|Grain Bill: 50% Wheat Malt 50% Pils|
This weeks beer is a wonderful summer beer that can go from mash tun to glass in as little as a week. This style is rarely found outside of Berlin, despite having a long-lasting reputation as the “champagne of the north”; an appellation provided by Napoleon’s troops during their conquest of Germany.
Berliner Weiss (or Weisse) is a deceptively simple sour beer. Its key characteristic is a taste-forward sourness, provided by ample quantities of lactic acid. Low in alcohol, effervescent and dry, with a lactic acid pucker, this beer is great for hot days, patios & BBQs. Its intense sourness is not enjoyed by all, so it is commonly served with simple syrup (‘mit schuss’) or flavoured with either woodruff (‘waldmeister’) or raspberry (‘himbeer’) syrups. It is often considered the most refreshing style of beer.
|Warming the mash water|
Berliner Weiss recipes are simple; all start with a 50/50 mix of Pilsner and Wheat malts, and some add in a bit of table sugar to dry out the beer. Minimal hop flavour/aroma is provided by a light hopping with German hops. Starting gravities are typically 1.028 – 1.032, producing an alcohol content of 2.8-3.5%. From here the style can remain simple, or get quite complex. Lactic acid bacteria like lactobacillus or pediococcus are used to provide a strong dose of lactic acid, while neutral ale yeast ferment out the beer. Some feature a mild Brett character which adds a hint of fruitiness and funk to the beer.
There are two major ways Berliner Weiss can be brewed – a classical sour ferment, or a more modern sour mash. Sour ferments are the same as for Belgians sours: months-to-years in duration, complex, and unpredictable. Sour mashes are the polar opposite – and an excellent entry point for a brewer interested in sour beers. Instead of relying on souring organisms in the ferment, a sour mash instead introduces them into the mash. Over a few days the mash sours, after which the sparge and boil kill these organisms. The beer can then be fermented with a clean ale yeast, kegged, and be ready to drink in as little as 7 days after the mash is started.
|A cooled mash, innoculated with
uncrushed Pilsner malt.
Sour mashing is a simple process, and one which allows sour beers to be produced without the long ferments and separate fermenters/siphons/etc that is typical of a sour ferment. To begin a sour mash, dough-in as normal, but using the smallest amount of water possible (I used 2L/kg; roughly 1pt/lb). Instead of sparging, the mash is cooled to ~40C, at which point a small amount of uncrushed malt is mixed into the mash, thus dosing with some wild lactobacillus. The mash is then sealed from oxygen under a layer of CO2 or tin foil, and allowed to sour.
|A sour mash, insulated with
sleeping bags and monitored
with a meat thermometer.
The mash temperature needs to be maintained at 30-35C for the ~48 hours it takes to sour the beer; if a heating system (electric smoker, hot tub, etc) is not being used, the mash needs to be checked every 8 or so hours, and if cool, boiling water added to bring the temperature back up (this is why we use a minimal-volume mash).
Sour mashing requires three things to work well – temperature, CO2 and tasting. At these warmer temperatures, harmful and bad-tasting bacteria are inhibited, while the lactobacillus will be growing at an optimal temperature. These characteristics are aided by the absence of oxygen, provided by the CO2 or foil blanket covering the mash. Finally, by tasting the mash (usually starting at 24 hours, and every 4-8 hours after that), the souring process can be stopped when the desired sourness is achieved.
You will not want to taste the mash. The aroma is horrific, and every instinct in your body will rail against tasting the mash liquid. But do not fear – the lacto is not harmful (some strains are even probiotic), and the aroma does’t reflect the taste.
Brewing the Summer Sour:
|An hour with the lid open
and it still too warm!
|The first runnings|
Check back in a week or two for the tasting notes!
|Type: All Grain||Date: 13-05-30|
|Batch Size (fermenter): 20.00 l||Boil Time: 15 min|
|Boil Size: 22.75 l|
|Est Original Gravity: 1.030 SG||Measured Original Gravity: 1.032 SG|
|Est Final Gravity: 1.008 SG||Bitterness: 8.8 IBUs|
|Estimated Alcohol by Vol: 2.9 %||Actual Alcohol by Vol: 2.9 %|
|Est Color: 2.7 SRM|
|Mash Name: Single Infusion, Light Body, No Mash Out||Total Grain Weight: 3.00 kg|
|Sparge Water: 19.46 l||Grain Temperature: 19.0 C|
|Sparge Temperature: 75.6 C||Tun Temperature: 18.0 C|
|Mash PH: 5.20|
|Sparge Step: Batch sparge with 2 steps (Drain mash tun, , 19.46l) of 75.6 C water|