One Gallon Spontaneous Fermentation Beer Batch 5 Recipe and Brewday - Brain Sparging on Brewing


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November 16, 2019

One Gallon Spontaneous Fermentation Beer Batch 5 Recipe and Brewday

With the return of cool autumn weather it is time to resume my extended experimentation into spontaneous fermentation and lambic-like brewing. Early tastes of my most recent batches (spontaneous fermentation 3 and spontaneous fermentation 4) feel like I am moving in the right direction but continue to lack meaningful acidity. I do not want to create early 2010s American wild ale acid bombs but on the other hand some acidity adds structure and vibrancy to these beers. With this fifth batch of one gallon spontaneous beer I have opted to change the hops used to see if that better approaches this goal. (Read about batches one, two, three and four here). If nearby Crooked Stave and Black Project can make spontaneous beer just miles from my house then so there is no reason why I cannot figure out how to do the same thing on a smaller scale.

My thoughts on why my hop choice might be the reason for little to no acidity

In posts discussing the prior spontaneous batches I questioned whether my hopping rate explained the absence of acidity but continue to see the same issue arise despite adjusting down the hop rate. My earliest batches followed Cantillon hopping rates (0.65-75 oz./gal.) and produced no acidity at all. I dialed that down by half but still very little acidity. Conventional brewing knowledge says hops dwindle in alpha acids as they age and oxidize and surely six or seven year old hops should be too weak the stand up to lactic acid bacteria but that has not been my experience with these spontaneous beers.

Perhaps higher alpha hops never reach the low levels of alpha acids necessary to let LAB survive and acidify the beer. For prior batches I have used a combination of homegrown hops and Belma whole cones from 2011 which are plenty old at this point. I am sure those poorly grown homegrown hops are on the milder side of the alpha and beta acid profile but Belma clocks in around 10% alpha acids and 6% beta acids. Maybe over time these hops just do not dwindle as much as convention says they should regardless of time. I know there are commercial and homebrewers using moderate alpha hops in the 5-7% range with success but maybe there is an upper limit.

To test whether the hop choice is the culprit obviously I am testing different hops for this batch. Gone are the Belma hops and substituted in are some 3.5% alpha German Spalt Select pellets I picked up back in 2016 and have been aging since. For this batch I opted for a 0.40 oz/gal hopping rate with a combination of 0.25 oz Spalt pellets and 0.15 oz of 2015 homegrown cascades that oddly never browned.

One gallon spontaneous batch five recipe

This batch otherwise follows the same recipe as the other spontaneous batches. The turbid mash gets a little more manageable with each attempt and I feel like I can push through a turbid mash now about as easily as a more pedestrian infusion mash. A 50/50 split of root shoot pils malt and red wheat plus moderately mineralized water gets this beer to a ninety minute boil and then a lazy cool down under a couple aspen trees.

Batch size: 1.1 gallons
ABV: 4.4%
SRM: 3
Est. OG: 1.47
Est. FG: 1.002

Grain BillPoundsOuncesSRMPct. Grist
Pale Malt10250.00%
Unmalted wheat10150.00%
Water Profileppm
Yellow Bitter--Brussels
PH: 5.5
Water AdditionsMashSparge
Epsom Salt.4g.4g
Canning Salt
Baking Soda.3g
Calcium Chloride.3g.3g
Pickling Lime
Lactic Acid1.2ml

Mash schedule

Mash water volume: 1 gallon
Sparge water volume: 0.85 gallons

1. Begin heating all mash water
2. Dough in 25 oz at 131 for rest at 113F for 15 minutes
3. Raise mash water to boil
4. Add 25 oz boiling mash water to raise to 126F for 15 minutes
5. Remove 13 oz from mash and add to kettle #2. Raise and hold at 190F
6. Add 38 oz boiling mash water to mash to raise to 149F for 45 minutes
7. Remove 38 oz from mash and add to kettle #2. Continue to hold kettle #2 at 190F
8. Add remaining 38 oz mash water to mash to raise to 162F for 30 minutes
9. Begin heating sparge water to 190F
10. Transfer liquid in mash tun to kettle #3 and begin heating to boil
11. Add contents of kettle #2 to mash tun and rest for 20 minutes
12. Drain contents of mash tun to kettle #3 and continue to heat
13. Sparge as usual and combine all runnings

Boil schedule

90 minute boil
0.70 oz aged hops at start of boil

Obligatory first runnings pic

Cooling down the spontaneous beer

This batch followed the same approach of batches three and four of just cooling the entire time in the boil kettle. On the first two batches I tried transferring the wort to my small cooler mash tun to drag out the cooling but I am not sure I got anything meaningful out of that approach. Maybe that will be something to revisit in the future but for now I just toss the boil kettle out on a patio under the aspen trees and hope for the best. 

The cooling curve is to be expected although the interesting aspect here is that the warmer temperature had no real affect on the cooling rate over colder ambient temperatures. I would expect such a small volume of wort to reflect faster cooling in cooler temperatures. I guess that is what I get for having lousy scientific knowledge. 

Fermentation notes

Brewed 11.16.19. 


  1. Great project and very interesting/useful read. Thank you!

    Really interested to follow the progress of this one with the lower hopping rate. I've tried one a couple years ago that I, in retrospect, way over hopped (no sourness and bitter like a pale ale). Was planning on trying another - will be trying something similar with the aged homegrown low AA hops.

    Recently had the 3 Fonteinen Gueze after mostly drinking my own (non-spontaneous) sours and was very much struck by how much better theirs was than anything I've made. The acidity levels had just sort of slowly crept up over the years and I hadn't picked up on it. The Belgians know what they're doing for sure - finding a good way to replicate their hopping technique seems like a big part of capturing the magic.


  2. Thanks, I used this as a reference here!