The interior of a papaya is a deep orange color, sweet and soft. Inside it is full of black rough seeds - which are edible, although their peppery flavor is somewhat bitter. Papayas are eaten fresh in salads or juices. The fruit, as well as the other parts of the papaya tree, contain papain, an enzyme that helps digest proteins. This enzyme is especially concentrated in the fruit when it is unripe. When shopping for a ripe papaya, look for skin that is turning from green to yellow. Parts of the papaya may look bruised - this is normal. You should be able to press your thumb into the flesh. If it's too soft or mushy, or if it has a sweet smell to it, the papaya is overripe.