Sparging, Heating & Aroma
After an initial period of some 20 minutes or so a fine spray of hot liquor is sprayed onto the surface of the mash. This process is known as sparging. Sparging lasts for approximately an hour, and during that process all the fermentable sugars are washed out from the mash into the wort kettle. At this stage the beer will take on the colour of the coloured malts and will end up at a gravity marginally above the final gravity required for fermentation. Once the wort kettle is full the wort is heated to boiling by external steam jackets. Once a rolling boil has been established the bittering hops are added. These hops are then boiled for 70 minutes. Aroma hops are added before the end of the boil and these are designed to give a unique in-glass aroma.
