International Lagers

In 1842, the beer world changed forever. In that year, a little-known brewery in what is now Pilsen (Plzen), Czechoslovakia brewed a clear, golden lager. Subsequently, brews adapted from this original Pilsner beer spread across the globe. The basic, widely-brewed version of this beer style could simply be called International lager. This name emphasizes its ubiquity and the fact that, for many people around the world — especially those in countries without a vibrant beer culture — this style defines the word “beer.”

In the US, beer drinkers know these beers — beers like Heineken, Becks, Grolsch, St. Pauli Girl and the like — in their green-bottled import versions.

You might think that these beers would be the last thing on the minds of homebrewers, who tend to gravitate more to hoppy, big or dark beer styles. However, if you read the online brewing forums, requests for “Heinie” clones pop up at a surprisingly high frequency.

I based the recipes in the article on Heineken, but all of these beers taste very similar. Of all the beers you could brew, an International lager is one that will highlight your skills as a brewer the most. There’s nothing for faults to hide behind in this beer, so you really have to pay attention to how you brew it. Keep in mind that even the big commercial breweries don’t do this flawlessly — they achieve some of their consistency through blending. Here’s how you can brew one at home.


Soft Water

To brew an International lager, you need to use water with a low level of dissolved minerals (i.e. “soft” water). Ideally, the water should contain 50 ppm calcium ions (Ca2+) or less and as close to no carbonate ions (HCO3) as is possible. “Soft” water gives the beer a rounded flavor that de-emphasizes the hop bitterness.

The easiest way to get appropriately “soft” water is to dilute your tap water with either distilled water or water treated by reverse osmosis (RO water). Then, you can add calcium chloride (CaCl2) or calcium sulfate (from gypsum, CaSO4*7H2O) to hit the calcium ion target. If you have a water report from your local utility and access to brewing software, you can figure out the exact plan for your water treatment. If you don’t — but you know that your water is soft, medium or hard — follow one of the simple water treatment plans below.

Water for Extract Brewers

You will need about 6 gallons (23 L) of water total to make your 5 gallons (19 L) of extract beer. As an extract brewer, you will not need to worry about the level of calcium in the water. So, you really have two options:

The best option is to simply brew the beer using distilled water and let the minerals in the malt extract determine the mineral content in your wort.

Your second option is to dilute your local water with distilled water. If you have soft water, dilute it 1:1 with distilled water. If you have “medium” water — not particularly soft or hard — dilute your tap water 3:1 (4.5 gallons (17 L) of distilled water and 1.5 gallons (5.7 L) of medium tap water). For hard water, dilute 6:1.

Water for All-Grain Brewers

All-grain brewers will need about 12 gallons (45 L) of water for their 5-gallon (19-L) batch of beer and they will need to consider the calcium ion content. Follow the dilution rates for soft, medium and hard waters given above, but make 12 gallons (45 L) of brewing liquor. Then, add 2.5 tsp of calcium chloride (CaCl2) to it. (Alternately, add 2.5 tsp of gypsum.) This should put your calcium and carbonate ions levels in the ballpark.

Pale Malts

A good International lager has a nice, pale malty/grainy character. To get this character, all-grain brewers should use 2-row Pilsner or lager malt as their base malt. If you want, you can also add around 0.25–0.50 lbs. (0.11–0.23 kg) of CaraPils malt per 5 gallons (19 L). This will add a little extra body to your beer. Keep in mind, though, that these are fairly light-bodied beers and the amount of body can also be influenced by your mash variables.

A small amount of acidulated malt — around 0.25 lbs. (0.11 kg) per 5 gallons (19 L) — may also be helpful. The pH of a mash made with pale malt in soft water may be a little higher than optimum and adding some acidulated malt can lower it.

Extract brewers should select the lightest-colored, all-malt extract they can find. If you use liquid malt extract (LME), make sure it is fresh — stale LME will be darker than you want it to be. The real trick for extract brewers — especially stovetop brewers — will be to use procedures that will not darken the extract excessively during the boil. (See the recipe on page 40 for the details. See also “Extract Experi-ments,” in the October 2004 issue for more on brewing light extract beers.)

Corn to Lighten the Body

Like American Pilsners, International lagers use corn as an adjunct. However, since 2-row pale barley malt has fewer enzymes than the 6-row malt used to make American Pilsners, the percent of corn in International lagers is held to 20–25%, compared to the 30–40% used in American Pilsners. All-grain brewers have the options of using flaked maize, grits or brewers corn syrup as their adjunct; extract brewers can only utilize brewers corn syrup. (Note: Supermarket corn syrup often contains vanilla. If your local homebrew shop doesn’t carry brewers corn syrup, do an Internet search for “brewers corn syrup” or “brewery grade corn syrup.”) The adjunct lowers the body of the beer and decreases the level of protein in the wort, but does not lend a strong corn flavor to the beer.

