Brewing requires four ingredients: water, barley, hops, and yeast. One of the most exciting things about brewing is that there is so much diversity from only four raw materials. Here’s a snapshot of our beer’s fascinating journey from grain to glass.
The careful, unhurried brewing process begins in the mill room. Here, malt made from carefully selected Cornish Maris Otter barley is precisely measured, hoisted, and crushed to grist using the old mill which sits at the top of the brewery tower and dates back to 1887. It takes four tonnes of malt to make each brew, which yields over 45,000 pints of beer.
This is where water (referred to by brewers as ‘liquor’) enters the process. On the floor below the mill, the milled malt (grist) is mixed with liquor. They enter the mash tuns together to create a thick porridge-like mixture called the ‘mash’. The mash will rest at a temperature of exactly 65°C for 90 minutes. During this time, the starch from the grain converts to fermentable sugars via the natural enzymes in malt.
The next stage involves draining all the fermentable extract from the grain bed by sparging hot water through. The resulting ‘wort’ is then transferred to the copper.
The wort flows into the Copper where it is boiled with hops to give the beer its flavour. The copper (or brewing kettle) lies on the floor below the mash tun and is where the hops are added to the sweet wort before being boiled vigorously for 75 minutes. The wort is then filtered through a further bed of hops before passing through a cooler where the temperature rapidly drops from boiling to just under 15°C.
Now the cooled wort is pitched with yeast and run into one of 14 fermenting vessels, where it remains for one week. Yeast feeds on the malt sugars in the wort to yield alcohol and carbon dioxide. As this happens, a huge foaming yeasty head forms on the surface of the fermenting beer. Towards the end of the fermentation, this yeast is skimmed from the surface of the brew and stored ready to feed the following week’s batch.
After fermentation, each brew is carefully checked in the laboratory to ensure that it’s ready for racking (filling into casks).
Natural and wholesome, this ‘living’ beer still contains residual yeast which is required to fuel a secondary fermentation in the sealed cask. This process gives cask beer its ‘condition’ (a natural sparkle). Cask beer contains no additives – only natural finings are added to the cask to help the yeast settle in the pub cellar before the beer is ready for serving.
After racking, each brew must undergo the most detailed scrutiny of all. A sample cask is stillaged (settled and tapped) for tasting by the Head Brewer and a small team of expert tasters. Only when they are satisfied that the exacting standards have been achieved can the beer leave the brewery to be enjoyed by customers around the world.