Take a Private Tour of the Guinness Brewery. Homebrewers Only!
The Guinness brewery in Dublin, Ireland, is a time machine. Cobblestone streets link the gray stone and red brick buildings — narrow thoroughfares where draft horses once clopped their way around the sprawling complex, hauling malt, hops, kegs, and men from job to job, batch to batch.
Today, diesel trucks and forklifts ply these time-worn paths of stone. Rubber tires roll over the iron tracks of the brewery’s narrow-gauge steam railway system, built in the late 1700s to supplant horse-drawn transport.
The brewery complex is a tapestry of old and new. Guinness brewers oversee 21st century computer-automated brewing in the shadow of Arthur Guinness’ original brewery and residence, for which he invested £100 (about $150 today) of inherited funds in 1759.
Guinness made a real estate deal that would make any modern businessman jealous: a 9,000-year lease at £45 per year, with water rights included.
Of course, at the time £45 was nothing to sneeze at. And the property was nothing to brag about. Only four acres, it was small, already 90 years old and broken down. It had been sitting idle for nearly 10 years when Guinness made his deal for one of dozens of nondescript breweries in Dublin’s industrial quarter, known as the Liberties. Located at St. James Gate, one of the gates in the old wall surrounding Dublin, the brewery Guinness bought consisted of a copper, a mash/lauter tun, two malt houses, a mill, stables for 12 horses, and a loft that could hold 200 tons of hay.
Guinness was an ale man. Ale was the true King of Beers in those days, and Guinness went about producing ale for Dublin. Later, a newfangled style caught his attention: porter from England.
Porter, it is said, was invented by accident. According to one theory, Porter was born when London brewer Samuel Harwood left his malt in the kiln to dry a bit too long. The grain was roasted dark, almost black. Not wanting to let it go to waste, the thrifty Harwood brewed his beer with it anyway. The resulting beer was very dark, almost black, with a roasty flavor and aroma that made Harwood want to throw the whole thing away. Then a curious thing happened: The beer became immensely popular with the porters working London’s theater district.
Harwood and other London brewers continued making it and eventually exported it to nearby Ireland. The trend grew there, and Guinness tried his hand at the newly imported style.
Porter’s popularity expanded in Ireland, and Guinness eventually was faced with what would become a historic decision. Making both ale and porter was not economical — he had to decide on which to spend all his efforts. He chose the latter. In 1799, late in the pioneer brewer’s life, he made a diary entry: “Today I brewed my last batch of ale.” Four years later Arthur Guinness died at the age of 78, after sowing the seeds of one of the world’s most successful brewing firms and one of the world’s most distinctive beers.
Before he died, Guinness tinkered with the porter style and came up with what the world now calls stout. He made it stronger, darker, and richer, a porter called “Extra Stout” to differentiate it from competitors.
The rest, as they say, is history. As Ireland’s transportation network expanded, so did the stout market. The black beer of Dublin made its way to a thirsty public, floating on barges plying the River Liffey and later the country’s canal network. The beer’s reputation spread and Guinness became a hot commodity for merchants around the world.
Today, Guinness makes stout, ale, and lager in breweries around the world. But the Dublin brewery is still devoted to the original, flagship brand, Guinness Stout. The Dublin brewery produces four million pints every day: figuratively enough for every man, woman, and child in Ireland to have a pint a day. Roughly 40 percent of the brewery’s output is bulk-shipped to canning and bottling facilities. Sixty percent goes to the keg lines. Of the beer that is kegged, 45 percent goes abroad. In fact all the kegged Guinness Draft consumed worldwide is produced at the 65-acre Dublin plant.
Another product of the Dublin facility is the mysterious Guinness flavor extract. Mysterious because no one inside the organization is willing to say exactly what it is. The many Guinness breweries located throughout the world use it to create Guinness Stout for their own markets, employing local raw materials for a base product and blending in the flavor extract to complete the job.
