Olive leaf extract (OLE), as a natural antioxidant, was encapsulated within nanostructured lipid carrier (OLE-NLC) and the physico-chemical, microstructure, physical stability, antioxidant activity, and encapsulation efficiency (EE%) were evaluated. Then, it was loaded into the pectin-sodium caseinate hydrogel network and its antioxidant and physicochemical properties were examined during storage. The particle size, polydispersity index (PDI), and zeta-potential (lambda) of the OLE-NLC nanoparticles and OLE-NLC containing hydrogel were 112.9 and 303 nm, similar to 0.34 and 0.58, respectively. Spherical particles with flat surface were observed by scanning electron microscopy (SEM) for both systems. During 40 days of storage at 4 degrees C, the NLC particle size was stable and remained <100 nm. The Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) results showed that OLE was loaded physically in both systems considering the formation of new hydrogen bonds and amorphous structure of both systems. Rheological studies showed the Newtonian behavior of the hydrogel (dilute The retention of antioxidant activity was higher in OLE-NLC containing hydrogel for 30 days. Overall, OLE-NLC containing hydrogel could be suitable for OLE encapsulation to maintain its antioxidant properties against environmental factors and also could be considered in high-fat foods to reduce oxidation and enhance their nutritional properties.
NSTL
Elsevier
