Effect of a milling pre-treatment on the enzymatic hydrolysis of carbohydrates in brewer's spent grain

► BSG has the potential to be a valuable source of food, chemicals and energy. ► The overall enzymatic release of BSG carbohydrates was improved 2-fold by milling. ► The choice of the milling technique affected the particle size and hydrolysis yield. ► Initial hydrolysis rate increased with milling improving the overall solubilisation. ► Milling affected the solubility of cellulose more than that of arabinoxylan.