CHAPTER 4

The Brewing Process

For the most part, the steps and the equipment employed in brewing barley wines are the same as those required for brewing other British ale styles. The difference lies in the technique used for each of the steps. Brewing a barley wine requires extra vigilance and extra attention; unless you make the commitment to brew nothing but barley wines and other big beers, and thereby devise systems and procedures that eventually settle into second nature, the brewing of these biggest of beers is likely to require extra work and craft. The whole brewing process must always be considered as one of continually making procedural decisions to adjust the enterprise along the way. The question to remember is how can you get that much more of everything out of your brewing system?

Milling

Time was, brewers were also maltsters, and needed to be concerned with every aspect of procedure connected with the processing of raw grains. Nowadays, of course, nearly all brewers receive their grain already malted, and while pre-delivery specifications and procedures need to be maintained, all that really has to be done to prepare for mashing is to crack or mill the malt.

The milling (cracking open) of the grain exposes the starch, or endosperm, which subsequently will be converted to sugar in the mashing process. This cracking or grinding of the malt is accomplished by means of a roller mill. Roller mills are adjustable to allow for the size variations inherent in different types of malt. Herein lies the rub: the husk of the grain must be cracked open without pulverizing the whole kernel. It is very important not to overcrush your malt. This is true with the brewing of any beer but especially true with barley wines. Barley wines, in fact, can use two to four times as much malt as an average brew, resulting in a greater bed depth in the lauter tun and thus much higher screen pressures. On a good day, a barley wine runoff can take fifteen to forty-five minutes longer than a usual brew, but an overly crushed malt will cause the mash bed to become compacted. It can gum up, slowing the proceedings to a trickle, and eventually stick your runoff completely, turning your brewing day into a living hell, or at least a major bummer. In addition, small chunks of husk can be sucked through the lauter screens, carried over to the kettle and, when boiled, result in unrefined grain flavors and harsh, astringent bitterness. All of these reasons make it very important to properly mill your malt.

If you are a professional brewer, control lies as close as the adjusting screw on your malt mill. But if you are a homebrewer at the mercy of the milling facilities of your local homebrew supply shop, try to make sure their mill is set properly to not overly crush the grain. If in doubt, ask to see a sample first. Sure, the shop person may think you’re being a beer geek, but so what? They won’t be the one dealing with a stuck runoff if the mill is set too tight.

The Brew House

The traditional British brew house has two main vessels: the combination mash/lauter tun and the kettle. In some cases it may also have a hop back (strainer) or, if a modern brewery, a designated whirlpool for the separation of hops and trub.

The Mash Tun

In many ways, the single-step infusion mash conducted in a mash/lauter tun is the best way to brew a barley wine. Because these systems are designed to be used with highly modified pale base malt, there is but one conversion temperature to achieve. That means no decocting, no continual mixing of the mash as you go from one temperature rest to the next, and no pumping of the mash from one vessel to another.

These procedures have their place in the crafting of certain beer styles or when using undermodified malts, but they can be counterproductive when brewing a barley wine. Each of these additional procedures not only reduces the mash to finer particles, but also beats a little bit more of the air out of the mash—air that helps buoy up the mash bed and keeps the mash bed from collapsing on itself and compacting. That little bit of air becomes even more important with larger amounts of malt in your mash tun.

The Monster Mash

If you are like most brewers, you probably brew a barley wine only once or twice a year, so when you do you want it to be special. You want it to last a long time, both in the bottle and in the memories of those who drink it. And you also want it to be a huge beer. A brewer’s first inclination is to fill the mash tun to the very rim with as much grain as it can possibly hold. Resist this impulse. The deeper the mash bed, the slower the runoff, and the greater the chance of compacting or “setting” the mash. Setting the mash will reduce your runoff to a trickle, extend the runoff and sparge into a multiple-hour affair, and increase the likelihood of having to use desperate measures that may lower your gravity. Brewing barley wine will almost certainly tax your brewing system, as well as your patience and concentration, but even the pursuit of excess has its limits.

