Be Bold, Get Cold!
I like to talk about beer. I like to walk into my local tavern and ask my fellow patrons, “So, what’s the difference between lager and ale?” Answers range from “there’s no difference,” to “lagers are light-colored beers and ales are dark,” to “huh?”
I then joyfully launch into my pedantic explanation: “Ales are beers that are fermented with top-fermenting yeast at relatively warm temperatures, while lagers are cold-fermenting beers with yeast that sediment thickly near the bottom. Lagers, unlike traditional ales, also undergo a longer period of cold conditioning from which they take their name. In German, ‘lager’ literally means ‘to store.’”
Oftentimes, my fellow imbibers’ eyes glaze over as they search the bar for a seat farther from my proximity. And other times, people argue with me (I’ve had people insist that Budweiser is absolutely, positively not a lager). And occasionally — rarely — the listener tunes in for more. I’m always happy to oblige.
By 1200 A.D., German brewers had discovered that cooler fermenting and storage temperatures produced cleaner beers with subtler flavors. This probably had to do with the fact that cooler temperatures inhibited the formation of esters. So in the cool, dark, limestone caves of southern Germany, a form of natural selection began to take place. What endured in the bottom of German fermenting barrels was yeast that preferred cooler temperatures, while their cousins, who preferred warmer temperatures, slowly vanished.
None of this was truly understood until 1841, when yeast was finally discovered to be the catalyst of fermentation. Soon after, scientists were able to separate and propagate single yeast cells. Pure cultures were born and lager yeast was soon to become the most widely used yeast on the planet.
Two technological achievements were soon to happen. In 1842, brewers in the town of Plzeñ, in what is now the Czech Republic, introduced the blonde pilsner. In a world of red, brown and black beers, pilsner must have been something of a novelty. One of the first truly clear, golden beers, pilsner quickly gained popularity in Germany. By the next century, nearly every other brewer in the world would try to emulate it.
The other great technological achievement came in 1860, when commercial refrigeration became available. Brewers anywhere could finally control the temperature of their fermenting beer with regularity.
In time, “lager brewing” became the synonym for “pilsner beer” over much of the world — even though the Germans had been brewing dark, malty lagers for centuries. Which brings us back to that common misconception that I mentioned earlier.
Why Brew Lager?
But we are brewers, not unenlightened bar patrons, and all that history sounds familiar. So why do most homebrewers brew ales and turn their backs on lagers? Because brewing ale is relatively easy. Ales are wonderful, easy to make and distinctive. They are tough, heady brews that are full of flavor.
But nothing can showcase a brewer’s skill like a lager. Lagers are delicate creations that must be tended and nurtured by the brewer. Time and craftsmanship are essential to the brewing of lagers. The fragile, clean flavor of lager leaves little room for error and truly canvasses the brewer’s skill.
Equipment (or the lack thereof) discourages some homebrewers from making lager: Every homebrewer in America likely owns a refrigerator, but probably few of them own two. And even fewer own a spare deep chest freezer.
Time is also a major factor in a homebrewer’s preference for ales. While an ale might be ready to drink in two to three weeks, some styles of lager may take more than three months! Simply stated, lagers are brews created out of time, care and patience. Which is why every brewer should brew one.
Lager Yeast
Colder fermentation temperatures lend a cleaner flavor to beer because the yeast release significantly less compounds that affect flavor, such as fruity esters and fusel oils. Ale yeast tend to leave a more complex, spicy and fruity character, while lager yeast showcase the harmony of malt and hops.
It is important to choose the right strain of yeast when brewing lager beers. In addition, remember that liquid yeast, fresh sediment (from a starter) or pure cultures work best when fermenting lagers.
For pilsner and lighter-colored lagers, find yeast with medium-high to high flocculation to assure that the yeast drops out and clears the beer. Use yeasts such as Wyeast 2035 (American Lager), Wyeast 2278 (Czech Pils) and White Labs WLP800 (Pilsner Lager).
For darker lagers, flocculation is not as much of an issue. For märzens, bocks and dopplebocks try to find yeast cultures that produce beers that are rich, full-bodied and malty, such as Wyeast 2206 (Bavarian Lager), Wyeast 2308 (Munich Lager) and White Labs WLP920 (Old Bavarian Lager).
As in ale brewing, starter cultures are a good way to guarantee a strong fermentation. This extra step becomes almost essential in fermenting lagers. Because of the lower temperatures, lager yeast are not as active as ale yeast, and lager cultures do not multiply as much. Therefore, the viable yeast cell count at pitching should be maximized. Generally, a culture should be made from a smack pack or pure yeast vial and built from a twelve-ounce starter into a one-gallon starter in two or three steps. The beer should be allowed to finish fermenting in the starter vessel and then poured off the sedimented yeast right before pitching.
