Characterization and preparation of Litsea cubeba essential oil microcapsules encapsulated by modified maltodextrin prepared under the guidance of dynamic changes in protein structure

This study systematically examined the dynamic changes of aggregation and unfolding of whey protein isolate (WPI), determining optimal conditions of 80 °C, 80 min. Based upon these findings, WPI-maltodextrin (WPI-MD) conjugates were synthesized. FT-IR results revealed that a new peak (CN) appeared at 1545 cm^-1, which indicating covalent binding between WPI and MD. Notably, the WPI-MD conjugates exhibited enhanced functional attributes. Furthermore, this conjugate was used as the wall material to prepare LCEO microcapsule. The results showed that the microcapsules based on WPI-MD conjugates outperformed pure MD in encapsulation efficiency (EE), microstructure, antibacterial and antioxidant properties. In addition, the sustained-release behavior study in the food model showed that the microcapsules could effectively slow down the release of the core material, showing excellent controlled release performance. In summary, controlled wet-heat Maillard glycosylation successfully produced WPI-MD conjugates, enabling microcapsules with high EE, functional activity, and sustained release, supporting food industry applications as functional carriers.