The flavor-extract method ensures quality and consistency in all the world’s Guinness, no matter where it is brewed, be it Africa, Asia, the Caribbean, or any other of 40-some breweries that produce Guinness in some form or another worldwide. Dublin lies at the heart of all the world’s Guinness.
Americans, however, do not have to concern themselves with the flavor-extract method. The Guinness Draft that your favorite American pub is pouring is exactly the same as the stuff they pour in Dublin. One of the myths surrounding Guinness is that it’s better in Dublin than in the US. Not so. Guinness has pioneered the use of nitrogen as a draft gas and its specially designed keg-handling and tapping system is the same in both Ireland and the States.
Dublin’s City within a City
Presiding over the Dublin operation is Matt Murphy, a slender, tall man. Murphy is pleased about America’s beer renaissance. “With the microbrew phenomenon, opportunities for craft-made and unique beers like Guinness abound,” he says.
The operation Murphy oversees is impressive. Six hundred people work at the Dublin brewery. Four hundred are employed directly in brewing operations. They use 40,000 metric tons of Irish barley each year. In fact some Irish farmers grow nothing else and sell to no other company.
Guinness malts its own barley but no longer at the Dublin site, where a traditional floor-malting was employed until recently. Now, the grain is malted throughout the Irish republic before arriving in Dublin by truck. A portion of the grist for Guinness is raw and a portion is roast, made from barley roasted on site at Dublin.
The roastery is impressive, steeped in a delicious roasted-coffee aroma emanating from the warm grains. The roastery operators oversee two enormous gas-fired drum roasters, each with a capacity of three metric tons. They roast some 13,000 tons each year — around 28.6 million pounds.
Each roaster has a sampling scoop built in, which the roast operator uses to draw out several handfuls of hot grain. He then dips in a special tool that sorts out several grains and stands them on end. A flip of a finger and a built-in blade neatly cuts each of the grains in two, so the roast operator can look inside to see the progress of color through the kernels. The lion’s share of grain for the roasters is raw barley. But a percentage of malt also goes through the roastery.
“We sell a fair amount of Guinness Stout in Germany,” explains Gerry McGovern, Dublin’s production manager. “The Reinheitsgebot, Germany’s beer-purity law, allows only malt to be added to beer. So to maintain German standards, we roast barley which has been malted,” McGovern says. It could be argued that roasted barley is the ingredient that makes Guinness what it is. It certainly is what contributes to its nearly black color and hearty, roasty flavor and aroma.
But the amazing, almost extraterrestrial creamy white head is perhaps Guinness’ most dramatic trademark. Dense, thick and everlasting; for Guinness fans, drinking a properly pulled pint is a religious experience. Watching and waiting for the perfect head to rise in a gentle dome above the rim of the glass, then nursing it down to the last swallow.
Engineering that incredible head involves a variety of important ingredients and techniques. It starts with raw, unmalted barley in the mash. Raw barley is revered by brewers for its ability to increase head formation and retention.
But until recently, raw barley was tough to deal with. It is one of nature’s hardest, most stubborn cereals, difficult to grind by standard methods. The average grain mill cannot handle it, so it traditionally was flaked by a separate process before being added to the grist for Guinness.
Flaking involves passing the tough little barleycorn through huge industrial rollers, which exert enormous pressure. The product is small flakes of barley, somewhat resembling oatmeal. In fact the building that dominates the Dublin complex is the tall, white concrete flaking plant, emblazoned with the word “GUINNESS” in huge, red neon letters. Until recently, all the raw barley added to Guinness was flaked there. But modernization has seen the flaking plant become obsolete and it is no longer in use.
“Flaking was made extinct by modern milling technology. The new mills are so good that flaking is no longer a prerequisite to mashing,” McGovern explains. The raw barley goes straight into the new mills, and they handle it just fine.
McGovern notes that unlike those in corn and rice, the starches in raw barley do not have to be gelatinized before mashing. So no cooking is required. The enzymatic action of pale malt is strong enough to convert the starch into the sugars required for fermentation. So you won’t find any cereal cookers at the Guinness plant.
