Preparation and characterization of shrimp shell powder enhanced peach gum/sodium alginate ternary composite films

This study used shrimp shell powder (SSP) as a biomass filler for peach gum/sodium alginate (PG/SA) composite matrix to prepare PG/SA/SSP ternary composite films with enhanced performance. The effects of SSP addition (0-10 wt%) on structure, thermal stability, mechanical behavior, barrier performance, and water susceptibility of the films were investigated. SSP incorporation enhanced the mechanical strength and hydrophobicity of the films through mechanisms such as Ca²⁺ ion cross-linking, hydrogen bonding, and physical filling. At 6 wt% SSP, the film exhibited optimal overall performance: its TS increased by 55%, WVP and OP decreased by about 60% and 67%, along with good UV resistance and thermal stability. Microscopy revealed uniform SSP dispersion, enhancing physical crosslinking density and compactness. Applied to fresh-cut pears, 6% SSP/PG/SA film reduced weight loss to 10.33%, suppressed browning, and delayed TSS and pH fluctuations. This strategy valorizes shrimp shell waste and advances high-performance biodegradable food packaging.