Pigment changes in the flavedo and endocarp of the developing pummelo, Citrus grandis `Goliath,' were investigated at four ripening stages: green, color break, almost ripe, and fully ripe. In the flavedo, chlorophyll of the green fruit decreased abruptly and was totally absent in the fully ripe, lemon-yellow fruit, which contained only carotenoids However, the total colored carotenoid content decreased from 26 μg/g in the green fruit to 5 μg/g in the fully ripe fruit. The pulp of the endocarp, characterized as "colorless," contained small amounts of chlorophyll and 0 4 μg/g total colored carotenoids which remained nearly at the same level in all ripening stages. The carotenoid pattern at the green stage of both the flavedo and the endocarp was that of the chloroplast type During ripening, the four chloroplast carotenoids decreased gradually, and typical chromoplast carotenoids-such as ζ-carotene, neurosporene, mutatochrome, cryptoxanthin, and its 5,8-epoxide-appeared The most striking phenomenon was the a...