Preparation, characterization and control release properties of Citrus medica L. essential oil-loaded particles

Microencapsulation is the most common technique that has been utilized to increase the stability of bioactive compounds. This study aimed to evaluate the potential of whey protein isolate (WPI) in the microencapsulation of Citrus medica essential oil (CEO) by ultrasonication method.

The influences of core-coating ratio (10-100%) and ultrasonication power (50-150W) on the physicochemical properties of microcapsules were evaluated. 

Particle diameter of the microparticles increased by increasing the core-coating ratio. PDI value increased and decreased with the increase of core ratio. The highest encapsulation efficiency (EE) (84.8%) belonged to CEO loaded microcapsule with values of US power and core-coating ratio equal 100.  Mathematical modeling indicated that the type of release from microcapsule containing CEO in different simulating conditions was fake release and a combination of fake/complex release. SEM results confirmed a spherical shape-like structure. The formation of new interactions between WPI and CEO was confirmed by FT-IR analysis. 

The results showed that the encapsulation of Citrus medica L. essential oil by biopolymers can be successful.