Cooking and leaching Black bean to remove the poison making it safe to eat. A basket was made to leach the poison out in a stream. Also shown are Atherton Oak nuts. The Aboriginal artifacts found near by were probably made by the Yidinji people (if you're reading this leave a comment below). It seems like a lot of effort to prepare black bean to eat but consider the effort that goes into making bread from scratch (plowing, sowing, winnowing, storing, milling, baking etc.). With Black bean it is collected when needed, storage is unnecessary as nothing eats it raw and it can be left in the stream till needed. It contains more energy than potatoes(but less than grain) and contains lots of starch and protein. This was a staple food of the rain forest people once.