The Sopophorous Bean is a small, rare, pearly white bean, resembling overgrown mistletoe berries, which sprouts in gloomy marshlands, especially if fertilized by mooncalf dung. It contains a thick silver juice that will remove the drinker's memory if drunk neat. Its juice is an ingredient in making the Draught of Living Death.
The juice of the Sopophorous Bean is difficult to extract. Typically the bean is cut to release the juice, although this is tricky to do. In their annotated copy of Advanced Potion Making, the Half-Blood Prince suggests crushing the bean with the flat side of a silver dagger, which releases the juice much better.