The brewing process

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On the ale trail

There are many archaeological and historical clues to suggest that beer has been brewed for thousands of years; we now know that in Neolithic times cereals were grown both for bread-making and for beer-making and that the ancient Egyptians brewed a form of ale flavoured with herbs and spices. By the Middle Ages, everyone (including children) drank beer as part of their staple diet. Not only was it nutritious but, in the days of very rudimentary sanitation, it was far safer to drink than water!

Over time, Britain emerged as one of the world's great brewing nations. It was here that the ale we have all come to know and love was first developed.

Natural, simple, wholesome

Beer is a product of nature. It contains only the most natural of ingredients. Until the fifteenth century, beer was made using malt (derived from barley) water and yeast. It was the Flemish and Dutch brewers who added hops to the recipe – not to improve the taste of the beer but to help preserve it. Nowadays, it would be unthinkable to drink beer without the unmistakable bitterness and floral aroma of hops.

Grist to the mill

Our brewers select only the best barley from which to make malt. Malt is made by soaking the barley grain to encourage germination. At a critical point, germination is stopped and the barley transferred to large kilns for roasting. Kilning browns the malt, which adds colour and flavour to the beer at a later stage. The roasted malt is then milled to a powder, or grist – hence "grist to the mill".

Making the mash

The grist is mixed with hot water to form a porridge-like slurry – called a mash. This is pumped into a mash tun (a large copper vessel) where it stays for about an hour at a constant temperature of 65°C. The result is a solution that brewers call sweet wort (pronounced "wert").

Bitter sweet

The sweet wort is now transferred to what is really a giant kettle, traditionally called a copper. Here, the sweet wort is boiled and the hops added. Boiling continues for about an hour, after which the filtered solution – now called just "wort" – is transferred to the fermenting vessel.

Pitching the yeast

The fermentation process is started by adding – or pitching – a carefully measured quantity of yeast to the wort. The yeast converts sugar into alcohol while at the same time producing large amounts of carbon dioxide, which gives beer its characteristic sparkle. Ale yeasts generally ferment for up to five days at around 18°C and rise to the top of the fermenting vessel.

Refining the beer

The liquid produced in the fermenting vessel is beer. If it's destined to be a 'real ale', it's put straight into casks. There is still a small amount of yeast in the beer at this stage and this will perform what is called a secondary fermentation. This gives the beer its final, desired taste. The last ingredient to be added to each cask is finings, which helps settle the yeast and clear the beer ready for drinking. There are several varieties of finings but the most traditional is isinglass, the dried swim bladder of the sturgeon fish!

The perfect pint

Cask ale is a living product and will only keep in an unopened cask for 35 days. Once opened, the beer must be consumed within three days. It requires critical storage conditions and skilled handling. Our licensees are given practical support, training and advice to ensure that this amazing, living product is provided with the best tender loving care - so that you, the customer, can enjoy the perfect pint every time.

The skill of the master brewer

The process of brewing beer may be simple but it takes the skill of a master brewer to produce the individual blends and recipes for each beer. Here at Greene King, our brewers have created arguably the finest range of cask ales available in the UK, each with its own flavour, aroma and characteristics.