Abstract
The effects of controlled atmosphere (CA) at 5, 21 (air, control) and 100 % O2 on chilling injury, respiratory and antioxidative parameters at 5, 10 and 20°C in cucumber fruit were determined. The appearance of chilling injury symptoms in cucumber was delayed in both CA treatments; 100 % O2 effectively reduced pitting than did the 5 % O2 treatment. Respiration and ethylene production rates were suppressed in cucumber fruit stored at 5°C to a greater extent in 100 % O2 than in 5 % O2 and air. At 20 °C, however, 100 % O2 increased the respiration rate to rates higher than in 5 and 21 % O2. The respiration rate of cucumber fruit stored in 100 % O2 at 10°C was lower than control but higher than the fruit stored in 5 % O2. Analyses of fruit for changes in enzymatic antioxidant; superoxide dismutase (SOD) and catalase, and non-enzymatic antioxidant, ascorbic acid and glutathione revealed that those stored at 5°C, SOD activity temporarily increased on D-1 by 5 and 100 % O2 treatments; at D-5, its activities in all storage atmospheres increased. Catalase activity in the control fruit was higher than those at both 5 and 100 % O2, whereas glutathione concentration changed slightly from the initial level at different storage conditions. Ascorbic acid content in all storage atmospheres decreased, exhibiting the same trend throughout the storage period.
