Black bean protein isolate-gum Arabic coacervated citronellal microcapsules: Preparation, characterization, antibacterial activities, and application in strawberry preservation

Black bean protein isolate-gum Arabic (BBPI-GA) coacervates were employed for citronellal encapsulation, and the feasibility of citronellal-loaded microcapsules for strawberry preservation was investigated. The optimal BBPI-to-GA ratio and pH value for fabricating BBPI-GA coacervates were 4:1 and 4.1, with hydrogen bonding and electrostatic interactions serving as two primary drivers for complex coacervation. The characteristic core-shell morphology of the prepared wet microcapsules and the intact surface of the freeze-dried microcapsules indicated the successful encapsulation of citronellal in coacervates, with a high encapsulation efficiency (EE) of 82.95 ± 0.37%. The prepared citronellal microcapsules displayed a uniform particle size distribution, with an average size of 25.63 ± 2.69 μm. The encapsulated citronellal displayed improved thermal and storage stability, sustained release property, and stronger antimicrobial activity than free citronellal. Furthermore, compared with free citronellal, microencapsulated citronellal more effectively inhibited spoilage microorganisms, mitigated weight loss, and retarded firmness degradation in stored strawberries, verifying its great potential for fruit preservation.