The flux during membrane filtration can be enhanced by the use of a two-phase gas-liquid flow. This has been shown to be an energy-efficient alternative to increasing the cross-flow velocity. In this work, air sparging was used to increase the flux during ultrafiltration of alkali-extracted wheat bran hemicelluloses. Batch filtration was performed in a pilot unit with a ceramic ultrafiltration membrane with a nominal cut-off of 10 kDa. Parametric studies with and without air sparging were performed at temperatures of 30 degrees C, 50 degrees C and 80 degrees C and cross-flow velocities of 1, 3, 5 and 7 m/s. The limiting flux was not affected by air sparging at 30 degrees C, while a slight increase was observed at 50 degrees C and a considerable increase was obtained at 80 degrees C. Air sparging reduced the energy demand per m(3) permeate produced during deadend batch ultrafiltration at 80 degrees C and 1 m/s from 0.96 kWh/m(3) to 0.51 kWh/m(3). (C) 2018 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.