Fabrication and characterization of laurel (laurus nobilis) essential oil nanoemulsion stabilized by sodium caseinate/modified α-cyclodextrin

The direct application of essential oils in food systems faces challenges due to their volatility, strong odor, and instability. This study developed nanoemulsions encapsulating laurel ( Laurus nobilis ) essential oil (LEO) using sodium caseinate (SC) and octenyl succinic anhydride (OSA) modified α-cyclodextrin (α-CD) as composite stabilizers, aiming to enhance emulsion stability and bioactive efficacy. The results demonstrated that a 1:1 SC/OSA-α-CD ratio formed a dense reticular structure with minimal turbidity. NE-S1O1-8 M displayed uniform droplets, the smallest particle size (317.23 nm), and an 86° contact angle. Furthermore, under storage, centrifugation, or heating, NE-S1O1 showed superior stability with negligible changes in particle size or appearance. The encapsulation efficiency, antibacterial and antioxidant activities primarily depended on LEO concentration. The NE-S1O1-8 M emulsion exhibited optimal integrated bioactivity, demonstrating inhibition zones of 18.9 mm against S. putrefaciens and 17.1 mm against S. aureus , along with DPPH and ABTS radical scavenging rates of 79.2 % and 82.8 %, respectively. Although the encapsulation efficiency under this condition was slightly lower than that at 4 × MBC, it remained at a high level above 80 %. This study provides a novel approach for stabilizing active compound-loaded nanoemulsions suitable for food preservation applications.