Antibacterial activity of polyvinyl alcohol (PVA)/ε-polylysine packaging films and the effect on longan fruit
Yana Li, Yuwen Wang, Juying Li
Abstract
Biodegradable and antimicrobial films via combing -polylysine (-PL) and polyvinyl alcohol (PVA) is a promising material for food packaging. We prepared the -PL/ PVA films with the -PL content of 0%, 1%, 3%, 5% and 7% (wt., relative to PVA) by casting method and their physical and chemical properties were characterized. SEM indicated the surface of -PL/PVA films was smooth with well compatibility between -PL and PVA at the -PL addition content of 1%. The tensile strength and barrier properties for water vapor and oxygen of the -PL/PVA films initially elevated and then decreased when -PL content exceeded 1%. The -PL doped endows antibacterial activity of PVA and the antibacterial property of -PL/PVA films was increasing with increase of -PL content. Compared with the control, the -PL/PVA packaging films could inhibit effectively the pericarp browning and pulp breakdown for longan, consequently the rate of commercially acceptable fruit packaged by -PL/PVA films was improved dramatically. However, the effect of -PL/PVA on weight loss rate for longan was worse than the control.