BREWHOUSES

The Huppmannbrewhouse at OettingerBrau in Germany hasbeen installed within ano frills industrialbuilding. Oettinger is aleading supplier to thesupermarket trade.

1The BREWER & DISTILLER • Volume 2 • Issue 2 • February 2006 • www.ibd.org.uk

Mention building a newbrewhouse and anybrewer’s eyes light up andthe ‘red mist’ descends atthe thought of gleamingshiny vessels in a marblehall set off with murals ofmalt and hops andmodern lighting effects.The reality is often quitedifferent and a lot ofthought, analysis and soulsearching have to bedone before the dream isrealised.

This article is written by apractical brewer and is not

intended to be a thorough analysis ofeach item of equipment, but willlook at the things anyone building anew brewhouse should consider.Brewhouses are expensive, basically

permanent, and any fundamentalmistakes very difficult and certainlycostly to rectify.

From the brewer’s perspective,there are five key requirements inspecifying a new brewhouse – theseare:a) Brand image.b) Capacity – how big should it be?c) Wort and beer quality – taste, head

retention, flavour and hazestability

d) Capital costs – plant choice anddesign.

e) Running costs – brewhouse yield,raw materials energy costs, manningand other costs.

Brand imageIt is important that a company takesinto account its brand and imagewhen developing a new brewhouse.If beer quality and tradition is coreto a brand image – particularlypremium brands, then positive PRcan be gained from a ‘showpiece’brewhouse, but if a company is morecommodity based, leading withprice and does not have strongindividual brands, then a different

approach can be made. With brandimage and strength becoming moreimportant, how many companiesregret building functionalbrewhouses? After all, customersexpect to see more than a ‘chemicalplant’ when they visit the ‘home’ oftheir favourite beer. It does notalways cost a fortune to make abrewhouse ‘smart’ instead of purelyfunctional (Fig.1)

Brand image may not onlyinfluence the look of a brewery, butalso dictates the raw materials andprocesses used. In designing a newbrewhouse, there must be a seriousdebate on the recipe of a beer,because this will decide the plantchoice and the final cost of theproject.By Paul Buttrick

Beer Dimensions

A brewer’s view on a modern brewhouse project

Figure 1: A ‘showpiece’Ziemann brewhouse at aLatin American brewery.

Pho

to:R

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Put

man

.

“The decision bySAB-Miller to retainthe triple decoctionprocess, a copperheat exchangesurface, and directgas firing for PilsnerUrquell is no doubtthe result of adebate that puts thebeer and traditionalprocess used at theheart of the imagedemanded by thisunique beer.”

BREWHOUSES

The decision by SAB-Miller toretain the triple decoction process, acopper heat exchange surface, anddirect gas firing for Pilsner Urquellis no doubt the result of a debate thatputs the beer and traditional processused at the heart of the imagedemanded by this unique beer.(Fig.2)

How big should a brewhouse be?The normal way to size a brewhouseis to take the peak weekly ormonthly volume of the business anduse this as the basis for the capacitycalculation. It is also important toinclude an overall efficiency factorfor the operation which wouldinclude plant cleaning, mechanicalefficiency and other non-productiondown time. Extra capacity can thenbe added to take account of futurevolume growth. This can be done byleaving extra days or shifts availablefor peak working, e.g. five and sevenday working, double or triple shiftworking or a planned option todecrease brew cycle times.

A single brewery company willtake a different view to aglobal/national one with a number ofbreweries. With multi breweryoperations, the capacity andcapability of all the breweries must

be taken into account, as is thedecision about which plant is to beexpanded. In these situations, anoverall production and minimumcost sourcing exercise needs to bedone to get the right economicanswer, before taking other factorssuch as local marketing conditionsand risks into consideration.

The planned brew length willnormally be dictated by the size ofother plant in the brewery –especially fermenting vessels.However – the opportunity shouldbe taken to review both brewlengthand brewing gravity, because it willaffect the capacity of the wholebrewery. It is important in thisexercise to make sure everything‘fits’ and not get a mismatch ofvessel size and brewlength – e.g. a500 hl brewlength with 5000hlfermentation vessels or a 1000hlbrewlength with 300 hl vesselswould not be ideal. It is alsoimportant to ensure that yeastpitching can be properly managed.