A traditional English mash tun insulated with wood staves.

Instead of overfilling your mash tun, you may opt for sparging less (adding less water to rinse the grain bed of its sugars). This will give you less wort in the kettle, but the wort you collect will be of a higher gravity (i.e., have more fermentable sugars). Remember the ultimate goal: brewing the biggest beer the best you can. Lowering the yield is almost certainly preferable to overfilling the mash tun and its attendant compromises. It may mean doing multiple brews to fill a fermenter or settling for a lower yield, but the improved quality of the beer and the greater ease of brewing will be a fair trade-off. We therefore recommend that one try not to exceed two to three times normal mash bed depth. Mash consistency should be in the range of medium to medium thick, using slightly less than 1 quart of water (0.9 liters) for each pound of malt.

Even with the most effective mash program, you will not achieve 100% conversion of starch to fermentable sugars. Some percentage (approximately 30 to 35%) can be expected to remain as “unfermentables.” Since there is an increased volume of malt in the mash tun, you will get a fairly large amount of unfermentable sugars in the wort. This is simply a fact. One thing to keep in mind is the optimal temperature/performance ranges for the two enzymes native to malted barley—alpha- and beta-amylase. To help keep unfermentables at a reasonable level, and hence to further the attenuation necessary in avoiding an overly sweet beer, shoot for a mash temperature on the medium-low side between 145 to 152 °F (63 to 67 °C), the span in which the two enzymes, alpha- and beta-amylase, work most effectively together. For the maximum percentage of fermentable sugars, the mash temperature should be maintained at 145 to 146 °F (63 °C) for sixty minutes or more. If the mash temperature is higher than 152 °F (67 °C), the wort will likely be overly sweet and dextrinous, resulting in a poorly attenuated and unbalanced beer. With the amount of malt being used, there will be plenty of unfermentables for sweetness, complexity, mouthfeel, and body. Another added benefit of a more completely converted mash is that it makes for an easier runoff.

Recirculation (Vorlauf)

As with the brewing of other beers, it is advisable to recirculate some of the first wort through the grain bed to remove grain husks and other particulate matter that has inevitably passed through the lauter plates, or screens. The easiest and most consistently effective way to do this is with a pump. If you don’t have a pump, you can gently draw the wort from under the screens and gently pour it back on top of the grain bed. Be careful not to “drill” a hole into the mash bed when returning the wort to the top of the grain. Homebrewers can avoid drilling a hole in the mash by simply placing a plate on top of the surface of the grain in order to catch and diffuse the flow of returning wort.

Many professional breweries are fitted with diffusers or adjustable piping for this purpose, but even then some improvisation may be called for. We have seen this effectively done with a plastic snow shovel used to spread the return flow evenly over the mash bed. Recirculation must be done slowly so as not to collapse (or “set”) the bed or disturb the sediment that has settled to the bottom of the vessel during the ninety-minute mash. Slowly recirculate until the wort begins to run clear or “bright.” But beware: sometimes the wort won’t get completely bright, and the brewer is faced with the temptation of continuing recirculation at the risk of setting and/or cooling the mash bed, thereby compromising ongoing runoff. You may have to settle for only removing the larger particles during the recirculation, and hope that things will clear up as the runoff proceeds. Once the clarity of your wort is satisfactory, begin running off to the kettle.

Runoff and the Sparge

Start the runoff slowly. It is inadvisable to “pull” too hard (runoff to quickly) as this may compact the mash bed. If the runoff is too fast, not only could the mash set, but you run the risk of not thoroughly extracting all sugars from the mash. With the volumes of grain demanded of brewing barley wine, runoff is likely to begin slowly in any case. Don’t force it, be patient. If you are going to sparge start adding the 170 °F (77 °C) sparge water while the wort level is still about an inch above the grain bed. Do not wait until the bed is completely exposed. When the sparge is underway, the hot sparge water will heat the mash bed. Once the hot sparge water has rinsed out some of the sugars and helped to loosen the bed, then slowly speed up the runoff. Remember, it is very important not to start speeding up the runoff too soon. Don’t let the grain bed get exposed but keep the depth of sparge water above the grain to less than two inches. An excess of water will increase the weight pressing on the grain bed, thereby posing the risk of compression, which in turn will reduce the runoff in both volume and efficiency.

