protein (HPH–7S) was employed as carrier to load and delivery VD3. The encapsulation efficiency (EE) (97.88 %) and bio-accessibility (85.69 %) of VD3 was markedly improved by HPH-7S as compared with that of untreated 7S protein (92.63 %, 73.36 %), while the particle size (80.1 nm) was prominently smaller than that encapsulated by untreated 7S protein (243.3 nm). The photochemical and thermal stability of VD3 in VD3@HPH-7S nanoparticles (VD3@HPH-7S-NPs) was superior to that of VD3 protected by 7S protein. The enhancement of delivery capacity of HPH-7S may be due to the change in protein structure. i.e. the peptide chains of the proteins unfolded during homogenization treatment, exposing more hydrophobic groups and rearranging the tertiary structure, which was verified by Fourier transform infrared, endogenous fluorescence spectrum and surface hydrophobicity.