Brewers always like to build inflexibility, but at what level does thisbecome uneconomic? Somebreweries that are based on a twostream brewhouse, should considerwhether a single stream plant is abetter option. A single stream will beless complex, less costly to install,easier and more economic to run.

Raw materials The beer recipe can significantlyinfluence the capital cost of abrewhouse, and its effect on ongoingbrewing costs. The degree of maltmodification dictates wort and beerquality as well as brewhouseprocesses. In traditional lagerbrewing, under modified malt isprocessed using a decoction system,with mash boiling vessels being keyplant items. Many breweries areusing temperature programmedmashes and some employ infusion

mashing to produce lager wort.Current opinion and experiencesuggests that reducing the length andintensity of mash heating and copperboiling results in beers withimproved flavour stability – little didale brewers of the last century realisethat they were at the forefront of 21stcentury brewing science!

Malt is the main raw material, butadjuncts play a big part in dictatingbrewhouse plant and costs. Forexample, the use of un-gelatinisedmaize grits requires the use of acereal cooker, but using flaked maizedoes not. Similarly, use of liquidsugar requires storage tanks, butdoes not take up conversion vessel orwort separation equipment capacity.Maize grits are less expensive thanmaize flakes, liquid sugar is thesame cost as malt. Doing an exerciseweighing up the cost of extra plantand complexity against raw materialand energy cost needs to be carriedout.

Remember that cereal prices varyfrom year to year, so a spotcalculation on a single year is notwise. The result of this can lead to abit of soul searching and wisedecision making on behalf of thebrand owners (more often than notthe Marketing function who mayhave to manage the PR aspects ofany recipe or process changes.

Many people underestimate thepart that hops play in beer flavour andquality, therefore the choice of hopproducts is important. Extractsproduce a clean beer with little hopflavour or aroma and are easier toprocess due to less bulk; wort lossescan be up to 1% lower than whenusing hop pellets. Hop pellets givemore polyphenol content to wort andif added late impart aroma and hoppyflavour. Polyphenols add to theoverall mouth-feel and body of thebeer as well as improved flavourstability, but if in excess can detract

2The BREWER & DISTILLER • Volume 2 • Issue 2 • February 2006 • www.ibd.org.uk

Figure 2: PilsnerUrquell brewhouse

(2004). Note the copperclad vessels with one oftwo 10m lauter tuns inthe back ground. Over

100,000 visitors a yearinspect this view from an

elevated walkway.

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to:R

oger

Put

man

.

RIGHT: Figure 3:Equipment schematicfor “wet” and “dry”

milling operation –diagram from

Huppmann

FAR RIGHT: Figure 4:The “Dispax” milling

system in a Dutchbrewery– photo

supplied by Ziemann

“The beer recipe cansignificantly influence

the capital cost of abrewhouse, and its

effect on ongoingbrewing costs. The

degree of maltmodification dictateswort and beer qualityas well as brewhouse

processes. Intraditional lagerbrewing, under

modified malt isprocessed using adecoction system,with mash boilingvessels being key

plant items.”

3The BREWER & DISTILLER • Volume 2 • Issue 2 • February 2006 • www.ibd.org.uk

from haze stability. Hops whetherfrom pellets or leaf are known toimprove the quality of beer foamcompared with beers brewed usingextract.

The correct choice of plant willinfluence the overall project cost,beer quality and how much it willcost to brew for the next 20 years ormore. With energy and waste costsrising, these will have an increasinginfluence on running costs. Thelatest techniques involving reducedwort oxidation and ‘thermal stress’are also leading to improvements inflavour, flavour stability and headretention.