Guinness’ new brew house is laid out in the traditional, top to bottom design. Though the grains are not milled on the top floor, they are sent there by conveyor for storage in the huge grist bins. To mash a batch of Guinness, you’ll need 22 tons of grist (48,501 lb.) of around 65 percent pale malt, 25 percent raw barley, and 10 percent roast. Add that to 50 tons of water (13,233 gallons) in the mash tun, where huge, automatic paddles and knives rotate through the mash to keep it loose and well-mixed.
The water comes from Ireland’s Wicklow mountains. It’s relatively soft, but with the right blend of minerals for a successful mash. It’s the same water that Arthur Guinness used to make stout back in the 18th century.
The mash rests at 65° C (135° F) for 75 minutes, then it is stepped up to 67° C (152.6° F) and held for 45 minutes, then mashed out at 78° C (172° F).
The mash is fully converted in just over two hours, but the whole process takes about three. After mash-out it is automatically transferred to the kieve (pronounced “keev”).
“Kieve is a term unique to Ireland,” McGovern says. “Most breweries call this vessel the lauter tun, where the mash is strained and rinsed over a false bottom to extract the sweet wort for fermentation.” The word is derived from the French word for copper, cuivre, pronounced “kweev.” McGovern says the Irish just like to be different.
The sweet wort is piped to the next level down, the coppers. Fabricated of stainless steel, these boilers are copper only in name. The brewers boil off 10 percent, to a total of 1,200 hectoliters (about 1,000 barrels, or 31,000 gallons). The brewhouse has three coppers and three upperbacks, vessels used for temporary storage of sweet wort in the event no boilers are available. Coppers and upperbacks are essentially of the same design. However, the upperbacks do not have boiling equipment attached.
Guinness boilers employ the external boil “Calandria” method, where heat is transferred to wort by a bundle of steam pipes in one small area, where the wort is heated to boiling, then pumped in circulation through the kettle. The heat is not actually applied to the kettle. Because they are so huge, it would be challenging and inefficient to heat the kettles directly. McGovern likes the Calandria system because it is fast and furious. “Our boilers get the wort going quickly and keep it at a very vigorous, rolling boil, which is key to making good beer.”
Guinness Stout is hopped only once, in the kettle, with a blend of hops. About 100 kg (220 pounds) of hop pellets are added at the start of the 90-minute boil. Depending on season and availability, Guinness may contain Nugget or Galena from the Yakima Valley, Northern Brewer from Germany, Pride of Ringwood from Tasmania, Kent Goldings from England, and other varieties from other regions.
After boiling the hops are strained out, the wort cooled, and more than 500 pounds of yeast is pitched as the wort makes its way to one of the brewery’s several dozen outdoor stainless cylindro-conical fermenters. Fermentation is warm and fast: 48 hours at 25° C, or 77° F, using a strain of yeast descended directly from that used by Arthur Guinness.
The fermenters tower like silver sentinels, standing in groups around the brewery complex. They come in several sizes, the largest big enough for one 1,200-hectoliter (31,700-gallon) batch. After primary, the beer goes to centrifuge for yeast removal, and isinglass finings are added for clarification. Then it goes to another waiting cylindro-conical for secondary fermentation, which the Guinness brewers refer to as “maturation.”
The secondary ferment is important to the final product. Guinness Stout is kraeusened in the secondary. That is, blended with gyle (unfermented wort) and a little yeast to set up natural carbonation. No Guinness is artificially carbonated. Nor is it filtered. When you get right down to it, Guinness is made a lot like homebrew, only on a mammoth scale.
The maturation and conditioning period lasts 10 days. From there the beer is carefully blended with previous batches until the brewers are satisfied that the proper flavor balance has been reached. Only then is the product released to the keg lines or to bulk transport.
The Old and the New
Until 1988 all the transfer of wort and beer was completed manually by men turning huge hand-crank valves in the Dublin facility’s “storehouse,” built in the 1870s and fitted with cavernous square aluminum fermenters in the 1950s.
