Ozone as a postharvest treatment to maintain the quality characteristics of fresh-cut plants

Consumer’s awareness of the health benefits of fresh fruits and vegetables consumption has urge the need to effective and proper methods to increase the quality, safety and postharvest life of minimally processed fresh products. In this concern, gaseous ozone has several distinctive features, making it suitable for food application. This work aimed to investigate the effect of ozone treatment on physical, chemical and biological quality of some fresh-cut plants. Plant quality was determined by means of weight loss, color, phytochemical, volatile components and microbiological indexes. The obtained results showed that ozone treatment at the concentration of 25 ppm for 20 min effectively decreased the weight loss of plants with insignificant (p > 0.05) effects on the color parameters. Furthermore, ozone treatment increased the phenolic contents and antioxidant activity of the tested plants. Ozone treatment decreased the concentration of 8, 7 and 6 compounds in the essential oil celery, coriander and parsley, respectively. In contrast, it increased the concentration of 3, 10 and 6 compounds and led to the formation of 5, 4 and 5 new compounds in these oils, respectively. Microbiological results showed that the ozone treatment is effective in reducing the bacterial load by about 2.5, 1.7 and 2.0 log cycle and the fungal counts by 1.49, 1.54 and 1.1 log cycle for celery, coriander and parsley respectively. Regarding the obtained results in this study, the use of gaseous ozone to prolong the shelf life of fresh-cut herbal plants is an appreciated issue.