Effects of various oxygen atmospheres on physiology and quality in Cavendish banana and 'Hebezu' citrus fruits

Abstract

Banana and 'Hebezu' citrus fruits were exposed to various oxygen levels (5-100%) at 20°C. Rates of respiration and ethylene production were induced in both banana and 'Hebezu' citrus kept under high O2 atmospheres (O2 >21%). Respiration and ethylene production increased with the increasing of O2 level in storage atmosphere. Banana stored in O2 concentration above normal air developed the peel color to yellow stage, 90 degrees of hue angle, faster than those in normal air and low O2 atmospheres, while the degreening in 'Hebezu' citrus stored in high O2 levels did not advance over the control fruit. Low O2 atmosphere (5 and 10%) was effective in suppressing respiration and ethylene production in both fruits, and the degreening was also delayed. Banana stored under low O2 atmosphere remained unripe for 27 days and the normal ripening was found after transfer to air storage. Banana fruit in 10% O2 ripened faster than those in 5% O2. Total sugar content of banana after reaching full yellow stage in both low and high 02 atmospheres was slightly different from the control fruit, except the content in 80 and 100% O2 treated fruits which was significantly lower than other treatments. Citric acid content of high O2 treated 'Hebezu' citrus fruit maintained higher than control and low O2 treated fruits. Soluble solid content in all storage conditions increased from the beginning except for 100% O2 treated fruit, which showed the significantly lower content than other treatments and maintained the content as recorded at the initial.