If your mash bed does set (and it’s happened to all of us), you can try to underlet. Underletting is the infusion of hot water into the mash tun under the false bottom or lauter plates, thus “lifting” the mash bed off the plates and decompressing the mash bed. This can be a lifesaver, but it can also be a compromising procedure, particularly for the brewing of big beers. Try to avoid long or repeated underletting, since, if done to excess, it can greatly reduce the gravity of your wort.

We have found it extremely useful to measure the gravity of the runnings (wort) when entering the kettle. This allows for tracking its progress and minimizing unpleasant surprises later on. By taking gravities periodically throughout the runoff, you get a good idea of the overall gravity in the kettle, and of how much sugar is likely to remain in the grain bed. A gravity reading is also a good indicator of when and how much to sparge and when to stop the runoff. When making a barley wine, our runnings typically start at 17 to 20 °Plato (1.068 to 1.080) and gradually go up into the mid- to low-20s (1.084 to 1.092). They then start to fall off towards 15 °Plato (1.060) or so. At that point, briefly sparge the grain bed. We usually stop the runoff when the runnings are between 12 °Plato (1.048) and 9 °Plato (1.036), depending on the kettle volume.

At the end of barley wine or other big beer runoffs, brewers with holding tanks or additional kettles will often continue to sparge and collect the lower-gravity runnings. They will use these last runnings to make a “small beer.” The making of a second, or small, beer is a tradition that dates back to the earliest days of brewing and is a good, and enjoyable, way to utilize the fermentables that would otherwise go down the drain.

The Boil

The boiling of the wort, always an important aspect of brew house operation, becomes especially so in the brewing of barley wine. It is often not given due consideration by some home- and microbrewers (as well as by equipment manufacturers). Once the clear wort has been separated from the grain husks and residue through lautering (straining), it needs to be boiled. The wort now contains carbohydrates (fermentable sugars, unfermentable sugars, and starch), as well as protein, amino acids, and other yeast nutrients. Boiling the wort brings about several necessary and beneficial changes: sterilization; halting of enzymatic action; protein denaturing and coagulation; hop bitterness extraction and isomerization; color development; sugar caramelization; evaporation and wort concentration; and the driving off of some undesirable elements (like dimethyl sulfide).

Both the quantity (length) and the quality (vigor) of the boil are important. Without a strong rolling boil, many of the above reactions will not fully take place. Good brewing equipment is designed to facilitate the “turning” or rolling of the boil. Kettle design often incorporates a mechanism that facilitates wort rotation or agitation. Some of the more common devices are internal or external colandria, agitators, swept bottoms, or a kicker panel that delivers more heat to one side of the kettle than the other, thus causing the wort to turn or roll over. These mechanical advantages can also help reduce fobbing during the boil. A brewer should hope to achieve at least twelve complete turns or kettle rotations of the wort in an hour.

Stabilization

Stabilization of the beer is brought about by boiling in three ways: sterilization, the cessation of enzymatic activity through heat denaturing, and protein coagulation. During the boil, wort proteins react with other proteins, as well as with phenolic substances derived from malt and hops, to form large aggregate complexes that will precipitate out of solution. This precipitate is known as “hot break.” The process of protein coagulation is not solely heat-dependent. It is favorably enhanced by the physical action of steam bubbles passing up through the wort. The albumin fractions of wort protein accumulate on the surface of the boil around the steam and air bubbles, causing higher localized concentrations that will more readily flocculate (aggregate) and precipitate. Because of this, and other reasons that relate to hop utilization, the boiling action in the kettle needs to be vigorous. Without a vigorous rolling boil, you will not properly coagulate and precipitate the proteins in the wort.

