After the beer has been bottled, it still cannot leave the abbey site. After all, it is still rather cloudy and it would not produce a head. Hence a Dubbel or a Tripel has to mature for a further three weeks, in a special cellar. This 3,500 m² cellar can accommodate 125,000 pallets of Trappist beer to allow it to mature slowly.
In this underground maturing store, the beer is protected against sunlight. This prevents ‘sunlight flavour’. There are special lights with UV filters that radiate a soft yellow light at a low frequency. The insulation ensures an energy efficient cellar without temperature fluctuations. The seasons have no effect, which is ideal for the maturing process.
The maturing cellar stays at an ideal secondary fermentation temperature of between 21 and 23° Celsius. The yeast cells absorb the oxygen in the bottles and produce carbon dioxide. That protects the beer against oxidation and ensures a splendid rich head when served.
