Active chitosan/alginate/C-CNF absorbent pads with grapefruit essential oil microcapsules for hairtail (Trichiurus haumela) preservation.

An active water-absorbing preservation pad was fabricated by incorporating grapefruit essential oil microcapsules (GEOMs; 0-2 MIC) into a chitosan/sodium alginate/carboxylated cellulose nanofiber (CS/SA/C-CNF) matrix to control drip loss and preserve chilled hairtail (Trichiurus haumela). Structural, physicochemical, and bioactive properties were characterized. SEM and FTIR verified a stable CS/SA/C-CNF network with physically embedded GEOMs, and TGA showed no loss of thermal stability after GEOM incorporation. With increasing GEOM loading, pad thickness rose from 3.72 to 4.66 mm and hardness decreased from 255.69 to 115.37 g, whereas springiness changed little. GEOMs enhanced antioxidant capacity and antimicrobial activity, particularly against Escherichia coli. In hairtail stored at 4 °C, the 2 MIC pad reduced drip loss, delayed quality deterioration, and kept TVB-N below the specified limit through day 8. Overall, GEOM-loaded CS/SA/C-CNF pads integrate absorption with active protection and are promising bio-based packaging for seafood and other highly perishable aquatic products.