Physical stability is important for every style of beer but especially so for barley wines because they face such extended storage times. Insufficient protein coagulation and removal can cause problems in the fermenting and conditioning processes, as well as in the finished beer. These problems include incomplete fermentation, tannic/astringent or harsh bitterness, permanent chill or protein haze, and oxidation reactions such as beer staling and poor filtration. A proper and vigorous boil helps reduce all these problems.

Too long a boil, however, can have its own negative effects. It can cause the aggregated precipitates of protein to disassociate. For this reason, it is recommended that the boil be kept to less than three hours and that boiling with hops not exceed ninety minutes.

Some breweries are equipped with stack condensers to be used in a “closed” boiling system. They are designed to precipitate out steam and protein solids and remove them from the boiling wort. In a closed system, this is accomplished as the barm or head pushes up into the condenser unit and is then removed by condensation. Any brewer who has skimmed the initial protein break from a kettle as it reaches a boil understands that these solids that are discarded are something best left out of the wort, and therefore out of the finished beer. Stack condensers can help facilitate this protein removal in much the same way. But these stack condensers, if not properly designed, can also be a deterrent to achieving an adequate boil. If designing a brew kettle, be sure that the heating surfaces of the kettle are properly sized and will not impede boiling or achieving the proper amount of wort evaporation.

Hop Bitterness: Extraction and Isomerization

Hops give bitterness and flavor to the wort. The bitterness comes from iso-alpha-acids, which are derived in the course of the boil from the alpha acids of the hops. Alpha acids are not very water soluble and must be boiled in order to isomerize them or make them water (wort) soluble. But the isomerization process is not solely heat dependent; it is enhanced by physical action as well. The maximum conversion of alpha acids to iso-alpha-acids is about 32 to 35%, and is best achieved with an approximately ninety-minute boil. Most homebrewers, incidentally, can expect 20 to 30% hop utilization. Boiling with hops for more than ninety minutes can extract harsh and unpleasant bitterness. Extended boiling can result in iso-alpha-acids being hydrolyzed to a nonbitter compound called humulinic, thereby lessening their effectiveness. When using longer boil times often associated with the brewing of barley wines, be prepared to hold off on adding your hops until later in the boil.

Another consideration when making high-gravity beers is that, as the gravity of the wort being produced increases, the hop utilization will decrease. We therefore suggest adding 1 to 4% more boiling hops into the kettle when brewing a barley wine. For example, use an additional 1% for a wort of 1.080 SG (20 °Plato) and 4% more for those massive gravities over 1.100 SG (25 °Plato).

Kettle pH

The kettle wort pH should be between 5.2 to 5.4 because this will favor protein coagulation and keep color formation at a low level. The optimum pH for protein coagulation is 5.2. Also a pH of 5.2 or above favors hop utilization and reduces harsh hop bitterness. If your kettle pH is too high, try adding gypsum to acidify it.

Color Formation

Boiling the wort produces an increase in color. The longer the boil, the more caramelization of sugars and the greater the formation of melanoidins, resulting in more color in the finished beer. Extended boils magnify the color representation of pale and specialty malts in particular, demanding the brewer use an even hand in their selection and proportion. Percentages of darker malts must be cut back compared to smaller beers with shorter boil times, in order that their presence enhance, not overwhelm, the color (and flavor) of the finished barley wine. This is of particular concern when trying to produce a lighter-colored or pale barley wine.

Evaporation

One way to enhance the original gravity of your beer is through evaporation. The longer the wort is boiled, the more water will evaporate out in the form of steam, and the more concentrated your wort will become. This will result in a higher gravity, and in barley wine brewing, this a good thing. We recommend boiling a barley wine for 2 to 2 1/2 hours. With a good rolling boil, yielding an evaporation rate of 8 to 12% per hour, gravity can be increased from the end of runoff by 2.5 to 5 °Plato (i.e., from 17 up to 21 or 22 °Plato). The rate of evaporation can be further increased by agitating the wort during the boil. Agitated (or swept) kettles are used in systems that have low heat exchange surface to liquid volume ratios. The concept of a swept kettle is to achieve continuous wort flow over the heat exchange surface, thus bringing a greater amount of liquid in contact with the heating surface.