An even better idea is to discard this finished beer and add a pint or two of sterile wort to the starter vessel a few hours before pitching. With this method, the yeast will be fully active when it enters its new environment. The yeast should be pitched at the same temperature as the ready wort so as not to shock the cells and prolong the lag before primary fermentation begins.
An optional practice that some brewers have adopted is to warm the secondary before dropping the beer slowly to lagering temperatures. This may help to improve attenuation by energizing the yeast before they drop into their cold slumber (this practice is also
commonly used to speed up diacetyl reduction). If you’d like to follow this practice, warm the beer to 60° or 65° F and hold at that temperature for 24 hours after the beer has been racked to the secondary.
Lager Hops
American craft brewers often brew ales and the ales they brew are often heavy in finishing hops — heavier even than their related brews across the pond. These beers have hops in the nose and hops in the finish. Oftentimes, the only impression these beers leave are grassy hop bitterness. On the other hand, many American lagers are pale, fizzy brews with only trace amounts of detectable hops.
Good lagers enjoy hops mingled and laced through the body of malt. This is a fine balancing act achieved by adding the hops circumspectly and moderately through the boil. Generally, flavoring hops are added in half and quarter ounces after the initial bittering hops have been added. Almost no German lagers use dry hopping (though I have heard of one) to finish their beers. Even the most ardent hopheads should use moderation when adding hops to most styles of lagers.
In ale brewing, hops high in alpha acid are often used in the beginning of the boil to add specific bitterness. Mainly, this is because the brewer uses less hops to achieve the same amount of bitterness. However, many German brewers use only noble hops, such as Hallertau and Saaz, to bitter their beers. While bittering (high alpha acid) hops may be used in lager brewing, it should be remembered that lager beer is generally less
bitter than ale.
Primary Fermentation
To brew lagers it is absolutely necessary to control fermentation temperature. The beer should be fermented between 45° and 55° F for one to two weeks and the brewer must keep this temperature consistent. There are a couple of methods for achieving this, but the easiest way is to procure a deep chest freezer or spare refrigerator with a separate adjustable thermostat. (For information on building your own temperature-controlled lager fridge, see “Ice Cold Beer” in the November issue of BYO.)
Deep chest freezers are the brewer’s first choice for convenience and control when it comes to fermentation and lagering. With a separate thermostat made especially for lagering (available from many homebrew-equipment suppliers) the brewer can control the temperature at which their beer will ferment — and do so with precision. Deep chest freezers, in combination with a thermostat, can also reach the low temperatures needed for perfectly lagering beer.
A spare refrigerator works well for this purpose, but it probably won’t be able to reach close-to-freezing temperatures. Some older refrigerators have a wide-range manual thermostat. Test your refrigerator to see what its temperature range is. If you can reach temperatures as high as 45° or even 50° F and temperatures as low as 40° or even 35° F, you have the ability to lager your beer.
Look to spend at least $150 for a brand-new, small cubic-capacity deep chest freezer and $300 for a freezer able to hold two or more carboys. Usually the classified ads will yield a less-expensive option, but be warned that older refrigerators can be energy hogs.
Refrigerators and freezers, even purchased used, can be expensive. They take up space and consume energy. This might deter some homebrewers from trying to brew a lager. Thankfully, there are a few alternatives.
The best option is to use the ice-bath method. This method may take some practice but once mastered it offers an alternative to the spare refrigerator or freezer.
Basically, the carboy is immersed in a large trash can filled partway with water. Ice is added to the trash can until a floating thermometer (which you can buy at any pet-store fish department) indicates the desired temperature. The ice water should cover — or come close to covering — the beer without (obviously) splashing over the top of the fermenter.
You’ll have to add ice to the trash can to regulate the temperature. It may be desirable to install a spigot near the bottom of the can to drain water. You also could use a siphon, or drill a hole in the garbage can about three-fourths of the way up; when the water level gets that high, it’ll simply flow out the hole.
If wrapped with an adequate piece of house insulation this trash-can method works well, though the beer must be checked frequently (at least two or three times daily) to monitor the temperature. Keep the ice bath someplace in the house or garage where the ambient temperature stays relatively stable.
Whatever fermentation method you choose, it is important that the temperature remains consistent. Constant temperature fluctuation of more than 2 or 3 degrees over twelve hours can cause the yeast to flocculate early and stop working. If the beer warms too much it will develop ale-like characteristics.
The Secondary
Two things should happen before secondary fermentation begins: The krausen should fall back into the beer and the color of the beer should darken. Yeast and sugar will still be present in moderate amounts and the beer should still be fermenting, albeit slowly.
