High-quality Antarctic krill oil OSA starch microcapsules prepared by multi-scale immobilized enzyme nanoflowers with selective catalytic activity

In this work, an α-amylase-inorganic hybrid catalyst with a multi-scale flower-like structure is designed and applied for the selective pre-treatment of starch to produce high-quality Antarctic krill oil octenyl succinic anhydride (OSA) modified starch microcapsules. Unlike the conventional free enzyme pretreatment hydrolysis process, which randomly disrupts the starch structure, the α-amylase-inorganic hybrid nanoflower catalyst can selectively hydrolyze branched-chain starch, thereby exposing more concentrated reaction sites for subsequent esterification reaction. The resulting OSA-modified starch exhibits excellent emulsification and encapsulation properties, and the resultant Pickering emulsion demonstrates effective protection of the embedded active substances and Antarctic krill oil. After 15 days of storage, the particle size remains essentially unchanged. This work is expected to contribute to the development of a novel starch-based emulsifier for use in the food and pharmaceutical industries.