Changes in respiration rate, saccharide and organic acid content during the development and ripening of mango fruit (Mangifera indica L. 'Irwin') cultured in a plastic house.
Ito, T.; Sasaki, K.; Yoshida, Y.;
Journal of the Japanese Society for Horticultural Science Year: 1997 Vol: 66 Issue: 3/4 Pages: 629-635 Ref: 22 ref.
1997
บทคัดย่อ
Seasonal metabolic and chemical changes in developing mango (Mangifera indica cv. Irwin) fruits cultured in a plastic house at the Yuasa Experimental Farm, Yuasa-cho, Wakayama Prefecture, Japan, were investigated. Fruits were selected which had developed from 14 June (young-fruit stage) to 21 August (mature green stage), and which were picked at mature green stage on 2, 8 and 21 August and stored at 25 deg C, were used. The changes in respiration rates, soluble sugars and starch, and organic acid contents were determined. The fruits enlarged rapidly before the endocarp started to harden on 4 July, but enlargement slowed after the hardening process stopped on 19 July. The respiration rates of fruits during development declined rapidly until 19 July, but afterwards remained steady. Postharvest respiration reached a maximum value on the 1st or 2nd day after the onset of the climacteric rise. The beginning of colouring and flesh softening coincided with a respiration rate peak. The fruits developed
an aroma a few days after colouring. At harvest on 21 August, fructose and sucrose contents were 3.4 g/100 g and 1.9 g/100 g FW, respectively, whereas, glucose content was 0.2 g 100 g FW-1. Fructose was the predominant sugar during development. Starch content increased rapidly from 2.1 g 100 g FW-1 to 11.7 g 100 g FW-1 between 19 July (completion of endocarp-hardening) and 21 August. After ripening, starch became almost undetectable, whereas sucrose increased significantly; fructose increased slightly. As a result, the major sugar was sucrose with the majority of the reducing sugar being fructose. Thus, if the mature green stage fruit has high starch content, it tends to have a high sugar content at the full ripe stage. Of the organic acids, citric and malic acids were detectable, the former being more abundant than the latter. Citric acid content increased to a maximum of 1.4 g 100 g FW-1 at the beginning of the endocarp-hardening period then decreased steadily to 0.6 g 100 g FW-1 on 21 August. It decreased
further in fully ripe fruits. Based on these data, it is suggested that the time when the skin begins to turn red and/or yellow on the tree, is the optimum harvest stage for Irwin mango fruits cultured in a plastic house.