The storehouse is still there but only collects dust these days. The building is red brick on the outside, iron, tile, and concrete on the inside. Overhead runs a maze of pipes, tubes, chains, and pulleys. Narrow corridors wind their way between the fermenters and pump stations, where hundreds of men once trotted from pump to pump, valve to valve, getting the beer from one vessel to another.
The tools of their trade are still there, custom made for the big square fermenters and now useless. Dipsticks, paddles, and other gadgets, they hang, seemingly at the ready, inside large rusting steam chests.
Production manager McGovern himself spent the first half of his Guinness tenure in the old storehouse, before modernization made it obsolete. “Before anything was dipped in the wort, it was sterilized by steam in the big chests,” he explains.
Making beer this way was somewhat inefficient and very labor-intensive. Everything was done by hand with the manual valves and pumps. The fermenters were flat-bottomed. Once they were drained, men had to climb inside and shovel out the sediment. Then workers with hand-held steam guns sterilized the whole place, standing on the bottom.
The fermenting tanks are nothing short of mind boggling. The larger ones can each hold 26 double-decker buses. Today, they sit idle, dusty and dark, disturbed only by the occasional visitor. It’s hard to resist sticking your head in the manway and yelling “Hello-o-o-o.” The echo lasts a good 10 seconds.
McGovern opens a locker to uncover a grid of pegs, each labeled with a number. “The valve keys were stored here. Each valve was numbered, with a lock on it. Each key number corresponded to a valve. When we wanted to move some beer, first one man devised the plan. That was checked by another man and approved. Then the valve keys were distributed and the valves unlocked.
“Each valve was checked by another man and approved. Finally, when the manager gave word, the valves were opened and the pumps switched on to move the beer. Even with all the checking and cross-checking, we still lost a fair amount of beer. It was quite a challenge to keep track of it all.”
McGovern’s valve story is a graphic example of what prodded the brewery managers to look at modernization in the 1970s. The brewery managers realized that the art of brewing had progressed beyond the Dublin plant’s design. Clean-in-place stainless steel was the wave of the future and automation was on the horizon. A near total transformation in process was in order. To date the firm has invested some £200 million (about $300 million) in new technology and equipment.
The new brewhouse has capacity to brew 16 batches every day. On average four batches per day are produced, a total of more than four million pints.
The new FBP, Fermentation and Blending Plant, is an orderly, sparkling-clean web of stainless pipes, tile floors, valves, drains, tanks, and automatic pumps. The place hums loudly, and workers there wear earplugs to protect themselves from the din of machinery.
Under the FBP the bottoms of the outdoor cylindro-conical tanks pierce the ceiling at regular intervals. Each is surrounded by a nest of pipes, manifolds, and remote-control valves. Brightly lighted and with a white tile floor, the FBP is operated from afar by the brewers in the control room. Being there is like being inside a leviathan, living creature. Valves open, vents are released, pumps switch on and off. It is an industrial symphony of clanging, whirring, hissing machinery performed in three-dimensional living sound.
The beer makes its presence known by its distinct aroma. But sometimes the product is less subtle. An occasional, short-lived river of dark, foaming stout rushes down a floor drain, the last remnants of a tank being emptied or overflow from cleaning. It’s a strange and wonderful place.
Above, protected from the noise by a wall of glass, sits the modern brewer. Gone are the rubber boots and coveralls. Today’s brewmasters sit in climate-controlled comfort, clad in jackets and ties, overseeing a dizzying array of computer terminals, protocol notebooks, and an amazing wall of blinking LED indicators and lights.
Two such control rooms are where the action is at today’s Guinness plant. The smaller is where brewers oversee wort production and boiling in the brewhouse. The larger, more spectacular room is in the FBP. A curved schematic diagram stretches from one end of the room to another, adorned with flashing lights and LEDs. The entire brewery process, from mill to keg to cleaning, can be ascertained with one glance at this diagram.
