Pickering high internal phase emulsions with excellent UV protection property stabilized by Spirulina protein isolate nanoparticles

Herein, we reported the use of natural, renewable, and food-grade Spirulina protein isolate nanoparticles (SPI NPs) as effective particle stabilizers for Pickering high internal phase emulsions (Pickering-HIPEs). SPI NPs were prepared using a straightforward antisolvent technique and characterized using dynamic light scattering (DLS), and zeta potential measurement as well as scanning electron microscopy (SEM). SPI NPs were afterward used as sole stabilizers to prepare the oil-in-water (O/W) HIPEs, the effects of oil content, particle concentration, and pH of aqueous phase on the microstructure, stability, and rheological behaviors of the resulting Pickering-HIPEs were investigated. The Pickering-HIPEs generated showed a self-supporting gel network, a high oil content (up to 85 vol%), and extraordinary storage stability after prolonged storage and UV exposure. Concurrently, the Pickering-HIPEs provided good UV protection for a variety of photosensitive compounds, including fl-carotene, vitamin E, and limonene. These findings would not only advance the development of biocompatible particle stabilizers for Pickering-HIPEs in cosmetic, food, and pharmaceutical industries, but they would also provide a guidance for the protection of photosensitive compounds.