Maturation of green beer (immature beer) is required to refine the finished aroma, flavour and clarity of lager beer.
The main objectives of green beer maturation are flavour adjustment (diacetyl, SO2 and DMS), yeast sedimentation,
carbonation and colloidal stability. Maturation can be divided into two parts, the first being the warm (ruhr) maturation and the second a cold (lagering) process.