Initial fermentation takes one to two weeks; afterward, the beer should be racked to a secondary vessel or keg. The temperature should then be slowly lowered to as cold as possible over seven to ten days. Do not exceed a temperature drop of more than four degrees over a period of 24 hours. The temperature should be lowered slowly to insure that the yeast will continue their consumption of sugars.
Lagering
As the beer sits at its cold temperature it conditions into perfection. Acetaldehyde and diacetyl are reduced and the remaining yeast and other particulates slowly settle out of the beer.
Lager the beer as cold as possible without freezing for 60 to 90 days (in some cases longer) depending on the style of the beer and your own preference. If you’re using the immersion method this will mean keeping the trash can loaded with plenty of ice. It must be carefully insulated and regularly monitored.
Light lagers should be crystal clear before they are removed from lagering temperatures. Many styles may be ready in as little as six weeks. Other malty, rich lagers, such as the Oktoberfest-Märzen style, may be allowed to lager for as long as six months to completely blend and mellow their complex flavors. With longer lagering times, freezers and refrigerators become must-have items.
Don’t get excited. Relax and wait for the beer to finish. Monitor airlock levels and keep the beer quiet and away from light.
When the beer has fermented to its target final gravity, prime with corn sugar (or whatever priming sugar you prefer) and bottle, or force-carbonate your lager in a keg, just as you would with an ale.
Extract Tips
There are many excellent extract bases for lager brewing. Look for German-made extracts such as Ireks and Bierkeller. When brewing pilsners and other light lagers, try to find the palest malt extracts available.
Generally, extract worts do not require boil times as long as all-grain worts. Long boils darken the wort, especially extract worts. If the brew is a dunkel or bock this does not present a problem. But for lighter beers, try to keep boil times down around 45 minutes. (Just a caution: This may sacrifice some hop utilization.)
All-Grain Tips
Traditionally, German and Czech lagers are brewed using under-modified malts that require difficult decoction mashes and protein rests. Brewers who are attempting to brew their first lager should stay away from complex decoction mashes at first and instead concentrate on finding a good, well modified two-row malt.
For brewing pilsners and helles lagers only the lightest malt (1.5° to 2° Lovibond) should be used. Also, for lighter-colored beers, a protein rest is recommended. This helps enzymes to break down proteins in the malt, improving the head, body and clarity of the beer.
To initiate the protein rest, stabilize the mash temperature at 122° F and rest it for 30 minutes. Afterward, use bottom heat or infusions of boiling water to raise temperature to saccharification rest. Pilsner saccharification rests should be targeted at around 149° to 151° F. This range will convert the majority of starches into sugar and will build a wort of lighter character and mouthfeel with fewer dextrins. Anticipate the conversion to take up to 50 percent longer at this temperature and be sure to check dextrins percentage with an iodine test. Maltier, sweeter lagers may be targeted at warmer temperatures, between 154° and 158° F.
Lager Recipes
Because lager brewing is more complex than ale brewing, it is a good idea to start lager brewing with a dark, malty brew that will give enough flavor to hide any minor mistakes and still be tasty. After the steps become familiar, the brewer will have a better chance at perfecting the extremely delicate pilsner recipe included below. All of these recipes yield a five-gallon batch of beer.
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Munich Dunkel
5 Gal; OG = 1.054; FG = 1.013 to 1.015; IBU = 23, partial grain
In Munich they brew dunkel, which simply means “dark” in German. The recipe below is for a dark, clean, malty lager that goes great with oompah bands and Bavarian pretzels.
Ingredients:
- 6.6 lbs. Bierkeller pale malt extract (unhopped) or 5 lbs., 10 oz. light dry malt extract (DME)
- 1 lb. medium German crystal malt (40° Lovibond)
- 8 oz. cara-Vienne (20° Lovibond)
- 4 oz. chocolate malt
- 5.1 AAU Hallertau Mittelfruh hops (1 oz. at 5.1% alpha acid) at boil
- 2.55 AAU Hallertau Mittelfruh hop pellets or whole hops (0.5 oz. at 5.1% alpha acid) at 20 minutes
- 1.05 AAU Saaz pellets or whole hops (0.25 oz. at 4.2% alpha acid) at 50 minutes
- Starter of Wyeast 2206 (Bavarian Lager), Wyeast 2308 (Munich Lager) or White Labs WLP920 (Old Bavarian Lager)
Step by Step:
Add crushed grains to 1/2 gallon 155° F water. Hold for 20 minutes. Run entire volume through kitchen colander (preferably fine wire mesh) and rinse with 3/4 gallon of 170° F water. Add malt extract. Top off boiling vessel to 5.5 gallons. Boil for 60 minutes, adding hops as indicated by the hopping schedule above.
