Valorization of saline byproducts: Development of composite films from waste salted egg white and plant extracts

This study used salted egg white (SEW) as the matrix and added different plant extracts to prepare SEW composite films and explored their application in banana preservation. The results showed that SEW had certain antibacterial properties and excellent soil degradability (degradation rate > 90% within 4 days). The addition of plant extracts significantly improved the hydrophobicity and mechanical properties of the films. In addition, the composite films had a transmission rate close to 0% for the UV-B and UV-C bands (280 and 330 nm), demonstrating excellent UV shielding performance. In terms of antioxidant and antibacterial properties, the film modified with Eucommia ulmoides extract performed the best. The banana preservation experiment further indicated that the SEW composite films could extend the shelf life of bananas by 4 days and effectively maintain fruit quality. In conclusion, SEW composite films have broad application prospects in the field of active food packaging.