The mixed matrix membrane (MMM) concept is extended, for the first time, to produce a hydrophobic interaction chromatography (HIC) membrane using crushed Phenyl Sepharose (TM) (GE Healthcare Technologies, Uppsala, Sweden) resin and tested for use in whey protein fractionation. The HIC MMM had static binding capacities (membrane volume basis) of 18.419 +/- 0.605 mg mL(-1) for beta-lactoglobulin, 45.850 +/- 2.753 mg mL(-1) for alpha-lactalbumin, 41.106 +/- 9.004 mg mL(-1) for bovine serum albumin and 42.467 +/- 4.130 mg mL(-1) for lactoferin in individual protein solutions. For flowthrough whey fractionation, the adsorption performance of the HIC MMM was similar to a HiTrap (TM) Phenyl (GE Healthcare Technologies) HIC column. However, the well-known high processing speeds and inherently low pressure drops of MMM chromatography may offer benefits over a conventional packed bed column. (C) 2013 Elsevier B.V. All rights reserved.