Thermal stress is brought aboutby any process involving excessheat at high temperatures in anybrewhouse process (eg excessivewort boiling) Over enthusiasticmixing in other brewhouse vesselssuch as conversion vessels also hasa negative effect on flavour stability.The leading brewhousemanufacturers all offer their owninterpretation and development onthe latest available brewingknowledge and science.

MillingThere are three main options formilling. Dry milling normally usessix roller mills and is still popularwith breweries using lauter tuns.The milling is independent from themashing process and therefore alower rated mill can be used so thatthe milling operation can utilise theconversion vessel cycle-time,whereas ‘continuous steep’ millingrequires milling to take place in 20minutes of the mashing process. It isalso reckoned that mill adjustmentsavailable on the three sets of rollersgive a better opportunity foroptimisation of extract and run off.

Hammer milling is only used inconjunction with the mash filter in

order to get the 30% fine flourrequired, power consumption is upto three times that required by wetmilling systems. Noise andexplosion risks also need to be takeninto consideration.

Continuous steep milling isrecommended by Steinecker(Variomill) and Huppmann(Millstar) and can be used inconjunction with any lauter tun.Conditioning of the whole maltgrain in a continuous warm watersteep increases the water content ofthe husk to approx 15 % beforemilling. Advantages over drymilling are said to be better andfaster wort separation withopportunities for increased lautertun loading, less equipment and lessexplosion risk (no dry ground grist),less oxygen uptake due to mashingtaking place at the same time asmilling (Fig.3).Ziemann have recently developedtheir innovative “Dispax” dispersionmashing/milling system which is acompact ‘wet’ option mainly for usewith mash filters (Fig.4)

Mash ConversionThe key here is the choice ofinfusion/temperature programmedmashes and whether mash boilingand cereal cooking are part of thedesired brew recipe. Allmanufacturers feature on lowoxygen pick up, efficient mixing,heat transfer with latest designmixers and temperature control.Ziemann and Steinecker(ShakesBeer) have introduceddimpled heat surfaces inside thevessel (Fig.5) which gives improvedheat transfer and hence fastertemperature rises for programmedmashes. Along with hot waterinjection, heat rises of over 2°C/minas against 0.5– 0.9°C/min for aconventional conversion vessel can

be achieved. This would beimportant to any brewery whosemash cycle is the rate determiningstep in their brewhouse. For atemperature programmed mashstarting at 45°C and rising to 75°C,an overall time saving of 30–50minutes is very significant. Notethat any operation using mashboiling or decoction will includemore complex plant as well asincreased energy costs.

Wort separation The big debate continues on the useof lauter tuns and mash filters. Historically mash filters had a briefrise in the late 1970s, butimprovements in lauter tun designreasserted their ascendancy until theintroduction of the Meura 2001membrane mash filter (Fig 6).Ziemann continue to offer modernmash filters and lauter tuns. TheZiemann TCM (Thin layer ChamberMash filter) produces up to 16brews per day, the largest versiontaking a 21 tonne grist. At presentthere is no clear winner, except thateach brewer must make the decisionbased on its own requirements.Breweries using unmalted adjuctsand high gravity brewing often optfor mash filters, as do brewerieswith a low number of wort streamsrequiring fast throughput and highextract yields. Lauter tunmanufacturers, Briggs, Ziemann,Steinecker (with Pegasus) andHuppmann (with Lauterstar) havecontinued to develop theirequipment to increase loading (upfrom a “norm” of 160kg/m2 to over200kg/m2) while reducing cycletimes and increasing extract. Anemphasis has been put ondecreasing down time (like spentgrain removal) with improvementsin rake design, automated rakingand run off control improving the

Photo:R

oger Putm

an.

Figure5: The dimpledsurface on ShakesBeerconversion vessel –photo supplied bySteinecker

Figure 6: One of twocentrally-fed 16 tonneMeura 2001 mash filtersinstalled at InBev’sMagor plant in SouthWales.

