Effect of Ozone on Prolonging the Shelf Life of Mango and Broccoli During Cold Storage and Distribution

Abstract

A number of ozone technology systems have been claimed to remove the ethylene gas released from horticultural produce and airborne pathogens in storage environment. However, contradictory results were reported in the literature. This study was aimed to determine the effect of ozone technology system in removing the ethylene gas in the storage atmosphere for extending shelf life of mango and broccoli. The experiment was carried out in two similar cold rooms (10.68 m3) with and without (control) the ozone technology system. The experiments were conducted separately for mango and broccoli, which are a medium producing and sensitive and a very low producing but high sensitive to ethylene commodities, respectively. Mixed loads of fruits and vegetables were also tested representing the common practice during storage and distribution. Regular slotted containers and reusable plastic containers were compared. Ethylene gases (15 ppm) were introduced in the cold rooms. Samples were kept at their optimum temperatures. Changes in respiration and ethylene production rates, total soluble solid (TSS), titratable acidity (TA), firmness, L*, a*, b* color and weight loss were determined during storage. In mango, TSS/TA in the control group showed a slight increase after 7 days. In broccoli, yellowing after 7 days was apparent to the samples stored in both cold rooms (with or without ozone). No significant (p > 0.05) differences in weight loss, respiration rate and ethylene production rate were observed for both mango and broccoli. Similar trends were shown for mixed loads. Corrugated and reusable containers showed no significant (p > 0.05) differences in terms of produce quality. In our cases, ozone technology system did not seem to effectively eliminate the ethylene in a cold room nor prolong the shelf life of mango, broccoli and mixed loads.