Spent grain is the main leftover of brewing and it represents approximately 85% of total by-products generated. However, spent grains are of high nutritive value and can be incorporated in a variety of other products. Spent grain is being used as ingredient in the production of granola bars, dog biscuits, bread, and soap. Spent grain is also being used as energy source. The combustion of spent grain using a biomass boiler produces thermal energy; it can be used as a source of sugar for bioethanol production, and through anaerobic digestion the production of biogas.
Some of the successful stories repurposing spent grain:
Portland Pet Food Company produces brew biscuit dog treats made with repurposed spent grain. Biscuits are made with high quality ingredients and sourced from local breweries.
Sfoglini is a pasta maker located in Brooklyn dedicated to sourcing high quality organic grains to bring classic Italian style pasta. In collaboration with the Bronx Brewery, they use the spent grain from its Bronx Rye Pale Ale to produce the BXB radiatori pasta.