The Effect of Ethylene during Controlled-atmosphere Storage of Bananas

Abstract

Banana fruit respiration rates and quality parameters such as peel color, pulp pH and soluble solids content were examined at 14°C under a number of controlled atmosphere (CA) environments. CA conditions were 1%, 2%, 4%, or 8% oxygen with or without 5% carbon dioxide. Each treatment combination was also done with or without 50 μL·L–1 ethylene added to the atmospheres. Green banana fruit were either gassed with ethylene (triggered) or ungassed. One percent oxygen was too low to consistently give undamaged bananas. The addition of 5% carbon dioxide to the controlled atmosphere increased fruit respiration rate whereas air plus 5% carbon dioxide showed decreased respiration when compared to air control fruits. Green, triggered fruit partially ripened under the CA conditions. Pulp pH and soluble solids content changed in a normal ripening pattern, however peel color was poor. Addition of ethylene to the atmospheres advanced fruit ripening somewhat in all fruit. When green, ungassed bananas were placed under CA, the presence of ethylene in the atmosphere did not cause the bananas to turn yellow, although some changes in pH and soluble solids were detectable. In triggered fruit the presence of ethylene in the storage advanced ripening with higher oxygen concentrations promoting faster ripening. Bananas that have ripened under CA conditions are not as high quality as those ripened in air in terms of visual appearance.