Development and application of low-density polyethylene-based multilayer film incorporating potassium permanganate and pumice for avocado preservation

Abstract

This study aimed to develop a low-density polyethylene-based multilayer active packaging film with three layers. The core layer was an active layer containing pumice and potassium permanganate, while the skin layer was the barrier layer impregnated with sodium chloride. The multilayer film showed an ethylene scavenging capacity of 1.6 μmol/(25 in2) within 8 d at 25 °C and was endowed with water absorption capacity. In addition, the oxygen and water vapor permeability of the multilayer film were improved in comparison to the neat one. Further, the multilayer film extended the shelf life of avocado from less than 10 d to 16 d at 25 °C, controlled ethylene and carbon dioxide concentrations, and caused a reduction in the loss of flesh firmness and weight. More importantly, according to migration testing, active agents in the core layer would not migrate to avocado peel, which ensured that avocados would not be contaminated.