Neutral Hops

International lagers have a light hop bitterness (around 20–25 IBU) to balance the malty and sweet flavors in the beer. Any “neutral” bittering hop will work well. For a finishing hop, Saaz is a popular choice.

Lager Yeast

Ferment your International lager with lager yeast. Good choices are Wyeast’s 2024 (Danish Lager), 2247 (European Lager) or 2124 (Bohemian Lager) or White Labs WLP830 (German Lager), WLP850 (Copenhagen Lager) or WLP940 (Mexican Lager) yeasts.

To raise enough yeast for a healthy fermentation, make a 2–3 quart (~2–3 L) yeast starter at a specific gravity around 1.035. (You’ll need 6–9 oz. (170–255 g) of dried malt extract for this.) As you will be fermenting a relatively adjunct-rich wort in very soft water, it might pay to make your yeast starter with tap water and add some yeast nutrients (around 1/8 tsp per starter). Once the starter has fermented, pitch only the yeast sediment.



Most (probably all) International lagers are made by a process called high gravity brewing. In it, the brewer ferments a strong beer then dilutes it to working strength before packaging. Commercial brewers make their strong beer around 14–16 °Plato (OG 1.056–1.064), for a beer around 6–7% ABV. This beer is diluted so that the original gravity would have been around 10–11 °Plato (1.040–1.044 virtual OG), for the final 5% ABV beer. For a homebrewed International lager, you can make 5 gallons (19 L) of beer at around 6% alcohol by volume (ABV) and dilute it to 6 gallons (23 L) at around 5% ABV. The all-grain recipe accompanying this article follows this plan. The beer from the extract recipe will not be diluted.

Mash (and cereal mash)

All-grain brewers can either add flaked maize to their mash or do a cereal mash using corn grits. (See the March-April 2005 BYO for more on cereal mashing.)

A single infusion mash at 148–150 °F (64–66 °C) will work fairly well, especially if you are using only pale malt and flaked maize (i.e. no CaraPils malt). However, a step mash will give you a more highly-fermentable wort that is more appropriate for the style.

One easy way to do this is to mash in your kettle. Mashing in your kettle allows you to apply direct heat to the mash to raise the temperature between rests. Be sure to stir well as you heat, though.

Here’s a mash program that has worked well for me when making light lagers. Mash in at 131 °F (55 °C), with a mash thickness of about 1.5 quarts of water per pound of grain (13 L/kg), and hold at this temperature for 10–15 minutes. If you are using flaked maize, include it with the grains at mash in. If you are doing a cereal mash, begin that immediately after mashing in. After the rest at 131 °F (55 °C), heat the mash to 140 °F (60 °C), stirring almost constantly. While heating, raise the temperature a couple of degrees Fahrenheit (one degree Celsius) per minute. Hold mash at 140 °F (60 °C) for another 15 minutes. Then, stir in your cereal mash (if you used grits) and add heat to raise temperature to 152 °F (67 °C). Hold here for 45 minutes. Finally, heat your mash to 170 °F (77 °C) and transfer it to your lauter tun. (The temperature will drop a few degrees, unless you’ve heated your lauter tun.) Let the mash sit for 5 minutes, then recirculate.

When you begin collecting wort, heat the sparge water to 180–190 °F (82–88 °C) to raise grain bed temperature to 170 °F (77 °C). Once the grain bed reaches that temperature, add some cool water to your hot liquor tank to bring it down to 170 °F (77 °C). Collect the wort over 90 minutes, stopping collection when either the specific gravity falls below 1.008 or the pH climbs past 5.8.

Boil Hard

All-grain brewers should boil the wort vigorously for 90 minutes. Adjust your burner so you get the proverbial full rolling boil and end up with 5 gallons (19 L) of wort. A vigorous boil will ensure good hot break formation and DMS (dimethyl sulfide) volatilization. Add a pinch of calcium (less than 1/16 tsp CaCl2 or gypsum) at the beginning of the boil — this will help with your hot break, lower your wort pH slightly and keep wort darkening to a minimum. One or two teaspoons of Irish moss added in the last 15 minutes of the boil will help with clarity.

