β-Glucanases

Enzymes that hydrolyse β-glucans, the viscous glucose polymers of cereal cell walls. Their most important application is in brewing: barley β-glucans raise wort viscosity, slow filtration, and cause haze and gushing in beer, and β-glucanase treatment during mashing breaks them down, improving lautering, filtration, and colloidal stability. Maltsters select barley varieties and malting regimes partly for their β-glucanase potential. They are also added to animal feeds based on barley and oats to reduce gut viscosity in poultry, improving nutrient absorption. Their activity is a key malt quality specification, and insufficient β-glucan breakdown is a classic cause of brewhouse trouble.