Abstract
Abstract
Vegetables preservation, including tomatoes, is challenging with limited available preservative means during postharvest storage. Gaseous ozone, as a substitute postharvest sanitizer, was evaluated for its effectiveness on tomato storage. Fruits were subjected to ozone enrichment (0, 0.2, and 1.5 ppm) for 2 or 6 h at 13 °C and 95 % relative humidity, and then they were stored in clean air up to 8 days. Control treatment was considered storage in clean air, without (0 ppm) ozone. Increased ozone levels resulted in increased fruit respiration rates, ripening, and lipid peroxidation, indicating oxidative stress responses. The application of ozone triggered ascorbic acid content (up to 53.3 %) while the highest ozone dose of 1.5 ppm for 6 h maintained fruit firmness (up to 16.3 %) and resulted in increased weight loss as compared to control. Ozone application of 1.5 ppm for 2 h revealed the highest lycopene (1.3 mg/100 g) and β-carotene (0.69 mg/100 g) content compared to the control (non-ozonated) fruit. Ozone treatments did not affect fruit aroma, appearance, marketability, colour indices, total soluble solids and total phenols. Fruits exposed to low ozone doses (concentration and time duration), maintained and/or improved quality indices, especially antioxidant content. Short time ozone application may trigger fruit metabolism and stimulate antioxidant reactions to deal with the oxidative stress challenge.