In the extract recipe, the total boil time is 60 minutes. For the first 45 minutes, only the wort from the partial mash, along with some dried malt extract, is boiled. Liquid malt extract (LME) is added for the final 15 minutes of the boil — decreasing the amount of wort darkening associated with boiling a “thick” wort.

Cool Quickly

Cool your wort as quickly as is feasible to fermentation temperature. In beers made from very pale malts, DMS can be a problem if the wort is cooled too slowly. DMS adds a cooked corn-like flavor to beer and most brewers strive to avoid this.

Extract brewers should cool their wort before transferring it to their fermenter. Although it’s easy to dump hot wort into cold water to cool it, if hot wort splashes around too much it will darken. Cool the wort either in your sink or with an immersion wort chiller.


For best results, ferment your International lager within the usual lager fermentation temperature range — 48–56 °F (9–13 °C). When primary fermentation is complete, or nearly so, let the temperature rise to 60 °F (16 °C) for a diacetyl rest. Diacetyl will give beer a buttery or butterscotch-like off flavor. A one or two day rest should be fine, but taste a sample of the beer to be sure.

The final specific gravity of most International lagers is in the 1.005–1.007 range, with the strong beer being correspondingly higher. In the all-grain recipe, your strong beer should finish fractionally above 1.007 and end up at 1.006 upon dilution.

Lagering Length

Commercial lagers are not lagered for long — around three weeks is fairly common. Filtering the beer helps speed the lagering process, though. Therefore, for unfiltered homebrew, lager a little longer (around 5–6 weeks) for the beer to get past the green stage.


Clarity is important in this style of beer. If you have a filter, this would be the type of beer to use it on. If not, add Polyclar AT to your lagered beer the night before you bottle or keg it. This fining agent will drag excess haze-causing tannins in the beer to the bottom of your secondary fermenter. For 5 gallons (19 L) of beer, stir 2 tsp. of Polyclar into a couple ounces (~60 mL) of water that has been boiled, then cooled to room temperature. Dump this mixture in the beer and stir quietly a couple times with a sanitized spoon. The Polyclar will settle out within about 6 hours and be left behind when you rack the beer.

If you did not use the high gravity method, just bottle or keg it as you usually would. If you made 5 gallons (19 L) of strong beer, dilute it to 6 gallons (23 L) of working strength beer with one gallon (3.8 L) of distilled, deaerated water. To make deaerated water, boil 1.5–2 gallons (5.7–7.6 L) of water hard for 15 minutes. Cool this water quickly, without splashing it, to at least room temperature. (If you have a keg carbonation stone, you may want to bubble CO2 through the water for a minute or so once it has been cooled.) Quietly siphon one gallon (3.8 L) of this water to your bottling bucket or keg, then siphon your strong beer into it. If bottling, stir the beer lightly before you begin filling bottles.

If you’re kegging, 6 gallons (23 L) can be an inconvenient amount. One option is to bottle five 22-oz. (650 mL) bottles of your strong beer first. Next, dilute the remaining 4.16 gallons (15.7 L) of 6% ABV beer to 5 gallons (18.9 L) of 5% ABV beer. This way you have a Corny keg, and a few bomber bottles of malt liquor on the side.

International lagers are fairly fizzy, so bottle with 1 cup of corn sugar per 5 gallons (19 L) or adjust the temperature and pressure of your kegging system to obtain around 2.6 volumes of CO2 per volume of beer.

Enter the Skunk

If you want to be authentic to the bottled versions of International lagers available in the US, many of which have that “Euro skunk” aroma, put your beer in green bottles. If the bottles are exposed to sunlight or UV light, they will skunk. If you prefer your beer unskunked, put it in brown bottles.

A Dry Finish

Given that you can’t completely exclude oxygen from your dilution water at home, drink your beer within 2–3 months or if it begins to show signs of oxidation.


Grab My Heinie

(undiluted base beer)
(5 gallons/19L, all-grain)
OG = 1.053 FG = 1.007
IBU = 25 SRM = 5 ABV = 6.0%

(post-dilution — 6 gallons/23L)
virtual OG = 1.045 FG = 1.006
IBU = 21 SRM = 4 ABV = 5.0%

8.0 lbs. (3.6 kg) 2-row Pilsner malt
5.0 oz. (0.14 kg) Weyermann acidulated malt
4.0 oz. (0.11 kg) CaraPils malt
2.4 lbs. (1.1 kg) corn grits
2 tsp Irish moss
1/4 tsp yeast nutrients
6.6 AAU Magnum hops (60 mins)(0.41 oz./12 g of 16% alpha acids)
0.13 oz. (3.5 g) Saaz hops (15 mins)
Wyeast 2024 (Danish Lager) or White Labs WLP850 (Copenhagen Lager) yeast (3 qt./~3 L yeast starter)
2 tsp. Polyclar AT (fining agent)
1 gallon (3.8 L) deaerated water (for blending)
1.25 cups corn sugar (for priming)