Cool wort as quickly as possible to 55° F and pitch yeast starter. Hold temperature for 14 days. Transfer lager to secondary fermenter or keg. Slowly lower temperature to as cold as possible without freezing. Hold this temperature for 60 days.
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Munich Dunkel
5 Gal; OG = 1.054; FG = 1.013 to 1.015; IBU = 23, all grain
Ingredients:
- 8 lbs. two-row pale lager malt (1.8° Lovibond)
- 1 lb. medium German crystal malt (40° Lovibond)
- 8 oz. cara-Vienne (20° Lovibond)
- 4 oz. chocolate malt
- 5.1 AAU Hallertau Mittelfruh hops (1 oz. at 5.1% alpha acid) at boil
- 2.55 AAU Hallertau Mittelfruh hop pellets or whole hops (0.5 oz. at 5.1% alpha acid) at 20 minutes
- 1.05 AAU Saaz pellets or whole hops (0.25 oz. at 4.2% alpha acid) at 50 minutes
- Starter of Wyeast 2206 (Bavarian Lager), Wyeast 2308 (Munich Lager) or White Labs WLP 920 (Old Bavarian Lager)
Step by Step:
Add 2.5 gallons 130° F water to crushed grains. Stabilize at 122° and rest for 30 minutes. Then add 1.25 gallons boiling water and bring mash to 155° to 157° F (adding bottom heat if necessary). Rest, checking for conversion at 45 minutes. Mash out at 168° F and sparge with 5 gallons water. Collect 5.5 gallons of wort and continue with boil.
Boil per hopping schedule indicated above. Total boil time is 60 minutes. Cool beer as quickly as possible to 55° and pitch yeast starter. Hold temperature for 14 days. Transfer lager to secondary fermenter or keg. Slowly lower temperature to as cold as possible without freezing. Hold this temperature for 60 days.
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Czech-Style Pilsner
5 Gal, O.G = 1.049 F.G. = 1.010 IBU = 35, partial grain
This beer will require full attention and all of the brewer’s resources. The long lagering time will ensure that this beer is clear and golden.
Note: The water in Plzen, the Czech town where this style of beer originated, is very soft. If the water is hard in your area, try boiling your water to settle out the “temporary hardness.” Boil for 30 minutes and let cool till lukewarm. Siphon or gently decant water off white sediment. (Temporary hardness means the water contains soluble calcium and magnesium; if you boil the water, these bicarbonates will precipitate out.)
If the water is permanently hard in your area — which means boiling won’t help — try using distilled water and add a small amount of gypsum (three teaspoons per five gallons) to raise the mineral content of the water. Another option: Brew with a 50-50 blend of tap water and distilled water.
Ingredients:
- 6.5 lbs. Bierkeller pale malt extract or 5.5 lbs. extra light dry malt extract (DME)
- 1 lb. light Munich (9° Lovibond)
- 8 oz. carapils (1.7° Lovibond)
- 5.1 AAU Hallertau hops (1 oz. at 5% alpha acid) at boil
- 2.1 AAU Saaz hop pellets or whole hops (0.5 oz. at 4.2% alpha acid) at 15 minutes
- 2.1 AAU Saaz hop pellets or whole hops (0.5 oz. at 4.2% alpha acid) at 30 minutes
- 1.05 AAU Saaz hop pellets or whole hops (0.25 oz. at 4.2% alpha acid) at finish
- Starter of Wyeast 2278 (Czech Pils)
Step by Step:
Add crushed grains to 1/2 gallon 155° F water. Hold this temperature for 20 minutes. Raise to 165° F. Run entire volume through kitchen colander (preferably fine wire mesh) and gently rinse with 3/4 gallon of 170° F water. Add malt extract. Top off boiling vessel to 5.5 gallons. Boil for 45 minutes, adding hops as indicated by the hopping schedule above. Cool the beer as quickly as possible to 50° F and pitch yeast starter. Hold temperature steady for 14 days. Transfer lager to secondary fermenter or keg.
Slowly lower the temperature to as cold as possible without freezing the beer. Hold this temperature for 90 days.
