Jack Bean - USDA Plant Guide
Outside of the United States both young pods and green seeds are eaten as a vegetable. Seeds are also used as a coffee substitute. The mature bean contains potentially harmful saponins, cyanogenic glycosides, terpenoids, alkaloids, and tannic acid (Udedibie and Carlini, 1998) and must be cooked before eating. There is also pharmaceutical interest in the use of C. ensiformis as a source for the anti-cancer agents trigonelline and canavanine (Morris, 1999). Jack bean seed has been promoted in developing nations as a potential source of affordable and abundant protein. It has 29.0% protein content (Adebowale and Lawal, 2004).