Study of chargeability of coating materials and optimization of design and performance parameters of the developed electrostatic spray coating system

Abstract

In this paper, the chargeability of various coating materials has been critically analysed to examine the suitability of the electrostatic spray coating method applicable for coating fruits and vegetables for enhanced shelf life. The design and performance parameters of the electrostatic spray coating system were optimized, and the suitability of the developed technology was studied to evaluate different aspects of food coating applications. The chargeability of laboratory-formulated coating materials, i.e. A (starch), B (polysaccharide), C (protein), D (gums), E (cellulose), and commercially available coating materials, i.e., SS40T+(10%), SS50T+(10%), VMW50+(10%) was examined and the significant charge-to-mass ratio of 2.760, 1.265, 2.593, 2.454, 1.269, 2.104, 4.447, and 2.473 mC/kg was achieved respectively. The charge-to-mass ratio was calculated with respect to an applied high voltage, liquid flow rate, air pressure, conductivity and density of the coating material using an indigenously designed and developed advanced electrostatic spray coating system at a distance of 100 mm from the nozzle tip to Faraday cage. The developed advanced electrostatic spray coating technology has the potential to be used in the food industry, particularly for extending the shelf life of perishable food commodities by enhancing coating efficiency. The experimental results were well aligned with the proposed theoretical considerations.