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Czech-Style Pilsner
5 Gal, O.G = 1.049 F.G. = 1.010 IBU = 35, all grain
Ingredients:
- 8 lbs. two-row pilsner malt
- 1 lb. light Munich (9° Lovibond)
- 8 oz. carapils (1.7° Lovibond)
- 5.1 AAU Hallertau hops (1 oz. at 5.1% alpha acid) at boil
- 2.1 AAU Saaz hop pellets or whole hops (0.5 oz. at 4.2% alpha acid) at 20 minutes
- 2.1 AAU Saaz hop pellets or whole hops (0.5 oz. at 4.2% alpha acid) at 40 minutes
- 1.05 AAU Saaz hop pellets or whole hops (0.25 oz. at 4.2% alpha acid) at finish
- Starter of Wyeast 2278 (Czech Pils)
Step by Step:
Add approximately 2.25 gallons 135° F water to crushed grains. Stabilize at 122° F and rest for 30 minutes. Then add one gallon boiling water and bring mash to around 149° to 152° F. Rest, checking for conversion at one hour. Mash out at 168° F and sparge with 4.5 gallons water. Collect 5.5 gallons of wort and continue to boil. Boil as indicated by hopping schedule above. Total boil time is 60 minutes.
Cool beer as quickly as possible to 45° F and pitch yeast starter. Hold temperature for 14 days. Transfer lager to secondary fermenter or keg. Slowly lower temperature to as cold as possible without freezing. Hold this temperature for 60 days.
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Hearty Bock Bier
5 Gal; O.G = 1.066 F.G. = 1.016 IBU = 25, partial grain
Early bock beers were brewed with plenty of wheat and were dark and malty. Bock is not bitter beer; instead, it should be brewed with the emphasis on the malt. The addition of small amounts of aromatic or biscuit malt will add a pleasant malt aroma to the beer.
Ingredients:
- 4 lbs., 14 oz. Bierkeller pale malt extract or 4 lbs. light dry malt extract (DME)
- 3.25 lbs. dry wheat malt (2° Lovibond)
- 1.5 lbs. German crystal malt (40° Lovibond)
- 0.5 lbs Cara-vienne (20° Lovibond)
- 0.5 lbs biscuit or aromatic malt (22° Lovibond)
- 0.5 lbs chocolate malt
- 6.3 AAU Hallertau hops (1.25 oz. at 5.1% alpha acid) at boil 2.5 AAU Hallertau hops (0.5 oz. at 5.1% alpha acid) at 30 minutes
- 2.5 AAU Hallertau hops (0.5 oz. at 5.1% alpha acid) at 30 minutes
- Starter of Wyeast 2206 (Bavarian Lager) or White Labs WLP920 (Old Bavarian Lager)
Step by Step:
Add 0.75 gallons water to grains and slowly raise temperature to 155° F. Hold for 20 minutes and raise to 165° F. Run entire volume through kitchen colander (preferably fine wire mesh) and gently rinse with one gallon 170° F water. Add malt extract. Top off boiling vessel to 5.5 gallons.
Boil for 1 hour, adding hops as indicated by the hopping schedule above. Cool beer as quickly as possible to 50° F and pitch yeast starter. Hold temperature for 14 days. Transfer lager to secondary fermenter or keg. Slowly lower temperature to as cold as possible without freezing. Hold this temperature for 60 days.
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Hearty Bock Bier
5 Gal; O.G = 1.066 F.G. = 1.016 IBU = 25, all grain
Ingredients:
- 6 lbs. two-row lager malt (1.8° Lovibond)
- 3.5 lbs. wheat malt (2° Lovibond)
- 1.5 lbs. German crystal malt (40° Lovibond)
- 0.5 lbs. Cara-vienne (20° Lovibond)
- 0.5 lbs. biscuit or aromatic malt (22° Lovibond)
- 0.5 lbs. chocolate malt
- 6.3 AAU Hallertau hops (1.25 oz. at 5.1% alpha acid) at boil
- 2.5 AAU Hallertau hops (0.5 oz. at 5.1% alpha acid) at 30 minutes
- 2.5 AAU Hallertau hops (0.5 oz. at 5.1% alpha acid) at 30 minutes
- Starter of Wyeast 2206 (Bavarian Lager) or White Labs WLP920 (Old Bavarian Lager)
Step by Step:
Add approximately 3 gallons 130° F water to crushed grains. Stabilize at 122° F and rest for 30 minutes. Then add 1.5 gallons boiling water and bring mash to around 155° to 157° F (add bottom heat if necessary). Rest, checking for conversion at 45 minutes to an hour. Mash out at 168° F and sparge with five of gallons water. Collect 5.5 gallons of wort and continue to boil.
Boil as indicated by the hopping schedule above. Total boil time is 60 minutes. Cool beer as quickly as possible to 55° F and pitch yeast starter. Hold temperature for 14 days. Transfer lager to secondary fermenter or keg. Slowly lower temperature to as cold as possible without freezing. Hold this temperature for 60 days.
