Pickering emulsions stabilized by luteolin micro‐nano particles to improve the oxidative stability of pine nut oil

Abstract BACKGROUND Pine oil contains a high percentage of polyunsaturated fatty acids, which make it prone to oxidation. Luteolin (LUT) micro‐nano particles with antioxidant properties can be used as stabilizers to form an edible oil‐in‐water Pickering emulsion to improve the oxidative stability of pine nut oil. RESULTS Under optimal preparation conditions, the LUT micro‐nano particles and pine nut oil account for about 0.44 and 90.9 g·kg −1 of the total mass of the emulsion, respectively. The LUT particles in the suspension have a mean particle size of about 479 nm, present a sheet‐like structure with a cut surface of 30–50 nm, and can reduce the surface tension of deionized water. In the optimized Pickering emulsion, the emulsion droplets are approximately spherical and have a mean diameter of about 125.6 nm and uniform distribution. The optimized Pickering emulsion droplets can remain stable for up to 2 h in an environment where the pH levels are 7–8.5, ultraviolet B radiation (UVB) irradiation, of less than 5.0 g·kg −1 , and at a temperature of 80 °C. The stability of the emulsion in simulated digestive fluid changed minimally. In the first 7 days of the accelerated oxidation experiment, LUT micro‐nano particles not only successfully protected the integrity of emulsion droplets but also fully inhibited the peroxidation of pine oil. CONCLUSION The strong antioxidant properties of LUT micro‐nano particles, and the dense protective layer they formed, stabilized the Pickering emulsion successfully. The particles also improved the oxidation stability of pine nut oil. © 2020 Society of Chemical Industry