The present work focusses on developing edible antibacterial coatings to enhance shelf life and improve the postharvest quality of banana fruit. In the first part of the work, coatings were formulated by gum-based aqueous solutions using plasticizer. The antibacterial property in the gum solution was imparted by the addition of chitosan (CH) solution. The fruits were coated with gum-CH layer, and the delay in ripening was examined. The formulated coating solutions on the banana fruit showed a significant decrease in the ripening rate than the control (without coating) fruits, which were stored at selected conditions. The results showed that the formulated samples have the ability to enhance the shelf life of the banana fruit remarkably. In another part of the work, coatings were prepared by incorporating silver (Ag) in the form of quantum clusters (QCs) in the gum-based matrix to impart antibacterial properties to the edible coating. The QCs are particles smaller than nanoparticles, which range from a few atoms to few tens of atoms in size. These AgQCs are preferred over nanoparticles as they further reduce the quantity of metallic content and are non-toxic to human cells. QCs were synthesized of conjugating AgQCs with the gum. This approach provides an effective route to reduce metallic content and simultaneously imparts antibacterial property. On conjugation, gum-AgQCs have the potential as an edible antibacterial coating. The successful cluster formation in the gum solution was confirmed by high resolution transmission electron microscopy (HR-TEM). The developed gum-AgQCs are expected to have great potential to enhance the postharvest shelf life of fruits and vegetables as coatings by providing antibacterial properties.