Combined enzymatic and crossflow microfiltration process to assure the colloidal stability of beer

In this work, two beers of the industrial and craft types were stabilized and clarified by combining a commercial enzyme preparation of fungal origin (Brewers Clarex ® ), which is commonly used for the production of gluten-free beers, with crossflow microfiltration . By resorting to some European Brewing Convention indicative forcing tests (i.e., sensitive proteins, alcohol chill haze, and chill haze development), it was possible to confirm the efficacy of the enzyme preparation for both beers examined. By combining the enzymatic and polyvinylpolypyrrolidone (PVPP) treatments, each beer exhibited a greater colloidal stability with respect to that achievable with any single treatment. Independently of the stabilizing pretreatment used, final membrane clarification gave rise to permeated beers with almost the same chill haze development. By coupling the enzymatic treatment to crossflow microfiltration , it would be possible to replace PVPP, and avoid its expensive recovery and regeneration processes, thus leading to a simpler one-step beer conditioning process. • A single step beer conditioning process was tested on two beers of the industrial and craft types. • It avoided using PVPP, and its expensive recovery and regeneration processes. • For both beers the efficacy of the enzyme treatment was assessed by conventional forcing tests. • Whatever the pretreatment used, membrane-clarified beers exhibited almost the same chill haze.