The Sea Beans or Box Beans
Entada is a genus of woody climbers in the pea family, Fabaceae. The genus Entada is derived from the Portuguese word dentado, meaning ‘toothed’. Entada species are known for exceptionally large and long seedpods. Their seeds are buoyant and survive lengthy journeys via rivers and ocean currents, to eventually wash up on tropical beaches. So they can be called “box beans”, “matchbox beans” or “sword beans” based on their pod appearance, or “sea beans” based on their seed distribution.
In Vietnam, Entada species are collectively called “bàm bàm” (or dây bàm, dây tràm). There are about known species:
- Entada phaseoloides – S.Thomas bean or box bean
- Entada phaseoloides subsp. tonkinensis, formerly known as E. tonkinensis
- Entada rheedii – African dream herb or snuff box sea bean (Vietnamese: bàn bàn nam)
- Entada glandulosa (Vietnamese: bàn bàn tuyến)
All these box beans species are confined to some national parks due to habit loss and the difficulty to reproduce.
It is pretty hard to differentiate among these species. First, Entada phaseoloides subsp. phaseoloides is distinguished from E.p. tonkinensis only by seed characteristics: brown, convex with angular margins in the former, while blackish purple, flat with rounded margins in the latter.
E. phaseoloides generally has larger seedpods and seeds than E. rheedii. (E. phaseoloides seed is 6-7 cm in
diameter while E. rheedii seed is 4 cam in deameter). The constriction between each seeds in E. phaseoloides is irregular, while that of E. rheedii is more regular.
Entada glandulosa is different from other by their grandular leaves.
Uses AnD PoisON WARNINGS
All those box beans have pretty much the same usage, however due to their scarcity, it’s not common to general public. Box bean seeds have a hard, glossy brown shell which can be used in the art of carving letters, or calligraphy, or as jewelry… The medicinal properties of the leaves, seeds and roots are noted but very little modern research has been conducted to verify its efficacy.
It is noted that the seeds of these Entada seeds are poisonous when eaten raw. So, they must be properly cooked in water or roasted.
In Vietnam, the box beans are harvested mainly for their medicinal potential properties, but sometimes they are used in cooking.
Box beans are gathered when they are old and dried. Green box beans are too bitter and unusable. Dried box beans then first get roasted over charcoal so that the heated essential oil will break the shells. The inner pulp has an ivory color. Those box bean pulps will then be soaked in water overnight, then sliced and get boiled on low heat. The box bean pulps are used like a root vegetable, often with pork belly and/or fish.