Curcumin-loaded emulsions stabilized by the succinylated Antarctic krill proteins: Establishment of photodynamic inactivation to preserve salmon

The succinylated Antarctic krill proteins (SAKP) were fabricated using the ultrasound, and the curcumin-loaded emulsions stabilized by SAKP were selected as photosensitizers to construct a photodynamic inactivation (PDI) system to preserve salmon during storage at 4 °C. The SAKP treated with 200 W ultrasound (SAKP-U-200) presented an expanded and flexible structure, a decreased particle size from 465 nm to 358 nm, an increased surface hydrophobicity from 207.1 to 411.5, and its interface absorption capacity was increased by ∼8.0%, which displayed a superior encapsulation and emulsification ability compared with the other succinylated proteins. The emulsions stabilized by SAKP-U-200 efficiently loaded curcumin, and the established PDI mediated by the coating photosensitizers potently inactivated the bacteria in salmon by ∼3.0 Log10 CFU/g (99.9%) after the illumination of 18.72 J/cm2. Meanwhile, the PDI inhibited the changes of color and pH, maintained the integrity of muscle fibers, and reduced the water loss of salmon during the post-treatment storage. Notably, the PDI treatment inhibited the degradation of proteins by ∼7.7%, and decreased the oxidation of unsaturated fatty acids by ∼21%. Therefore, this study expands the application of PDI in preserving the storage quality of aquatic products.