Dewatering of brewer’s spent grain using an integrated membrane filter press with vacuum drying capabilities

ABSTRACTBrewer’s spent grain (BSG) is a by-product of the brewing process, rich in fiber, protein and carbohydrates. Its potential application is limited because of high moisture content (80%). This work presents a process for dewatering BSG using two different sets of membrane filter plates in a filter press with vacuum drying: recessive plates with polypropylene membranes and the innovative Rollfit® plates. A final moisture content of 12-15% was obtained in 15 mm-thick filter cakes, using both types of plates. The dewatering cycle included filtration, membrane-squeezing, and vacuum thermal drying using hot water (~90oC) as heat source.