Abstract:Perilla oil is a natural nutraceutical that can be used as a food supplement and pharmaceutical preparation. Perilla oil is insoluble in water, and it is quite difficult to incorporate it into an aqueous medium, resulting in lower bioavailability. In this study, the HLB value based on surfactant was proposed to guide the preparation of composite surfactant,and combined with a pseudo-ternary phase diagram, the nano-emulsion was prepared by the method of inversion emulsification. The main objective was to optimize the process parameters to form a stable perilla oil nano-emulsion and evaluate its stability. The optimal formula of perilla oil nano-microemulsion was as follows: When the HLB value of Tween80/Span20 was 13, the mass ratio of the compound surfactant and the total oil phase (IPM ∶ perilla oil = 3 ∶ 2) was 8 ∶ 2; when the HLB value of the Tween80/Span20 compound was 14, the mass ratio of the compound surfactant to the total oil phase(IPM ∶ perilla oil = 1 ∶ 1) was 8 ∶ 2; when the HLB value of the EL-40/PEG-400 compound was 13.5, the mass ratio of the compound surfactant to the total oil phase (IPM ∶ perilla oil = 2 ∶ 1) was 7.5 ∶ 1. The particle size, potential and type of the prepared perilla oil microemulsion were analyzed, and the particle size of the stable perilla oil nano-emulsion was mainly distributed at 53.10~69.16 nm, and the potential distribution was -32~-34.6 mV, which further proved that the stability of perilla oil microemulsion was good, and all prepared microemulsion were oil-in-water type. The prepared perilla oil nano-microemulsion was placed in an oven at 37 ℃ for 15 days, and the prepared perilla oil nano-microemulsion had better oxidation stability than the perilla oil.