Preparation of pickering emulsion of cinnamon essential oil using soybean protein isolate-chitosan particles as stabilizers

Abstract

This study presents the preparation of cinnamon essential oil Pickering emulsion, aiming to improve the physicochemical properties, water sol ubility, and emulsion stability of cinnamon essential oil. The oil-in-water Pickering emulsion was prepared by ultrasonic emulsification, in which SPICS (soybean protein isolate (SPI)-chitosan (CS) composite granule) was used as the wall material and cinnamon essential oil was used as the core material. The emulsification performance of SPICS was evaluated, and the stability of Pickering emulsion was tested. The results showed that there was hydrogen bonding between SPI and CS, and the tertiary structure of SPI was change, which enhances the hydrophobicity of SPICS surface. When the mass ratio of SPI to CS was 14:1, the emulsification activity of SPICS was 71.92 m2g-1 and its emulsion stability was 106.29%; it also had good dispersibility in water. When the volume of the oil phase was 60%, the encapsulation rate of cinnamon essential oil was 65.23%, the Pickering emulsion did not show obvious delamination for one month; and rheological tests showed the presence of shear thinning, which was judged to be a pseudoplastic fluid. Therefore, SPICS can be used as a wall material to prepare Pickering emulsion of cinnamon essential oil with good stability.