The question becomes, how do you know if you are getting a boil that is sufficient to achieve the desired amount of wort concentration, properly stabilize your beer, and efficiently extract bitterness from your hops? The easiest way to measure the efficiency of your boil is by measuring the evaporation rate. This is easily done by taking a volume measurement in the kettle just prior to boiling and then again at the end of the boil. The difference is the number of barrels (or gallons) that went up your kettle stack (or into your kitchen) as evaporation. Take that number, divide it by the barrels (or gallons) you started with, and you end up with a percentage representing total evaporation. Divide total evaporation by the number of hours boiled and that is the rate of evaporation per hour. Eight to 12% evaporation per hour is desirable. If you are able to achieve 10 or 11%, you are doing better than many commercial microbreweries.

For example, if you start with 37 barrels (prior to boiling) and have 32 barrels at the end of the boil, then the difference is 5 barrels. Divide 5 barrels by the number of barrels before the boil (37) to arrive at .135, or 13.5% total evaporation. Then divide 13.5% by the length of the boil (1.5 hours, which gives you 9, or 9% evaporation per hour.

Finishing Hops

Unlike the systems devised for the measurement of boiling hops (international bittering units [IBUs] or alpha acid units [AAUs]), there is no good quantitative system to help in the selection of hops to be used for late additions or as finishing hops. Conventional brewing wisdom dictates certain varieties as being particularly suitable for additions of flavor and aroma. Whether the varieties used are traditional or newfangled, finishing hops should always be chosen subjectively for their flavor and aroma. One of the best ways to tell if a particular variety of hops will work for you is to take a couple of hop cones or pellets, rub them between your palms, and then take a good whiff. This will give you an idea of what the hop aroma will be like in your final product, and whether you like it.

Finishing hops can be added to the kettle either at or toward the end of the boil or they can be added to the whirlpool or the hop back. The whirlpool (or swirl tank) is a cylindrical vessel large enough to hold the entire post-boil wort. The hopped wort is run or pumped tangentially into the tank, causing it to swirl around. The rotational momentum causes the solid matter (hops and trub) to gather in a cone-shaped pile on the bottom of the tank. The clear wort is then drawn off from the side.

The hop back is a smaller vessel (usually 5 to 20% the size of the kettle volume) fitted with a screen in the bottom that acts as a strainer. The strainer catches the hop flowers as the wort is drained from the kettle. The brewer can also put dry flower hops into the hop back to extract and capture the maximum amount of the hops’ volatile aromatic component. This is not the same as “dry hopping,” which involves hop additions in the fermenter, conditioning vessel, or cask. In recent years the hop back has lost practical favor to whirlpools in breweries where pellet hops are more frequently used. Some brewers, however, believe that nothing is as effective in adding fragile hop aromas as the hop back.

Pitching the Yeast

It is a good idea to have your yeast prepared and ready to pitch (add to the cooled wort) before the end of the boil. A good healthy ale yeast culture will be needed, preferably one from a recent fermentation because that yeast will be freshest and strongest. We do not recommend brewing a barley wine with a yeast culture’s first generation, but if you must use a new culture, make sure you grow a good strong starter so that there will be enough yeast to achieve the proper pitching rate. It is extremely important to pitch enough yeast in any brew, and this is especially true with barley wines. The proper pitching rate for any beer is one million cells per milliliter per degree Plato. So, for a 23 °Plato barley wine (1.092), you will need 23 million healthy yeast cells per milliliter in your pitched wort. That’s a lot of yeast.

