EFFECT OF PRESTORAGE TREATMENTS ON MANGO FRUIT RIPENING

The effectiveness of pre-storage treatments of nitrogen (low oxygen), heat and ethanol and acetaldehyde vapours were examined for their pote ntial for improving mango storage. Mature green mango fruit (Mangifera indica L. cv. Keitt) were treated with low oxygen (<3% oxygen, 97% ni trogen) for 72 h, acetaldehyde (0.12%) and ethanol (1%) vapours for 24 h or heat (38 +/- 2 degrees C) for 48 h prior to storage at 14 degree s C. The nitrogen and ethanol treatments induced substantial levels of acetaldehyde and ethanol in the fruit. Initially the firmness of the nitrogen treated fruit remained higher than the control although later in storage this effect was lost. Differences in ripening were reflect ed in the total soluble solids and acidity levels, nitrogen maintainin g a higher acidity and lower total soluble solids (less mature) wherea s the heat treated fruit had lower acidity and higher total soluble so lids (more mature). Ethanol and acetaldehyde treatments showed no effe ct. The use of a pre-storage treatment of nitrogen therefore had a ben eficial effect on retarding ripening, although as storage progressed t his effect was lost.