Whisky co-products – new uses for a Scottish resource

Scotland is famous for its whisky – a proud tradition stretching back over 500 years. There are approximately 100 malt whisky distilleries in Scotland with the capacity to produce over 280 million litres of alcohol per annum. Production also results in co-products; primarily draff, the malted barley fraction remaining after the sugar-rich media has been extracted for fermentation and pot ale, the liquid residue remaining after the separation of alcohol during the first distillation stage. Co-products are traditionally used as low-value animal feed although recent uses have included treatment in combined heat and power plants and further processing and fermentation to biofuels. These co-products are valuable protein resources and to secure their use in feeds, we are developing efficient and cost-effective processes to extract the protein in addition to other components. This will add value to the whisky co-products and open up new markets for their use.
One ideal use is in aquaculture. Salmon is Scotland’s largest food export and with 158 thousand tonnes of salmon produced in 2012, an estimated 85 thousand tonnes of protein is required annually. Most of this protein is imported, either as fish meal or soya bean meal. The ethics and sustainability of these feeds are debatable and the use of proteins from whisky co-products will provide a local solution for the Scottish aquaculture industry.