Every valve, every tank, every vent is interfaced with the computers. Procedures are completed almost effortlessly, with little resemblance to the days of sweat and grime spent by brewers of yesterday.
Keeping It Perfect
The brewery’s impressive array of advanced technology does not make beer by itself. The machines cannot monitor quality, either. That job requires a human touch.
If the beer made at the Dublin brewery has a pulse, Norman Kinsella is the man with his finger on it. As director of quality assurance, Kinsella knows the beer intimately. He pokes it, prods it, cooks it. He takes it apart and puts it back together again, all in the name of quality. You might say he is a little obsessed with quality.
“There’s a certain mystique, a sort of folklore attached to this beer, especially at this brewery,” Kinsella says, ever mindful of the palpable presence of Arthur Guinness’ historical legacy in Dublin. “That goes a long way in terms of image, character, and interest in the marketplace. But it only goes so far. What really counts is the beer itself. We can’t lose sight of the fact that every pint, can, and bottle has to be as good as it can be, and that takes effort,” he explains.
You might say Kinsella is mad about Guinness, or at least head over heels for it. He’s an animated, fast-talking, serious-looking guy who puts his heart into his work — and into talking about his beloved stout. He has an intense look in his ice-blue Irish eyes. He’s serious about something most of the world takes with a grain of salt, the humble barley drink.
“We’ve got to be on top of the product long after it leaves the brewery, because the way it’s stored, handled, and dispensed in the market can wreak havoc with the quality in the glass.
“You know, we still occasionally find a pub dispensing beer with compressed air. That’s absolute madness! An invitation to oxidation and trouble. We’ve got to worry about the publicans cleaning their beer lines, how they store the beer and serving it at the proper temperature, using the right gas to dispense, keeping the glasses clean. And we’re doing it.”
The Taste Test
Kinsella’s crew employs a large arsenal of weapons in their fight against contamination and infection, including a brewery-wide quality assurance computer system. But computers can’t taste Guinness. For that Kinsella holds court in the Guinness sample room. Tastings are important events at the brewery. Informal tastings go on all the time. And organized tasting panels convene once a week or so.
Kinsella explains that the QA team is careful to gather opinions about the beer from people within the brewery, but not just beer people. He has assembled a tasting panel that puts world-class brewers shoulder to shoulder with clerks, drivers, engineers, senior managers, and myriad other employees from all walks of life.
“The most basic research goes on right here in the sample room. You don’t have to be a professional taster to join the panel and express your opinion about the beer. That’s because the men and women who drink it out in the pubs are not professional tasters, either. But they know what they like and don’t like,” says Kinsella.
The sample room is something out of a beer-lover’s fantasy: clean and bright, with technicians clad in white lab coats pulling miniature pints, small glasses shaped like the traditional Dublin pint jar. Dozens of shining taps stand at the ready. The beer is as fresh as it can be, dispensed at optimum conditions of temperature and pressure.
And boy, is it tasty.
“We rate the beer according to a scale of five. Five is perfect, few ever get that grade. Four is about the best we ever give, three is very good. Anything below three is defective and will not be released. Even though a beer rated below three in here might be very drinkable, it’s not good enough to be sold,” Kinsella explains.
Nitrogen. It’s a Gas, Man
Certainly one of Guinness’ strong suits is its amazing, dense, creamy head. Around the brewery employees pay a lot of attention to the art of producing it properly. It’s a home-grown effort. In fact Guinness people call its creation “the Dublin Dispense.” What they mean, of course, is dispensing the beer, from draft or draft-can, charged with a mixture of nitrogen and carbon dioxide.
No other beer has a head quite like Guinness. It’s a masterful invention of modern scientific thought, coupled with traditional techniques of production. Every time the classic Guinness head rises on a glass of draft Guinness pulled anywhere the world, it can be traced to three basic roots: raw barley in the mash, famous for its head-enhancing abilities in any beer; natural conditioning in secondary fermentation; and using nitrogen as a component of the beer’s dispensing gas.
