Microencapsulation of Angelica sinensis essential oil by complex coacervation using chitosan and gelatin: Optimization, characterization, in vitro digestion, and biological activity

Angelica sinensis essential oil (AEO), a valuable flavoring component and potential anticancer agent, possesses a distinctive odor and strong bioactivity. In this study, AEO was encapsulated using complex coacervation of gelatin (Ge) and chitosan (Chi), with the hypothesis that complex coacervation could be used to develop microcapsules capable of protecting AEO from oxidative reactions while regulating volatile compounds released during digestion. The higher encapsulation efficiency (82.68 ± 0.38 %) was achieved, as optimized by Box-Behnken design and a response surface methodology, using a wall-core ratio of 1.50:1, Ge:Chi mixing ratio of 10.38:1, and pH of 5.33. Microencapsulation of AEO permitted rapid initial release of phthalides and monoterpenes, while facilitating progressive liberation of sesquiterpenes with lower volatility. A rapid release of AEO from microcapsules occurred within the initial 120 min under pH conditions simulating gastrointestinal environments.. Furthermore, Angelica sinensis essential oil microcapsules (AEOM) exhibit strong antioxidant activity and bacteriostatic properties, making them effective in protecting essential oil components and enhancing their potential as functional food ingredients.