Bitter gourd, like all other vegetables, goes rotten. However, each vegetable has its expiration date. Though bitter gourd has a short shelf life, it can be extended to some amount with careful storage. There is a slew of reasons why bitter gourds go sour. Bitter gourd is a green-skinned vegetable with white to translucent flesh and a bitter flavor.
It might take some time to get used to the bitter taste of bitter gourd unless you grew up eating it regularly. A variety also knows bitter gourd of other names.