Anthony “Tony” Carey is one of the Dublin brewery’s great scientific minds. Director of technical development, he has called Guinness home for 32 years, since graduating from the natural sciences program at Cambridge.
Carey has worked on a gunnysack full of interesting projects in his 32 years at Guinness. But one project holds a special place in the hearts of Guinness lovers. Carey is the man behind the widget: the inspired design of the draft-can system. He proudly displays the patent, granted in 1979, with his name at the top — along with other, now retired Guinness scientists.
Carey is quick to point out that the success of the draft-can is the result of many men and women working for years on its development. It just so happens that he invented it.
The draft-can is the latest in a line of gadgets designed to recreate the special creamy Guinness head, away from the pub tap and in more exotic markets outside Dublin. Some of these gadgets met with limited success. Some were failures. But each has at its heart a common element: nitrogen. That’s the real secret behind the head. A trick that was discovered by an anonymous publican, quite by serendipity.
Carey explains in his elegant English accent. “We don’t know his name. Perhaps it’s best that way, more legendary. In any event Guinness used to be cask conditioned, like English real ale. But some of the publicans had trouble with the beer when it got too lively, too foamy,” he says.
“As is so often the case, inspiration comes at the interface between product and customer. This enterprising publican kept the cask conditioning going but vented the cask to relieve pressure. He then devised a compressed-air system to dispense it. The head on his beer was denser, thicker, and creamier than his competitors. It was the nitrogen in the atmospheric air, dissolved into the beer, that made the difference,” Carey explains.
By the 1960s most Dublin pubs were using the compressed air system. But at some cost. Oxygen in air, as all homebrewers know, spoils beer. To solve that problem, Guinness pioneered the use of the nitrogen/carbon dioxide mix in all their kegs and pub dispense systems. Guinness kegs are charged with 80 percent nitrogen, 20 percent CO2 for the European market and 75 percent nitrogen for the US market. The difference is because it’s stored colder in the US. Guinness is dispensed from half-barrel kegs at between 30 and 40 PSI pressure.
Perfecting the Can
Tracing the lineage of the draft-can, Carey flips through a book of pictures representing technological steps along the way. He also occasionally walks to his office marker-board to diagram a particular point about atmospheric pressure and bubble half-life. This guy really knows beer foam.
Previous draft designs include a disposable beer syringe that was supplied with six-packs of Guinness Bottle Draft. The consumer had to pour the beer, suck up a little in the syringe, then shoot it back into the glass. This introduced air and seeded a thick layer of creamy bubbles. Carey digs out a bar-mounted version of this device, which is still in use in at least two markets: Japan and Nepal. Another was the bar-mounted ultrasonic initiator, which held a full glass of Guinness and used ultrasound to seed the bubbles. “Both ideas worked but were economic failures. Just a little too clumsy to be widely accepted in the marketplace,” says Carey.
When asked what is on his and his colleagues’ current drawing boards, he replied: “Now that the draft-can system seems to be holding its own, we are very interested in developing a similar system for returnable bottles. If any of your readers have invented such a system, we would love to hear from them!”
The Spirit of Guinness
“One of the secrets of Guinness’ success is an ethereal, mystical component of the beer: the commitment of the people who make it,” says Carey.
Even the youngest college grads, trained in chemistry, engineering, and industrial management show deep respect and reverence for tradition — knowingly or not — when they make Guinness Stout.
That’s because one thing hasn’t changed at the Dublin brewery: the beer. Only minor modifications have been made to the recipe over the years. It’s still unfiltered, unpasteurized. Still naturally carbonated the old-fashioned way. Still made from the most basic of raw materials.
John O’Sullivan, the Dublin brewery’s manager of kegging and warehousing, puts it quite succinctly: “At the end of the day, it’s the beer that makes or breaks us. People aren’t stupid. They know good beer when they taste it. That’s what keeps us on our toes. Keeps us doing it for real, not just talking about doing it.”