BEAN 'Jack' --Canavalia ensiformis--

AKA sword bean, and eaten especially in Brazil where it is called feijão-de-porco ("pig bean"), and many other nicknames. Perennial vine of unclear origin with large leaves and long seeds pods, widely cultivated for its large seeds which are edible after boiling. The beans are mildly toxic, containing an alkaloid called concanavalin A., and copious consumption should be avoided. Boiling will, however, remove toxicity from con A. if done properly - requires 3 h of cooking at 96°C or 45 min of pressure cooking; 48 h of soaking the seed in water prior to cooking for 2 h; 72 h of soaking in water prior to ordinary cooking for 1 h; pressure-cooking for 15 min, to completely eliminate it from the seed. Complete inactivation of Con A in the seed can, however, be easily achieved if the seed is broken into pieces and cooked for 1 h or pressure-cooked for 15 min.. Young foliage is also edible.