It is also important to ensure that the yeast you are using is alive and healthy. This can be done quickly and easily by a methylene blue staining test. Without pitching a sufficient quantity of healthy yeast, you will not get proper attenuation, and the resulting beer will be too sweet.

Every professional brewer or serious homebrewer should have access to a microscope and hemocytometer (used for counting yeast cells in a sample). These instruments will allow you to check the pitching rate and the viability of the yeast. If you don’t have access to a microscope and a hemocytometer, we advise 1 1/2 to 2 times the regular pitching volume or weight that would normally be used for a beer of 13 °Plato (1.052) original gravity. Again, your best bet is to use yeast from a recent fermentation that went well or a properly grown-up (two- or three-step) starter from a packet of liquid yeast. When making high-gravity beers, it is always better to overpitch than to underpitch. One must significantly overpitch to see obvious negative effects.

There are also times when more yeast must be pitched, like when a disappointing hemocytometer reading is taken or when fermentation simply slows down. It is therefore advisable to have more healthy yeast on hand than went into the original brew. Keep this surplus yeast chilled and ready to go in the event of a sluggish fermentation. In professional breweries this is not ordinarily a problem, but in most cases homebrewers pitch all the yeast their starter has yielded. A second, or backup, starter may seem overly fussy, but it can be just the thing to jump-start a slow fermentation.

Knock Out (Casting Back) and Cooling the Wort

The wort is cooled as with other beers, but because of the greater amount of malt and hops used, it is highly likely that there will be more cold break (trub) to settle out. This can be removed in the whirlpool or by letting the hot wort stand in the kettle for fifteen to thirty minutes before knocking out (casting back) into a fermenter. An option for ensuring greater trub removal is to knock out into a clean fermenter and let the wort sit for an hour or two before drawing the trub off the bottom (if you have cylindroconical fermenters) or transferring the beer to another fermenter, leaving the trub behind. Naturally there are risks involved in transferring unfermented beer between vessels—sanitation must be above reproach. Increasing the number of surfaces that come in contact with the wort always increases the risk of infection.

It is important to make sure you get the proper amount of oxygen (or air) into the wort as you send the wort to the fermenter or cast back (see chapter 3). Without enough oxygen, the beer will not fully attenuate, and may not sufficiently begin fermenting. If you have a good temperature control on your fermenter, cast back at or just above your maximum desired fermentation temperature. The initial higher temperature may help get the fermentation started. We suggest that the fermentation should run between 66 to 72 °F (19 to 22 °C). If you do not have an accurate temperature control on your fermenter (as with many homebrew systems), we suggest you send the wort back 2 to 6 °F (-17 to -14 °C)—depending on the ambient temperature—below the maximum desired fermentation temperature. You will then have to watch the fermentation temperature carefully.

Fermentation

Fermentation is an exothermic reaction and temperatures can climb quickly. High-gravity beers can work themselves into an overheated frenzy if left to their own devices. You don’t want your fermentation to run too warm. High-gravity fermentations will naturally produce a greater amount of esters. Higher-temperature fermentations will exaggerate this phenomenon, producing both more esters and higher alcohol. Combining the two (high-gravity and high-temperature fermentations) can create some pretty strange-tasting beers.

Copper square fermenters.

We recommend that fermentation temperature be kept between 66 and 72 °F (19 and 22 °C). This of course is dependent on the yeast strain used—some ale yeast strains will work perfectly fine at temperatures as low as 60 °F (16 °C). But you do want to have some of those ale yeast esters and characters in your beer so don’t ferment at too low a temperature even if your yeast is capable of doing so. It is also doubtful that at lower temperatures your fermentation would be completed. It is important to keep the fermenting beer in a temperature range that is not so high that it will produce excessive esters and not so low that the yeast quits fermenting.

