Effect of Post-harvest Ozone Fumigation on Storage of Onion

The storage of commercial onions is essential to meet off-season demands; however, it often results in significant quality degradation and post-harvest losses, including physiological loss in weight, sprouting and rotting. Thus an attempt had been made to test efficacy of ozone fumigation on physical and quality attributes of onion cv. Nasik Red. Onions were fumigated with varying concentrations of ozone in airtight LDPE (Low Density Poly Ethylene) containers for specific duration followed by 2 hours exposure to atmospheric air to dissipate residual ozone. The treated onions were stored and examined for about 3 months. Among treatments, the onions treated with a lesser ozone concentration (3637.2µl L-1 ozone per 10 minutes) demonstrated superior results including significant reduction in physiological loss in weight, sprouting, rotting, black mold incidence with the highest percentage of marketable bulbs. These findings suggest that controlled ozone fumigation, particularly at lower concentration effectively preserve the onions quality during storage, offering promising post harvest management strategy.