Characterization of multi-functional, biodegradable sodium metabisulfite-incorporated films based on polycarprolactone for active food packaging applications

Abstract

Consumer demand warrants improved efficacy and environmental impact of food packaging modalities. Here, multifunctional biodegradable films were prepared using 10, 20, and 40 wt% sodium metabisulfite (SM) as an active compound along with polycaprolactone (PCL). Increased SM content significantly affected film oxygen scavenging, antioxidant, anti-browning, and antimicrobial properties (p < 0.05). The %inhibition of ABTS and DPPH radicals increased from 75.8 % and 7.4% to 99.9% and 25.3 %, respectively, with the SM concentration increasing from 10 to 40 wt%. Additionally, SM/PCL films decreased the browning index from 35.52 to 19.70. SM/PCL films were effective against both Staphylococcus aureus and Escherichia coli and inhibited fungal growth. Our findings further suggest that SM/PCL films significantly reduce the amount of packaged oxygen under the conditions expected in foods (e.g., high humidity and temperature). Thus, SM/PCL films exhibit good potential for the development of active food packaging to prolong food product shelf life.