As fermentation progresses, you may need to rouse (or stir up) the yeast to help keep the fermentation going. Studies have shown that periodically agitating the beer to keep the yeast in suspension speeds up fermentation and achieves greater attenuation. Rousing or agitation can be done in a variety of clean and careful ways if you have an open fermenter, but the easiest way is to blow carbon dioxide (CO₂) in through the bottom valve. It is also possible to rouse by using a sterilized pump. By pumping the yeast and wort from the bottom of the tank onto the top, you can get the yeast back into suspension. This should be done at low speed and with a minimum of splashing. For smaller homebrew batches, the yeast can be roused manually by agitating the fermenting vessel. With some highly flocculant strains, keeping the yeast in suspension will be the key to achieving desired terminal gravity.

Once the initial, or active, fermentation is finished, let the beer rest “warm,” at or around fermentation temperature, for another seven to ten days. This will allow the yeast to completely attenuate the beer as well as to reduce diacetyl and other metabolic by-products of fermentation. It is worth noting that British malt is higher in the amino nutrients that can result in higher diacetyl levels, so this “warm” rest becomes even more important when using British malt. After the diacetyl rest is complete, chill the beer for aging.

Cold Aging

When the warm rest is complete, chill the beer to 32 to 52 °F (0 to 11 °C) for cold aging. This stage should last from one to three months, depending on the time and equipment you are able to devote to it. Most brewers agree that for barley wines to achieve maximum flavor development, aging with the yeast still in the fermenter is fairly important. You do not, for example, want to cold-crash your beer and then immediately filter it. The question then becomes, for how long and on how much yeast? We feel that after chilling the beer, it is best to let it go for a week or so before trying to remove any of the yeast. After that time you will want to chill the tank to below 40 °F (4 °C) and remove as much of the precipitated yeast as possible. The colder aging temperature helps minimize yeast autolysis and its negative effects.

You want to remove the yeast because starting around this time the yeast begins the process of self-digestion or autolysis. When this occurs the yeast releases enzymes that cause the decomposition and solubilization of macromolecules, organelles, and the cell wall. This allows the now soluble cell components to leak into the surrounding environment (your beer), resulting in a negative flavor impact. This “yeast bite” is often described as tasting yeasty or meaty. In a cylindroconical fermentation (uni) tank, you can draw yeast off from the bottom of the vessel. With other systems you will have to transfer the beer to a clean vessel, leaving the yeast sediment behind on the bottom. After the majority of the yeast has been removed, the aging process can continue for up to a year before packaging.

Filtration

Once fermentation has ended, the beer has been chilled, and the yeast sediment removed, it is time to decide if you want to filter the beer before it enters the long, slow, aging phase of its conditioning. Filtration removes haze-forming proteins, as well as yeast left in suspension, thus resulting in a bright and stable beer with cleaner and more defined flavor. But long periods of cold aging can bring these changes too. One problem with filtration is that it also removes other things from the beer—like color, flavor, body, hop bitterness, and hop aroma.

Is it necessary to filter a well-aged beer? We don’t think so. We believe the proper amount of cold storage can leave a beer in better shape than filtration. But the problem is that the proper amount of aging varies greatly from beer to beer.

Aging times may exceed a year for some beers, and for commercial breweries it can be very costly to age a beer that long, to say nothing of the clutter that occurs when barley wine brewing time rolls around and you’ve still got the previous year’s offering taking up tank space. It is also very difficult to keep your hands off a beer for that long, and the temptation is such that the whole batch could be “tasted off” before its scheduled release. But one must remember to be patient.

An alternative worth mentioning is pad filtration. A pad filter uses cellulose pads usually impregnated with diatomaceous earth (DE). These pads are produced in various grades (or porosity size). By using a pad that is fairly open, or of a high porosity, a brewer can remove some of the yeast and larger haze-forming protein complexes without stripping out too much of the desirable constituents that you want to remain in the beer. The filter pad that we have used with good results is the Schenk HS 6000 (formerly the AF 6000).

