By-Products Of Brewing

Written by Steve Cannon on January 1, 2022

Spent Grain & Dregs

Brewing by-products are “spent grain” and the sediment (or “dregs”) from the filtration process which may be dried and resold as “brewers dried yeast” for poultry feed or made into yeast extract which is used in brands such as Vegemite and Marmite. The process of turning the yeast sediment into edible yeast extract was discovered by German scientist Justus von Liebig.


Brewer’s spent grain (also called spent grain, brewer’s grain or draff) is the main by-product of the brewing process; it consists of the residue of malt and grain which remains in the lauter tun after the lautering process. It consists primarily of grain husks, pericarp, and fragments of endosperm. As it mainly consists of carbohydrates and proteins and is readily consumed by animals, spent grain is used in animal feed. Spent grains can also be used as fertilizer, whole grains in bread as well as in the production of flour and biogas. Spent grain is also an ideal medium for growing mushrooms, such as shiitake, and already some breweries are either growing their own mushrooms or supplying spent grain to mushroom farms. Spent grains can be used in the production of red bricks, to improve the open porosity and reduce thermal