Following a method outlined by a podcast I listened to last year, BasicBrewingRadio from July 26, 2012 and the link from that show to Sean Coates blog here, I set myself up to brew a sour mash Berliner Weiss.
There seems to be two keys to pulling this off:
- A way to get a CO2 blanket on top of the souring mash
- A way to keep the mash around 120F for the length of time you want to sour it (1-3 days)
The basic method is this.
- Using a basic wheat beer malt bill, and shooting for a low SG, mash your grain as normal. I used a cooler and just let my mash sit in it until it reached 120F the next day. Once it did reach that temp I threw in 1 pound of unmilled 2-row which inoculated the mash with the lactobacillus that naturally is on all malted grain. Every 6-8 hours or so I added some boiling water to get my mash back to 120F. My garage was cool at this time, if it is summer and you live in a warm climate you may be able to maintain 120F in a cooler for an extended period of time.
- Once I added the boiling hot water, stirred, I then blew a little CO2 on top of the mash as I closed the lid. This removed the oxygen from the top of the mash which then helped prevent other ‘bugs’ from taking over. The kind that smell like feces, vomit etc. By doing this, my mash never really ‘stunk’ like others have reported, but it had a STRONG, and I mean strong cooked canned corn smell.
- After 36 hours my sample tasted sour / tart enough and I drained the first running’s, and batch sparged as normal.
- I boiled for 30 minutes, and added a touch of hops at 15 minutes to get me to around 5-6 IBU’s.
- The rest is a normal batch of beer, and the advantage of this method is that I don’t have ‘bugs’ that are on the cold side, so I can treat it like any other brew. I did my ferment after cooling down with US-05 and let it sit for a few weeks prior to kegging.
Recipe: Sour Mash Berliner Weiss
Style: Berliner Weiss
TYPE: All Grain
Boil Size: 6.12 gal
Post Boil Volume: 5.98 gal
Batch Size (fermenter): 5.00 gal
Bottling Volume: 4.60 gal
Estimated OG: 1.040 SG
Estimated Color: 3.0 SRM
Estimated IBU: 8.4 IBUs
Brewhouse Efficiency: 72.00 %
Est Mash Efficiency: 82.8 %
Boil Time: 15 Minutes
Amt Name Type # %/IBU
4 lbs 4.8 oz Pale Malt (2 Row) US (2.0 SRM) Grain 1 58.9 %
3 lbs White Wheat Malt (2.4 SRM) Grain 2 41.1 %
1.00 oz Hallertauer Mittelfrueh [4.60 %] – Boil Hop 3 8.4 IBUs
1.0 pkg Safale American (DCL/Fermentis #US-05) Yeast 4 –
Mash Schedule: Single Infusion, Light Body, No Mash Out
Total Grain Weight: 7 lbs 4.8 oz
Name Description Step Temperat Step Time
Mash In Add 9.13 qt of water at 163.7 F 149.0 F 60 min
Sparge: Fly sparge with 4.96 gal water at 168.0 F
Mashed at 1.5qt/lb at 149F, let drop to 120F and then added 1 lb unmilled 2-row.
Let sour for 36 hours, boiled 30 minutes and added hops at 15 minutes
1 pkg US-05 at 63F