Early detection of abnormal skin ripening characteristics of 'Kensington' mango (Mangifera indica Linn).
Jacobi, K. K.; MacRae, E. A.; Hetherington, S. E.;
Scientia Horticulturae Year: 1998 Vol: 72 Issue: 3/4 Pages: 215-225 Ref: 23 ref.
1998
บทคัดย่อ
Changes in skin colour and chlorophyll fluorescence of Kensington mangoes were measured daily on fruits harvested at the green mature stage and stored at 22 deg C until ripe. Fruits were sourced from two sites, Gin Gin and Eumundi, within the one production region, SE Queensland. The skin colour parameters of colour rating (1-6 scale), reflectance, chroma and hue angles, as well as the chlorophyll fluorescence parameters, FO (minimal fluorescence) and the Fv/Fm ratio (the ratio of variable fluorescence to maximum fluorescence, where Fv = Fm - FO), were measured. Fruits from the Eumundi orchard ripened normally with skin colour increasing from green to yellow following an approximate sigmoidal pattern. The FO parameter followed skin colour development closely, but the Fv/Fm ratio remained constant for 7 days, before declining. Fruits from the Gin Gin orchard were considered 'green ripe' as they did not degreen fully in parallel with the softening associated with fruit ripening. With these fruits,
the FO values remained higher than with Eumundi fruits and did not decline as rapidly during storage at 22 deg C. Regression analyses revealed a high linear correlation between the subjective skin colour rating and the objective measurements of reflectance, chroma, hue angle and FO for both Gin Gin and Eumundi fruits. Because of its rapid measurement time, FO shows potential as a commercial nondestructive measurement for scanning Kensington mangoes early in the postharvest handling chain to detect and separate any fruits that have the potential to 'green ripen', thus minimizing losses in the market through unsalable fruits.