Step by Step
Heat 12 quarts (11 L) of water to 142 °F (61 °C) in your kettle. Set aside 1.0 lb. (0.45 kg) of Pilsner malt. Mash remaining grains at 131 °F (55 °C). Make cereal mash by combining 5.0 quarts (4.7 L) of water with grits and 1.0 lb. (0.45 kg) Pilsner malt, heat to 158 °F (70 °C) and hold for 5 minutes. Then heat to a boil, stirring constantly. Boil cereal mash for 15 minutes. After main mash has rested 15 minutes, begin heating it to 140 °F (60 °F). Stir this mash as well. (It helps to have a brewing partner.) Hold main mash at 140 °F (60 °C) for 15 minutes. Stir cereal mash into main mash and adjust temperature to 152 °F (67 °C). Hold for 45 minutes, then heat to 170 °F (77 °C). Transfer mash to lauter tun and recirculate wort for 20 minutes, then begin running off wort. Sparge with 190 °F (88 °C) water until the top of the grain bed reaches 170 °F (77 °C), then sparge with 170 °F (77 °C) water. Boil for 90 minutes. Add a pinch of calcium (CaCl2 or gypsum) at the beginning of the boil. Add hops at times indicated in recipe. Add Irish moss and yeast nutrients with 15 minutes left in the boil. After boil, cool quickly and transfer to fermenter. Aerate and pitch yeast sediment from yeast starter. Ferment at 53 °F (12 °C) until terminal gravity is within 3 “gravity points” of final gravity. Let temperature rise to 60 °F (16 °C) for a diacetyl rest. Cool to 30–40 °F (-1.1–4.4 °C) and lager for 4–6 weeks. Add 2 tsp Polyclar AT to beer the night before you keg or bottle it. Dilute to 6 gallons (23 L) of finished beer by blending base beer with 1 gallon (3.8 L) of deaerated water. Package in keg or green bottles.

Grab My Heinie

(5 gallons/19L, extract with grains)
OG = 1.045 FG = 1.006
IBU = 21 SRM = 4 ABV = 5.0%

2.0 lbs. (0.91 kg) 2-row Pilsner malt
13.6 oz. (0.39 kg) Laaglander Light dried malt extract (DME)
2.5 lbs. (1.13 kg) Coopers Light liquid malt extract (LME)
1 lb. 7 oz. (0.65 kg) brewers corn syrup
1 tsp Irish moss
1/4 tsp yeast nutrients
5.4 AAU Magnum hops (60 mins) (0.33 oz./9.6 g of 16% alpha acids)
0.10 oz. (2.8 g) Saaz hops (15 mins)
Wyeast 2024 (Danish Lager) or White Labs WLP850 (Copenhagen Lager) yeast (2 qt./~2 L yeast starter)
1.5 tsp. Polyclar AT (fining agent)
1.0 cup corn sugar (for priming)

Step by Step
Put crushed Pilsner malt in a nylon steeping bag. In a large (8 qt./8 L or bigger) kitchen pot, heat 3 qts. (~3 L) of water to 169 °F (76 °C), turn off heat and dunk steeping bag. Steep grains for 45 minutes. If steeping temperature falls below 148 °F (64 °C), heat slowly to 158 °F (70 °C). (This is actually a partial mash, so follow temperatures and liquid amounts closely.) While grains are steeping, heat 2.0 gallons (7.6 L) of water to 180 °F (82 °C) in your brewpot. When steep is over, add 2 quarts (~2 L) of hot water from kettle to the “grain tea” in the steeping pot. Remove grain bag and place in colander over brewpot. Pour the diluted “grain tea” through the grains in the steeping bag. Discard grain bag, add DME and corn syrup to the liquid in the kettle and bring to a boil. Once the foam subsides, add hops and begin the 60 minute boil. With 15 minutes left in boil, add Saaz hops, Irish moss and yeast nutrients, then turn off heat and stir in LME. Resume heating once LME is completely dissolved. (Keep boil clock running.) After boil, cool wort quickly and transfer to fermenter. Add water in fermenter to make 5 gallons (19 L). Follow remaining all-grain instructions, except for dilution to 6 gallons (23 L).

Issue: July-August 2005