April 18, 2018

Update and Blend of Spontaneous Beers from November 2016 and January 2017

With the move to Denver inching closer every day I'm running out of time to give my last few sour beers the kind of bulk aging time I want. Especially the two lambic-ish spontaneous beers I brewed in November 2016 and January 2017. For ease of reference I'll refer to these batches as spontaneous beer 1 (November 2016) and spontaneous beer 2 (January 2017). I haven't done a good job of noting anywhere that I've added a few tasting notes from samplings but there are some notes on their respective posts. Neither beer is exactly successful but neither are complete misses. I want to see what happens if I bottle and continue to age the beers. I also have some thoughts on the coolship process for these small batch spontaneous fermentations that probably apply on some level to batches in the five to ten gallon range more common for my fellow homebrewers.

Quick overview on the process behind these beers

The primary goal for these beers is to test whether I could spontaneously ferment small batches which will allow me to create several base beers to blend within a reasonable volume. I modeled these beers reasonably close to lambic production techniques. Both beers were turbid mashed, used aged hops and coolshipped. The grain bills are very similar except I used pale malt over pilsner because I had a sack of pale malt on hand.

For the coolship procedure I first put the beer out in the boil kettle. As it approached 130F I preheated my small batch two gallon mash cooler and transferred the wort to the cooler for the remainder of the cooling process to slow the rate of cooling. This is atypical for lambic production but with the small volume of wort I had concerns the wort would cool too quickly to gain good innoculation.

Here is the rate of cooling for spontaneous beer 1:


And here is spontaneous beer 2:


The good news is that the cooling rate was fairly repeatable with this process. While both batches fermented out just fine, neither developed any meaningful sourness.

Results of spontaneous beers 1 and 2



Both beers developed interesting flavor but completely lack sourness, surprisingly. My suspicion for the cause of the resulting beers is that neither spent enough time in the bacteria-friendly zone (90-120F) and more time in yeast-friendly temperatures (40-90F). The fix, if this is true, is to get the beer to cool even slower through the mid-range temperatures with an end temperature closer to 60-65F. So once I'm set up in Denver to start brewing I'll change my approach and test cooling at ambient temperature closer to 55F and see if that makes an improvement.

Let's get back to the beers at hand.

Spontaneous beer 1 is actually coming around pretty nicely. It has a huge brett barnyard funk but as that fades I'm rewarded with orange, lemon, dustiness, minerality and a touch of acidity that wasn't there a few months ago. The orange flavor is pretty cool. I don't think I've ever experienced such a clear orange flavor in a sour beer.

Spontaneous beer 2 has taken a weird turn. Just a few weeks ago the beer was developing a nice cherry pie flavor with a little acid. Today it tastes watery and empty. Like all the flavor, all the body and all the acidity just left behind some mushroom-y flavor, a little mineral and a moderate punch of lingering tannins. What happened to this beer? No idea. Hard to believe this is even the same beer. Like a mushroom flavored Topo Chico. Hopefully this is just a phase that will turn around soon. It's just started to get consistently warm so maybe that is the motivating factor here.

If I did not want to treat these beers as experiments I'd bottle beer 1 and hang on to beer 2 to see if it comes back around but would otherwise probably dump it.

Blending spontaneous beers 1 and 2

Given that these beers are going into bottles mostly for the sake of seeing how they develop, I took the lazy approach and blended for volume over flavor. I made a 50/50 blend of the two beers to produce the greatest number of bottles. I tasted the blend before committing to it and felt it was decent enough to blend, not really knowing what might happen as the beers get time to fully mature. While I could have bottles these separately, blending them adds another opportunity to explore how two fairly different beers might play against each other in the bottle.

Despite being a 50/50 split, beer 2 really dominates somehow. Like the watery flavor and texture of beer 2 dilutes everything about beer 1 which is somewhere in the background but completely oppressed. If I didn't know better I would think the blend is 90% beer 2 and 10% beer 1. Something weird is definitely going on with beer 2.

The beers were bottled into 750ml bottles with priming sugar targeting four volumes of CO2. I'll probably wait until late summer to check in on these bottles out of hope there is some lazy LAB that will sour the beer in another home.

Lessons learned with these batches

Overall these beers are encouraging that I'm heading in the right direction from earlier, worse attempts to spontaneously ferment lambic-style wort. The greatest lesson for me is to continue working on temperature as a factor in the coolship process. Thankfully Denver has a lot of cool nights so finding an evening even in May or June might be feasible for an early coolship experiment. 

Additionally, I feel the use of aged American hops worked well enough in these beers. I will probably play around with hopping rates in the future to strike the right balance between residual hop character and excessive bitterness or tannins. I look forward to my homegrown hops growing better in Denver and producing hops I can age and experiment further with how different hop varieties might result in different flavor in spontaneous beer. 

A question for the readers:

Have you ever experienced a sour beer go flavorless and watery out of nowhere like this? If so, did it improve? What do you think caused it? 

I have experienced something like this once. Early in my homebrewing days--I don't think this beer even made it to the blog--I had the terrible idea to brew a brown ale and add amaretto liqueur to it to get an almond flavor. The beer was fine when I added the amaretto but by the time it carbonated in the bottle it just tasted and felt completely empty, much like beer 2. Like 90% carbonated water and 10% brown ale. So weird. In that case I don't think it was an infection from the amaretto but I could be wrong. No amaretto was injured in the making of this spontaneous beer. 

2 comments:

  1. Interesting post. Sorry to hear the beers were bland. Have one of my own (6 months old) that I haven't tried yet - your experience will help set my expectations.

    For the lack of sourness I wonder if lack of early lacto acidity or lack of late pedio acidity is more to blame.

    Lambic production is almost like black magic. It seems like spontaneous fermentation must only be part of the story. The years of microbe selection they've been doing is probably the key to everything.

    I've had similar experiences to what you describe - beers seeming to change flavor over night. I've come to suspect that my mind and palate have the potential to play tricks on me. Humans (or at least this human) do not possess scientific grade flavor measuring equipment.

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  2. It's just part of learning how to do this process right, especially at such a small level. I tasted a low fill bottle of the blend last weekend and it's already more sour but also has a really sharp barnyard flavor that reminds me of taking samples of sour or brett beers too close to the pellicle. When I taste that in beer I usually see positive development follow so I remain optimistic.

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