Inhibition of Pectobacterium carotovorum-mediated potato soft rot by carboxymethyl cellulose-based antibacterial edible coating containing green tea extract

This study was conducted to propose a new strategy for preventing Pectobacterium carotovorum-mediated potato soft rot through the development of a carboxymethyl cellulose (CMC)-based antibacterial coating incorporated with green tea extract (GTE). GTE/CMC films resulted in increased water vapor permeability due to the incorporation of polar groups in GTE. In the antibacterial test against P. carotovorum, the MBC value of GTE was 2 mg/mL. The time-kill assay demonstrated that GTE/CMC (2 × MBC) completely eradicated bacteria within 0.5 h (~6.4 log CFU/mL reduction). The potential of GTE/CMC to prevent potato soft rot was evaluated by monitoring the potato appearance, maceration area, and texture properties. The GTE/CMC-coated potatoes exhibited significantly reduced maceration area and remained firm for 3 days. Moreover, there was no change in the antimicrobial efficacy for 8 weeks. The developed GTE/CMC could be used as a biological coating system for postharvest storage and soft rot prevention.