Schiff base crosslinking based dialdehyde-chitosan/gelatin/tea polyphenol electrospun nanofibrous membranes with excellent antibacterial and antioxidant activity for food packaging

Chitosan and gelatin (GEL) are the two most common substrates for green active food packaging. However, chitosan is difficult to solute in water, and gelatin-based films are limited in application by gelatin’s poor active and basic properties. In this work, chitosan was modified to dialdehyde-chitosan (DCS), then it was blended with gelatin and doped with tea polyphenol (TP). Finally, the above materials were electrospined and Schiff-base crosslinked to dialdehyde-chitosan/gelatin/tea polyphenol nanofibrous membranes (DCS/GEL/TP-M) with antibacterial and antioxidant properties and good basic properties. The crosslinking process greatly enhanced the basic properties of the membranes, the addition of TP improved the activity of the membranes, with the inhibition of E. coli and S. aureus up to 91.08 % and 89.31 %, respectively, the scavenging of 1,1-diphenyl-2-picryl-hydrazyl radical (DPPH) free radicals of 85.43 %, and practical preservation experiments showed that the prepared film successfully extended the shelf life of strawberries to 7 days at 25 ℃. The results show that the DCS/GEL/TP-M have good application prospects in active food packaging.