Packaging: Kegs vs. Bottles

There are several options for packaging a barley wine. The larger the package, the proportionately smaller the head space, and hence the lower oxygen-to-beer ratio. Oxygen is the foe of all packaged beers. Oxygen in a packaged beer can quickly degrade the flavors and stale the beer. This makes kegs a superior package for beer storage. But kegs are not always the most convenient packages to move, use, and store and it is nice to have smaller containers from which to sample. Always bottle at least some of your barley wine. This will allow you to take small taste samples and track its progress as it ages without having to compromise a larger quantity by tapping a whole keg. In addition, bottles of barley wine make great gifts for fellow brewers and beer writers who may be visiting your brewery.

Bottle Conditioning

Bottle conditioning is a more traditional way of packaging your beer and it is the easiest way to give some sparkle to your bottled beer at home. If done right, bottle conditioning will give a softer and more mellow carbonation than keg storage under pressure. Another benefit of bottle conditioning is that the yeast invariably present in the beer will scavenge whatever oxygen is present in the head space and metabolize it, keeping it from reacting with other components and causing staling.

There are certain difficulties associated with bottle conditioning high-gravity beers. Unlike other ales, barley wines have a very high alcohol content and are subject to long maturation periods prior to bottling. For these reasons, one cannot depend on the few worn-out yeast cells that might be in suspension to carbonate the beer. What this means is that you must dose with a measured amount of fresh and active yeast along with the primings. We have found that the best and easiest way to do this is to prime with actively fermenting wort, either from another fermenter that is at the proper stage of fermentation or with a yeast starter made specifically for this purpose. Our best results are achieved when we dose the entire amount to be bottled with fermenting wort and allow it a short time to mix before bottling. The actively fermenting wort should be at 10 °Plato (1.040) and have approximately 25 million yeast cells per milliliter in suspension. We recommend dosing with 4 to 6 liters fermenting wort per U.S. barrel of beer to be primed.

Once the primed beer has been bottled it will need to be stored at a relatively warm temperature (65 to 70 °F, 18 to 21 °C) for thirty or more days. Once it has warm conditioned enough for carbonation to build up, it should be stored again at a cooler temperature. Cellar temperatures—48 to 55 °F (9 to 13 °C)—are best. We recommend waiting at least 120 days after priming before partaking in this biggest of brews, your barley wine.

Laying Down the Beer (Cellaring)

Once the beer has been packaged it is time to put it away and give it any additional aging that the brewer feels it might need. Even though the beer may be drinkable (really quite drinkable) at this stage, there are some definite benefits gained by letting the beer continue to mature. The beer changes over time. How and how much it changes depends on a number of variables—gravity, hopping rate, hop variety, alcohol content, level of microbiological contamination, malt bill, oxygen present, cellaring temperature, and so forth. The beer should now be aged at cellar temperatures (48 to 56 °F, 9 to 13 °C) or below.

A growing body of evidence suggests that aging beer, like wine, is best done at cellar temperatures. Several brewers gave us information suggesting a barley wine aged at cellar temperatures will often have less of a sharp edge, a rounder, fuller character, and a more melded and cohesive flavor profile.

We have been able to put this hypothesis to the test over the last year and a half it took us to research and write this book. We found that many beers cellared over this period of time did indeed taste better than their counterparts that were held in cooler temperatures. Their flavors were more robust and round. We also found that some were not as clear or bright as those aged at lower temperatures and that this had a flavor impact as well. Additionally, we found that barley wine aged at temperatures above 60 °F (16 °C) did not fare as well as those aged at cellar temperatures, or below 48 °F (9 °C). We attributed this to the fact that chemical reactions are accelerated at higher temperatures. This may mean that beers cellared between 48 and 56 °F (9 and 13 °C) may not fare as well as those held at lower temperatures over the long haul. Our research (we are happy to say) is continuing in this area.

Our recommendation is to decrease the temperature of cellaring as the length of aging increases. For example if you are holding a case of Bigfoot, keep it at 50 °F (10 °C) for the first year or two. Then, if you are patient enough to have any left, move it to a cooler for the rest of its life. The higher gravity, less hoppy barley wine will do better with extended cellar temperature aging.