Westmalle Trappist brewery chooses a long boiling time of ninety minutes. Enough water thus evaporates off so that the wort achieves the right density. This duration also gives the brewer time to add the hop cones at three different times.
The boiling dissolves the active components of the hops, thereby releasing the bitter flavour and the separate hop aroma. Moreover, this process sterilises the wort and substances are produced that protect it against oxidation. While boiling, the ‘casse’ also forms: proteins coagulate as a result of the heat whereby they can be easily removed. After boiling, the wort has to be cooled to around 20° Celsius
