Dunder experiment part 2

[Al The Chemist]

New experiment is to create a controlled infection muck-pit. 

I’d love to hear your folk’s thoughts. My hope is to create a controlled bacterial infection that I experiment with adding during different phases of the fermentation. I’m going to avoid using any Clostridium butyricum as butyrates are nasty to handle and I am fine sticking to butyric acid. 

In looking for a good alcohol tolerant lactic acid bacteria, I tried Penicillium roqueforti but the acid production was quite low. Next on my list is Lactobacillus rhamnosus. 

I’m curious about proponibacterium, but have not been able to find a palace to source any. 

Any other ideas of what could be interesting to add to the mix?

[Silk City Distillers]

Proprionibacterium Shermanii is what gives Swiss and Gruyere  its "eyes".  I like the Biena brand, you can find it everywhere online, including Amazon.

For Clostridium, the only recommendation I'd make is Miyarisan probiotic from Japan, it's sold as a human dietary supplement and has had rigorous testing for consumption.  Botulinum toxin is not how you want to spend a weekend.  You need to propagate this in a medium that's conducive to that, before pitching.  Miyarisan is spores, so it needs to germinate and grow.

If you hunt around enough in journals or online you'll find strategies to prop these.

[Silk City Distillers]

For LAB, my preference is Brevis from White Labs.  While it's not a prolific acid producer like others, it skews heavily towards Lactic, without a lot of acetic.  Like I said above, we don't need more acetic acid.  It also produces less acetaldehyde and diacetyl than others.  It does produce ethanol, so it has better tolerance than those who don't, but there are not many strains that can be pitched into fermented wash effectively.  That said, brevis is a common strain involved in beer spoilage, which means it's happy to produce acid in lower-alcohol environments.

Sequence matters significantly, if you pitch LAB before yeast, you'll produce significantly more lactic acid before you hit terminal acidity (sour).  If you pitch yeast first, and want to rely on late lactic activity for souring, you are going to take a long time (you'll be fermenting for weeks beyond terminal gravity).  

 

[Al The Chemist]

Thanks @Silk City Distillers! I'll start looking into sources. 

I've worked with the Miyarisan probiotics, but like you mentioned. Between the general risk of Botulism and the overall nasty smell, I'm happy working with the concentrated acid

Point well taken on the pitching time. I'm aiming to run a side fermentation in a diluted rum wash that will be consistently fed and used. I hope some of the concentration will already be there once I add to the main wash. The plan is to indeed let the fermentation sit for another couple of weeks.  

[Al The Chemist]

I’m not having much luck with Biena Proprionibacterium Shermanii. I’m wondering if my wash/medium is not conducive for its growth. There is not much info out there to its ideal conditions as it is assumed it will be used on milk/cheese. 

I currently have it in a backset/panella mix at just around S.G. 0.035. It's been 72 hours, I see no activity and when taking a sample I see no evidence of bacterial growth. 

I figured I’d pitch it before the Brevis as I expected the Brevis would feel more at home in this environment and didn't want it to out compete. 

Any advice?

 

Update: afer an additional 12 hours I am starting to see bacterial activity in a sample. PH dropped by 0.3. Looks like it took!