Abstract:Composite films were prepared by using gelatin，dextran，and different concentrations（0%，0.5%，1.0%，and 1.5%，mass fraction）of active substances（citronellal and α-tocopherol）and characterized by scanning electron microscope，thermogravimetric analysis，and infrared spectra. The effects of different concentrations of active substances on physicochemical，antibacterial，antioxidant，and scallop preservation of composite films were studied.The results indicated that the gelatin and dextran were well-compatible，while the addition of active substances resulted in a rough surface，porous cross-section，and enhanced hydrophobicity of the composite films but did not affect their thermal stability. The thickness，opacity，and antibacterial and antioxidant capacity of the composite films increased with the increase in the concentrations of active substances，while the water vapor permeability and mechanical strength decreased. The composite films containing 1.5% active substances significantly improved the chemical and microbial stability of refrigerated scallops and extended their shelf life by at least six days as indicated by the total viable count. Overall，the developed citronellal-α-tocopherol/gelatin-dextran-based composite films are promising for the preservation of aquatic food products.