“Continuous steepmilling isrecommended bySteinecker(Variomill) andHuppmann (Millstar)and can be used inconjunction with anylauter tun.Conditioning of thewhole malt grain in acontinuous warmwater steepincreases the watercontent of the huskto approx 15 %before milling.Advantages over drymilling are said to bebetter and fasterwort separation withopportunities forincreased lauter tunloading, lessequipment and lessexplosion risk (nodry ground grist),less oxygen uptakedue to mashingtaking place at thesame time asmilling.”

BREWHOUSES

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wort flow itself. A significant stepforward has been to increase thenumber and positioning of run offports incorporating a conical design(Fig.7). This has resulted in fasterrun off with an even extractrecovery across the whole bed andless vacuum produced.

Without getting into detail, themain differences between a lautertun and mash filter include thefollowing. The lauter tun is moreflexible for loading – charges of +50% to -30% are claimed with themash filter only able to handle+10% to -20% of optimum loading.Smaller breweries with a largenumber of beer brands are morelikely to favour lauter tuns becauseof this.

The cycle time of the mash filterof 90–120 minutes has beenconsistently better than the lautertun, although using the latest run off

technology twelve brews per day ona bed loading of 200 kg/m2 can beachieved with a lauter tun. Whatevermash separation device is used, themalt quality is vital to goodperformance, especially levels ofbeta glucans, with β-glucanaseaddition to the mash often used tomaintain consistent run offperformance on mash filters.

A recovery of 100–101% oflaboratory extract from a mash filtercompared with say 98.5% on anoptimised lauter tun can mean asaving in malt of around £150,000per year at a brewery producing onemillion hectolitres of wort. There is,however, a debate about how muchthe extra 3–4% extract is of positivevalue from a beer flavour andquality perspective.

Capital costs of lauter tun systemsare claimed to be about 70% of anequivalent mash filter. Themaximum size for a single mashfilter has been around 11 tonnes ofgrist (approx 600 hl of high gravitywort) compared with up to 25tonnes for a single lauter tun,although the 21 tonne Ziemannmash filter is catching up fast.

Operating costs for mash filtersare also higher. This is mainly dueto higher maintenance costs,cleaning costs (cleaning requiredevery 50–60 brews), replacement offilter sheets (every 2,000–3,000brews) and membranes (every 5,000brews). Unlike the Meura 2001, theZiemann TCM has no membranes tomaintain or replace.

Wort BoilingAs energy costs rise, wort boilingwill continue to be an area ofincreased attention. Modernunderstanding of wort boiling hasenabled manufacturers to look atwort volatile reduction and proteindenaturisation/ coagulation asseparate processes. The idea ofapplying a minimum temperaturedifference between the heatingmedium and the wort by effectivelyincreasing heating area andinducing two phase liquid/vapourbubbles in the wort means that wortevaporation can be reduced fromover 8% to 4–5%. Differentapproaches have been made bymanufacturers, with some opting fora separate volatile reducing stepafter wort boiling.

Beers produced have similarfermentation characteristics andvolatiles as well as reduced DMSlevels. Reduced thermal stress on

the wort also predicts an increase inflavour stability, although resultssupplied by manufacturers aredifficult to assess and comparebecause they are often from differenttests and analyses. With flavourstability and beer freshnessattracting more focus, relying moreon tasting beer and using betterunderstood analysis would behelpful. Reduced evaporation fromless and lower heat input also resultsin improved beer foam. Less foulingof the heating surface also has thebenefit that cleaning frequencies canbe reduced. The introduction of anatural thermosyphon duringboiling is becoming a feature in allmodern wort boilers.

There is a choice between internaland external wort boiling. The latteris a development of Briggs externalwort boiling system and is called‘Symphony’ (Fig.8) This involvesincreasing the specific heatingsurface of the boiler to 0.43m2/hlwhich is five times more than for atypical internal heater, and twice ashigh as a standard external wortboiler. By using this increased area,the steam temperature and pressurecan be reduced and a two phase,liquid/vapour driven thermo-syphonis produced. The wort, which iscirculated eight to ten times duringthe boil, is returned to the copper ina tangential manner to reducefoaming and minimise trub breakup. This arrangement of externalwort boiler and tangential inlet tothe copper is easily arranged into acombination copper/whirlpool.

