Interfacial adsorption properties, rheological properties and oxidation kinetics of oleogel-in-water emulsion stabilized by hemp seed protein

An oleogel-in-water (Og/W) emulsion system was constructed by hemp seed protein (HSP) and hemp seed oil oleogel. The effects of different HSP concentrations on the properties of the emulsion system were investigated. It was found that the oil droplets in the Og/W emulsion were spherical particles after being encapsulated by the emulsifier. With increasing HSP concentration, the particle size of the emulsion first decreased and then increased. When the HSP concentration was 3%, the particle size reached a minimum value. At this time, the ζ-potential of the system was −30.8 mV, the adsorbed protein content was 45.05%, the surface tension was 50.49 mN/m, and the roughness was 8.35 nm. Additionally, the apparent viscosity of the emulsion gradually increased with increasing HSP concentration, and the emulsion with 3% HSP had a higher G′, which could better resist the external environmental pressure. Through the exploration of the interfacial adsorption properties, it was shown that increasing the HSP concentration could improve the diffusion, adsorption and molecular rearrangement rate of HSP at the oil-water interface. In addition, the tetrahydrocannabinol retention rate reached 92.86% after 14 days of storage. Finally, the oxidation kinetic model was established, and the equation c=e19.89327e−6940.61627T*t+0.98 was obtained, which could be used to predict the changes in the peroxide value (POV) of hemp seed oil under different storage temperatures and times.