St Patrick's Day: The secrets of Guinness
If you could bottle the essence of Ireland, it's a fair bet that it would be made from pure Guinness, the Emerald Isle's most treasured export and one of the most famous beverages in the world. There's never a better time to drink it than today, St Patrick's Day, but how much do you know about it?
Guinness was created by Arthur Guinness, who set up the famous brewery at St James's Street in the heart of Dublin. Many other stout breweries have tried to capture the essence of Guinness but failed. Despite centuries of speculation that Guinness uses a secret ingredient or a closely guarded brewing technique, there are actually only four natural ingredients that go into your pint of stout.
Barley
The brewery roasts barley grains to give Guinness its deep ruby colour - not black as it's so often wrongly described. Barley also provides the starch and sugar for the brewing process through malting. The grains used to produce the malt are steeped in water until they begin to swell and start to sprout little shoots. This means the starch is beginning to be converted into sugar. The barley is then quickly heat-dried to stop further germination.Water
Contrary to popular belief, the water used in brewing Dublin's Guinness doesn't come from the River Liffey running through the city's heart but from springs fed by the St James Well in County Kildare.A little roasted barley is mixed with the malt before being thoroughly mashed with hot water in large rotating drums called kieves. This produces a sugary liquor called the wort, which takes about 18 hours.
Hops
It's the female of the species that is used in the brew. Hops add flavour and aroma, but also act as a powerful natural preservative that made it possible for Guinness to be transported all over the world in the days of steam trains and long sea voyages.The wort is drained off and then transferred into a "copper" - a giant 600-barrel capacity kettle - and the hops are added to this. It's all boiled vigorously for some hours to extract the best from the hops before being strained off and moved on for fermentation.
Yeast
No one knows where Arthur Guinness got his first batch of yeast. Because some yeast from each brew is transferred on to the next, this original yeast's descendants are still in production today.This original yeast is so valuable to the company that some is kept locked in the director's safe so that if anything were to happen to the main supply, the small reserve culture could replace the entire stock in a matter of hours.
The brewery's treasured yeast is thrown, or "pitched", into the hopped wort. Yeast is a fungus with a ferocious appetite. It feeds on the sugary liquid creating alcohol and carbon dioxide along the way, reproducing itself rapidly to take advantage of all the goodness surrounding it. This activity can churn things up so much it looks as if the liquid is boiling. The result is stout but it's known as green beer.
Maturing and blending
The green beer is run into storage vats and left in the maturation vessels to allow that flavour to develop. It is then clarified to remove any remaining yeast. This, just one important step away from the end product, is called bright beer.Due to the natural variation during any production process, the bright beer is sampled and blended to produce a consistent stout of excellence. Guinness says there are currently no vacancies for this job.
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