Other suppliers have developedefficient internal copper heaters. A‘dynamic’ or ‘low pressure’ boilingtechnique has been introduced byHuppmann (Fig.9) which involvesheating wort under pressure of 150mbar, equivalent to a boilingtemperature of 103°C. When thispressure is reached, it is rapidlyreduced to 50mbar and thetemperature drops back to 101°C.This takes place at least six timesduring each boil and the effectproduces a flash evaporation withthe formation of foam and bubbleswithin the wort kettle which stripsunwanted volatiles and aidscoagulation of hot break particles.In order to accommodate the flashevaporation, the copper volumeneeds to be 30% greater than for astandard system and the wort iscirculated 20–30 times per hour.

Ziemann offers a similartechnology. The internal wort heater

Figure 7: The undersideof a modern lauter tun –take note of the number

of wort run off pipes –photo supplied by

Huppmann

Figure 8: The Symphonyexternal wort boilingsystem – supplied by

Briggs of Burton.

Figure 9: Thetemperature/pressurechart of “dynamic/lowpressure boiling”process – supplied byHuppmann.

5The BREWER & DISTILLER • Volume 2 • Issue 2 • February 2006 • www.ibd.org.uk

as applied by Steinecker(Stromboli) creates a large heatingsurface within an internal heaterwhich enables wort volatile removaland precise protein coagulation atlow thermal load. The heater has aspecially designed two part spreaderfor the heating and boiling part ofthe cycle. A natural thermo-syphonvia a “jet pump” above the centraltube enables the heat input to bereduced(Fig 10,11) As with theBriggs Symphony system, foulingof the heater is reduced, resulting ina lower cleaning frequency( Fig12,13) Huppmann introduced aninternal heater with a naturalthermosyphon called Jetstar inSeptember 2005.

Volatile stripping from wortafter boiling German manufacturers havedeveloped equipment to improveenergy efficiency, beer quality andflavour by stripping volatiles afterthe copper. This allows copperevaporation to be reduced to 3–5%.DMS and precursor reduction takesplace after the copper, but beforewort cooling.

The Steinecker system, called‘Merlin’ is a vertical cylindricalvessel with a steam heated, conedshaped interior over which a thinfilm of wort is pumped before itgoes the whirlpool (wortevaporation is 1–2%) (Fig.14).Ziemann offers a different approachusing a vacuum technique workingat approximately 0.4 barunderpressure to strip out volatilesbetween whirlpool and wort cooler(Fig.15).

Energy saving and wortboilingWith UK gas prices reaching a peakof £1.40 per Therm (£0.013/MJ) inNovember 2005, the requirement tosave energy moves from a financial“nice to do” to a definite “must do”.It would be sensible for any brewerto look at retrofitting energy savingequipment whether or not a fullbrewhouse development is beingconsidered.

Brewers should be as focussed onenergy usage as they are on maltextracts. Large energy savings arepossible, especially if energyrecovered from a vapour condenseris used for preheating wort going tothe copper. This technique involvesinstalling an energy storage system,which comprises a hot water storagetank and heat exchanger for taking

FAR LEFT: Figure 10:The “Stromboli”internal copper heatingwort up to boilingtemperature. –

LEFT: Figure 11: The“Stromboli” internalcopper heating systemin boiling modeincludingthermosyphon.Diagrams supplied bySteinecker.

FAR LEFT: Figure 12:The tubes of aconventional internalwort heater after 8brews.

LEFT: Figure 13: Thetubes of a Stromboliinternal wort heaterafter 80 brews – noticehow the less intensiveheating regime hasreduced foulingconsiderably. Photossupplied by Steinecker.

Figure 14: The invertedheating surface cone ofa Merlin boiling/ wortstripping system seen inan exhibition mock up –photo supplied bySteinecker.

BREWHOUSES

6The BREWER & DISTILLER • Volume 2 • Issue 2 • February 2006 • www.ibd.org.uk

wort from approx 75°C after thewort separator to 95°C+ in thecopper (Fig.16).

