High ethanol tolerance of oil-in-water Pickering emulsions stabilized by protein nanoparticles

Abstract

A high ethanol tolerance of oil in water (O/W) Pickering emulsion solely stabilized by pumpkin seed protein isolates (PSPI) nanoparticles was formed at their isoelectric point (pI). It is noting that the volume ratio of ethanol to emulsion can reach to 90%, which is the highest value for O/W emulsion reported so far. Furthermore, the emulsion containing 90 vol% ethanol could remain stable at room temperature for 60 days, demonstrating good storage stability. After vitamin E (VE) was encapsulated as an active ingredient, the ethanol tolerability of the produced emulsion can remain unchanged. The high stability of O/W Pickering emulsion at such a high ethanol ratio was possibly due to the full coverage of PSPI nanoparticles at the interface. It is a unique and straightforward method for obtaining a stable and biocompatible O/W Pickering emulsion with excellent ethanol tolerance. Considering the protein used is food-grade and renewable, this emulsion could have a wide range of applications in the field of functional food and cosmetics.