Souring post fermentation

[FrancoBrews10]

Hi guys. We host about 20 people at our house for xmas every year, so I always try to have a some different brews so everyone can have a chance to enjoy what they like. Among the 6 brews, I realized at one point that I brewed 3 wheat beers (honey weizen, lemon shandy, and a raspberry wheat). In order to break that up I figured since the raspberry is in primary and hadn't yet added the raspberry extract to I could probably turn it into a sour and rack on top of mixed berries in the secondary. Obviously then finding out that I can't back sour.

However, I have an idea. I've got 3 cans of fast pitch leftover, in theory I could do a heavy sour to that wort, kill the lacto, and then use it as mix it into the 5 gallons?

Things I dont know: How will it affect the abv?, will it create a co2 bomb? Should I do that and use it as priming? I will be kegging this so bottle bombs are not a factor

 

[Beerswimmer]

As long as the raspberry isn't hopped yet.

 

[RPh_Guy]

You have plenty of time to brew a sour by Christmas.

I wouldn't recommend messing with your current beer.

 

[FrancoBrews10]

As long as the raspberry isn't hopped yet.

Already hopped.

 

[FrancoBrews10]

You have plenty of time to brew a sour by Christmas.

I wouldn't recommend messing with your current beer.

For the sake of science?

 

[Beerswimmer]

It won't sour.

 

[RPh_Guy]

@Beerswimmer is correct.

Hops inhibit the type of bacteria that can sour a beer this quickly.

The only way to make it sour at this point is to directly add acid. I don't recommend this approach; many people say it lends a chemical taste.

You can make sour beer as fast as any ale. Check out this thread:
https://www.homebrewtalk.com/forum/threads/fast-souring-modern-methods.670176/

Cheers

 

[FrancoBrews10]

Already hopped.

Right. This is why I want to ferment new wort, and then add it to the beer.

 

[Funky Frank]

Go for it!

Combine your fast pitch and mixed berries and maybe some table sugar to make a 1 gallon “batch.” Pitch Lacto and pure Brett(if you have access) and keep it warm for a week. This should make it puckeringly sour and the Brett takes about a week to start fermenting so it should be ready to run. Add to 5 gal batch, wait a week and keg.

I have never done this exact thing myself so this is just an idea.

Please update us on whatever you decide!

 

[Funky Frank]

You could also or alternatively bump up the acidity with a mix of lactic acid and tartaric acid (give a wine vibe) or lactic acid and citric acid (for a sangria vibe) if you’re afraid of acid additions tasting one-sided and artificial. Or find some very acidic fruit like a lot of commercial brewers do.

 

[RPh_Guy]

Combine your fast pitch and mixed berries and maybe some table sugar to make a 1 gallon “batch.” Pitch Lacto and pure Brett(if you have access) and keep it warm for a week. This should make it puckeringly sour and the Brett takes about a week to start fermenting so it should be ready to run. Add to 5 gal batch, wait a week and keg.

I have never done this exact thing myself so this is just an idea.

I'm not sure this would work. The pH may be too low for the Lacto to work, and whatever acidity is created will be diluted by a factor of 6 when blending with 5 gallons.

If he's going to brew a new beer for blending I don't why why he wouldn't just make a full batch the right way.

 

[Funky Frank]

It’s just what he wants to try. The best way to make a sour is probably to make a sour but if he wants to try this, why not?

This experiment could make an approachable (for sour newbies) sour that compliments the fruit. It might also turn into a dumper or something in between. My money would be on the better side of that spectrum but it’s just a bet.

I did some quick-n-dirty math for the dilution. A 1 gallon solution of pH3.0 added to a 5 gallon solution of pH7.0 would yield a 6 gallon solution of pH4.3. This of course does not take acid strength into consideration or buffering potentials. Your 1 gallon batch won’t get down to 3.0 but your clean ale is likely already between 5.0 and 6.0. Is it going to make a sour warhead, no. Is it going to make a nice approachable sour, maybe.

 

[RPh_Guy]

I did some quick-n-dirty math for the dilution. A 1 gallon solution of pH3.0 added to a 5 gallon solution of pH7.0 would yield a 6 gallon solution of pH4.3. This of course does not take acid strength into consideration or buffering potentials. Your 1 gallon batch won’t get down to 3.0 but your clean ale is likely already between 5.0 and 6.0. Is it going to make a sour warhead, no. Is it going to make a nice approachable sour, maybe.

We do not taste pH.
We do taste the amount of acid (and its salts), which is a linear dilution when blending, not logarithmic.

FYI a finished beer is typically between pH 4.0 and 4.5.

The OP can certainly do whatever. I'm just offering advice.

Things I dont know: How will it affect the abv?, will it create a co2 bomb? Should I do that and use it as priming?

If you do move forward with creating a small sour batch and blending (which I don't recommend), you should let the sour wort ferment with yeast either before or after blending.
You'll need to use a simple blending calculation to determine the ABV unless the OG is the same for both batches.

I'm not sure what you're asking about with regard to CO2 bombs or priming.

Also what's a "can of fast pitch"? Are you talking about Lallemand Sour Pitch.

 

[Funky Frank]

FYI a finished beer is typically between pH 4.0 and 4.5.

You’re right. My numbers were wort not beer.

Fast pitch is a commercial canned starter wort sold by Northern Brewer.