Trub separation The whirlpool remains the mostpopular and simplest method forseparation of hot trub from boiledwort. The workings of whirlpoolshave been studied extensively withmany theories and calculationsshowing the best design. A vesselheight to diameter ratio of around0.5, copper casting time of tenminutes, tangential inlet velocity of3–4 metre/sec and stand time of 20minutes normally works effectively.

An often overlookedconsideration is solids loading. Inorder to get good trub separation, itis said that hop pellet loading shouldnot exceed 2.0kg/m2. Hop pelletsalso retain extract, so increasing ordecreasing hop pellets and hopextract ratios can make a differencein yield. There are many designs forthe run off system, floor shape, andtrub removal, all of which areimportant to consider as long as thebasic design gives a good result.Converting hop backs in traditionalbreweries to effective whirlpools isoften easily achieved with minimalexpenditure.

Combined copper-whirlpoolshave been successfully installed inrecent years, these tend to be acompromise in optimum design,Vessel configuration and the hopgrist must be fully considered alongwith all other criteria. An advantage

of a copper whirlpool is that a vesselto vessel transfer is eliminated, thereis less trub particle size reduction,and it allows a faster start up ofwort transfer to fermenter. Thecopper/whirlpool is a naturaldevelopment from the BriggsSymphony system involving atangential inlet to the copper and isbranded as ‘Symphony Plus’

A final word It is easy to get carried away withnew plant, but a dedicated projectteam and detailed planning needs tobe in place from the beginning.Bringing the new plant on stream isnot always as straight forward asfirst thought and a logical step-wiseprogramme of trials to ensure beerflavour and quality match thespecifications is fundamental.

There should also be acomprehensive blending operationin place until all ‘stakeholders’ aresatisfied with the result. It isimportant that the Marketing andSales functions are included in thisprocess and the success criteria fora successful flavour match is agreedbeforehand, so there is no disputewhen the time for the final sign offcomes. ■

● The author would like to acknowledgethe help of the following for supplyinginformation, diagrams andphotographs for this article.Briggs of Burton (PaulDowd), Krones/Steinecker (PeterGattermayer), Huppmann (ThomasBühler) and Ziemann Group (VolkerMewes).

Figure15: A Ziemannvacuum wort

“stripping” systempositioned after the

whirlpool but beforewort cooling – photosupplied by Ziemann.

● The author

After a long career with Whitbread andInterbrew, including time as Head Brewerof Boddingtons and Stella ArtoisBrewmaster, Paul Buttrick has startedhis own independent consultancy BeerDimensions. Paul has an MSc in BrewingScience from Birmingham University andis one of only a handful of British brewersto have studied at Weihenstephan (T.U.Munich).

Figure 16: Schematic of a brewhouse ‘energy store system’, with heatrecovered by a vapour condenser used to preheat wort on its way to the copper– diagram supplied by Huppmann.

Operation Approximate Cost per 1 million hl per Therm Cost per 1 million hl brewed withEnergy usage brewed with gas cost at £0.65 gas cost at £1.4 per ThermMJ/hl (£0.00616 per MJ) (£0.0133 per MJ)

Wort pre-heating 12 £73,900 £159,200from 75°C to 95°C5% wort evaporation 12 £73,900 £159,20010% wort evaporation 24 £147,800 £318,400

TABLE 1Table 1 shows the orderof magnitude of costs for

wort pre-heating andboiling for a one million

hectolitre brewery(volume brewed) at both

5% and 10%evaporation as the cost

of fuel doubles.

“It is easy to getcarried away with

new plant, but adedicated projectteam and detailedplanning needs to

be in place from thebeginning. Bringing

the new plant onstream is not always

as straight forwardas first thought anda logical step-wise

programme of trialsto ensure beer

flavour and qualitymatch the

specifications isfundamental.”

7The BREWER & DISTILLER • Volume 2 • Issue 2 • February 2006 • www.ibd.org.uk

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