Brewer's spent grain

Brewer's spent grain, also called draff, is the solid residue left over after wort is extracted during beer brewing, and it makes up around eighty-five percent of the total waste produced by the brewing process. It comes out of the brewery with a high moisture content but can be dried for longer storage, and because it is abundant, cheap and rich in protein, fiber, cellulose and hemicellulose, it has found reuse as a food additive, livestock feed, fertilizer and even as a material in ceramics.