Custard apples yield to the touch when ripe. If ready for consumption, the white flesh inside will be slightly visible in between the fruit’s bumpy protrusions.Unripe fruits have a dark, green skin and do not yield to the touch. Overripe fruits, on the other hand, fall apart in the hand and have a black exterior. They also lose their sweetness and have a bland, mildly musky flavor.Many farmers pick Annona fruits before they’re fully ripe, as they continue to ripen once.