Scilight Press

Edible coating is in a form of thin layer on the fruit surface, which delays the senescence of fruit materials by forming semi-permeable barrier for permeation of gases and moisture. The thickness and uniformity of coating on fruits play crucial role on permeability of the coating solution. Based on these backgrounds electrostatic spray coating machine was developed and it consisted of high voltage generator and electrostatic spray coating section. Developed electrostatic sprayer section involved electrostatic spray (twin fluid) nozzle with high voltage power supplying unit (1 kV to 5 kV), liquid discharge (10 to 30 ml/min) and pressurized air (2.5 and 4 kg/cm2 ) from the air compressor. The maximum value of charge to mass ratio (CMR) obtained at 4 kg/cm2 pressurized air flow rate was 1.70 mC/kg at 5.0 kV applied voltage under10 ml/min of spray liquid discharge rate.