Changes in pigments in pulp and aril of Balsam pear (Momordica charantia L.) fruit during development and storage

Pigments of Balsam pear (Momordica charantia L.) fruit during development, ripening and storage were investigated to determine the optimum horticultural stage and temperature management of the post-harvest fruit and also to obtain data, on their carotenoid composition. The fruit were harvested at six stages (A, B, C, D, E and F) of development and ripening. The fruit harvested at stage C (horticultural maturity) were packaged with polyethylene film bags and stored at 1, 10, 20 and 30 degrees C. The pigments of balsam pear fruits during development and storage were analyzed quantitatively by HPLC. The main composition of carotenoids was lutein with a minimal quantities of beta-carotene and alpha-carotene found in the pulp as well as in the aril of young balsam pear fruits. Both chlorophyll and total carotenoid contents decreased steadily during fruit development from stage A to D. However, the total carotenoids increased significantly while the chlorophyll disappeared completely during stage E to F. The highest content of carotenoids was found in ripe fruit (stage F) and the principal components were lutein and cryptoxanthin. The carotenoid content in the aril increased considerably during fruit ripening, lycopene being the main component, reaching 64.75 mg/100g FW at stage E. Both chlorophylls a and b contents decreased significantly in the fruit stored at higher temperature than at lower temperature. The lutein and cryptoxanthin contents in pulp increased during storage at 20 and 30 degrees C, but increased slightly or tended to decrease during storage at 1 and 10 degrees C,respectively. The pattern of changes of carotenoids in the aril was similar to that of the pulp.