Malting and brewing process of Schlenkerla Smoked Beer

Brewing Smoked Beer

Germination of the "green" malt

The art of brewing beer has been known for thousands of years. Over the time the process of brewing has been continuously improved; this development has not yet reached an end. In the following, we would like to show you the way from barley to Original Schlenkerla Smokebeer brewed according to the Bavarian Purity Law of 1516.

Malthouse

It is not possible to brew beer directly from barely; first it has to be processed into malt. This happens in the Schlenkerla Brewery's own malthouse.

Kilning the malt with open fire

1st Step: Steeping

First the barley has to be soaked in water in order to start the germination process. In the language of brewers this is called "steeping". During this process, the grain is alternately steeped and aerated.

2nd Step: Germination

After the water content in the grain has reached 35%, it starts to germinate. When the grain begins to grow, enzymes are formed, which are able to break down the contents of the grain (mainly protein and starch). This ability is necessary later on in the brewing process. During the 7-day germination period the green malt, as brewers call it, is constantly turned and aerated.

Lagering of beech wood logs

3rd Step: Kilning

In order to stop germination and to stabilize the involved biochemical processes, the green malt must be dried (kilned). That is where the secret of the Original Schlenkerla Smokebeer lies. A beechwood log fire underneath the kiln heats the air, and the smoke gives the malt its typical smoky flavor.

Result: Schlenkerla Smoked Malt

This traditional way of making smoked malt is nowadays only done by two breweries in the world: Schlenkerla and Spezial of Bamberg. Slow Food® has therefore listed both in their Ark of Taste.

Breweries without their own malthouse - the vast majority - can purchase different types of malt from commercial malthouses. For them the brewing process starts with Step 4.

Brewhouse

4th Step: Grinding

To continue the transformation process started in the malthouse, the malt must initially be ground into grist.

classic copper vessel brew house at Schlenkerla

5th Step: Mashing

The grist is mixed with water in the mash tun. In the resulting mash, the enzymes can convert the components of the malt. The most important step is the transformation of starch into malt sugars. This takes place at temperatures between 45°C and 77°C. A specialty at Schlenkerla: The mash is still prepared in the ancient decoction technique in which the mash is additionally boiled. This results in a richer and fuller flavor of the smoked beer. Decoction comes from a time when thermometers had not been invented yet and temperature adjustment was done indirectly through volume measurement (mash drawing with buckets). As this technique is more labor and time intensive than modern mashing forms it is nowadays seldomly used in breweries.

6th Step: Wort Separation (Lautering)

After the conversion process is finished, the sugar-rich malt liquid, the wort, is separated from the solid components, the spent grain. The wort is then transferred to the brew kettle, while the spent grain is removed from the brewery, and can be used, for example, for baking bread.

7th Step: Boiling

The wort is boiled in the kettle and the hops are added in several stages. Through the heat the bittering elements in the hops are released, giving the beer its distinctive bitterness. During the boil, water evaporates so that the wort reaches the necessary concentration (original gravity). Some components of the wort become insoluble through the heat; these substances are called the "hot break" and must be removed subsequently. The overall process in the brewhouse from mashing to the completion of the boil takes about 8 hours.

8th Step: Cooling and Pitching

After boiling, the wort is pumped into the whirlpool; the wort is "drawn off", as brewers say. Here the hot break is removed. Subsequently the wort is cooled, aerated and yeast is added; in the language of brewers, it is "pitched".

Result: Wort

Fermenting Cellar

main fermentation

9th Step: Primary Fermentation

Yeast can survive not only through aerobic respiration (with oxygen, as the human body), but also in an anaerobic (without oxygen) environment through alcoholic fermentation. In this process, malt sugar is converted into alcohol, carbon dioxide and heat. At the end of primary fermentation, which lasts approximately 7 days, most of the yeast settles to the bottom of the fermenting tank. For this reason, it is called bottom-fermented beer. The yeast in top-fermented beer, i.e. Original Schlenkerla Smokebeer - Wheat, rises to the top of the fermenting tank. The green beer - which is what this interim product is called by franconian brewers - is now pumped to the lagering cellar for secondary fermentation.

Result: "green" (i.e. young) beer

Lagering cellar

century old rock cellars for smoked beer lagering

century old lagering rock cellars underneath Schlenkerla brewery

10th Step: Secondary Fermentation and Maturation

Now follows a period of maturation to perfect the beer. The remaining fermentable elements in the green beer are transformed by the yeast, whereby more carbon dioxide is created. The conditioning/storage tanks are closed with a prime regulator (a pressure release valve) which is set to a specific counter-pressure. In this way the carbon dioxide content in the final beer is regulated. Maturation takes about 6-8 weeks, after which the beer is ready to drink.

Another specialty of Schlenkerla:
The maturation takes place in the old caves underneath Stefansberg, which are part of an extensive tunnel system over 700 years of age. As they have a constant low temperature throughout the year, they have been used by brewers for centuries. Ice was harvested from lakes and rivers, to cool down the caves further and after warm winters, when not enough ice was available, it was even imported from as far as Finnland and Sweden to mature Smokebeer properly. Original Schlenkerla Smokebeer -Wheat does not mature in the lagering cellar, but in the bottle (Original Bottle Conditioning).

11th Step: Filtration

At the end of secondary fermentation, the beer still contains yeast and other suspended matter. It must be filtered in order to give it the brilliant clarity desired by the consumer. After that, it can be filled into either kegs or bottles.

Result: Smokebeer

filling of wooden barrels

Bottling and racking

Kegs and barrels:

After thorough cleaning and inspection, the kegs are filled under counter-pressure. Through pre-pressurization the beer flows into the keg without foam.

Another specialty at Schlenkerla:
following old tradition, the Smoked Beer in the Schlenkerla Brewery Tavern is still tapped exclusively from oak-wood kegs.