Evaluating the efficacy of applying gaseous ozone to fresh-cut romaine lettuce

Fresh-cut lettuce has become a staple in modern diets due to its convenience and year-round availability. However, it has a relatively short shelf life and is prone to deterioration if not adequately packaged and stored. The objective of this study was to evaluate the influence of varying gaseous ozone concentrations on some physical and biochemical attributes of fresh-cut romaine lettuce that contribute to its overall quality. Fresh-cut lettuce was exposed to 1, 5, 10, and 20 ppm of gaseous ozone for 2 min and then stored in clamshells at 4 °C for 15 days. Various physical and biochemical characteristics were monitored throughout the storage period, and the total aerobic count was determined on the final day of the experiment. Ozone demonstrated ameliorative effects on respiration rate and microbial load by suppressing both parameters. However, higher concentrations adversely affected titratable acidity, visual quality, and soluble solids, particularly after 10 days of storage. The study highlights the complex and multi-faceted impact of gaseous ozone on fresh-cut romaine lettuce, demonstrating that depending on the parameter, the effects may be beneficial, negligible, or detrimental.