The present invention relates to immobilized proline-specific endoprotease, wherein the proline-specific endoprotease is immobilized on a carrier comprising methacrylate which has been functionalized with amino dimethylene, and wherein the carrier has a particle size range of 100 to 400 μm. The invention also relates to a process for producing beer comprising the steps of preparing a mash, fermenting the beer, and stabilizing the beer, wherein the beer is incubated with the immobilized proline-specific endoprotease.