Bitter Gourd
This edible fruit is one of the most bitter vegetables produced. The elongated fruit has a rough exterior and a crunchy, watery flesh which is bitter. When the fruit is green, the skin is edible whereas the pith is removed before cooking. The pith becomes sweet and red when ripe and is used uncooked in various salads.
Also known as bitter melon, it originated in India. It is eaten in the green or early yellowing stage. It looks somewhat like a cucumber (shape wise) with a spiky exterior.