Studies on keeping quality of imported 'Carabao' mango fruit from the Philippines.
Tsuda T., Chachin K., Ueda Y.
Author Affiliation: College of Agriculture, Osaka Prefecture University, Gakuen-cho, Sakai, Osaka 599-8531, Japan.
Journal of the Japanese Society for Horticultural Science 68 : 669-674
Abstract : The effects of packaging Carabao mangoes, imported from the Philippines to Japan in polyethylene (PE) bags, with and without perforations, and kept at 20°C, were investigated. Their appearance, using a 6-point numerical peel color index (PCI), sugar and organic acid contents, and their tendency to shrivel were assessed. Portions of the peel still remained greenish after day 7 in PE20 bags although fruit maturities, which were ranked as PCI-2 and PCI-3 initially, advanced to PCI-4 and PCI-5, respectively. The Hunter a value which increased in both the peel and flesh with time, was lower in the fruit packaged in PE20 bags than it was in unpackaged fruits (control) or those packaged in the perforated PE bags. Starch content in PCI-2 fruits was higher than in PCI-3 fruits but it rapidly decreased during the first day of storage. Sucrose was the predominant sugar in Carabao mangoes. The total sugar, sucrose and fructose contents increased during storage. The tendency for sugar to increase was slower in the fruit in PE20 bags than in the others. Sugar content in PCI-2 fruits in perforated or PE20 bags was lower than that in PCI-3 fruits. Glucose content decreased in the control or perforated PE bags faster than it did in fruits in the PE20 bags. Citric acid which is the predominant organic acid in Carabao mangoes was initially higher in fruits at stage PCI-2 than in those at PCI-3; it decreased during storage. The tendency for citric acid to decrease in fruit in the PE20 bags was slower, but its level was similar that in control fruits and those kept in perforated bags. Malic and succinic acids were also found in Carabao mangoes but remained at a low level during storage. Shrivelling, which occurred in the peel of PCI-2 and -3 fruits, began on day 5 in control fruits and on day 7 in perforated PE bags, at which time the water loss was about 7%. Shrivelling did not occur in fruits in PE20 bags at PCI-2 or PCI-3. Packaging PCI-3 fruits in perforated PE bags did not prevent increases in sugars, decreases in organic acids, nor advancement in flesh and peel colour or water loss as compared with those at PCI-2. It is recommended that Carabao mango fruits at PCI-3 should be imported in perforated PE bags because they were the most effective in maintaining quality.