Maintaining Mixed Cultures

Discussion in 'Brewing & Beer Knowledge' started by PhilT, Jun 12, 2018.

  1. PhilT

    PhilT

    Joined:
    Sep 28, 2016
    Location:
    Birmingham, England
    Interested to hear how folks here maintain their mixed cultures, do you use the sourdough method of periodically feeding the culture by decanting some and adding fresh wort? Do you use oak chips and transfer between batches? Or are you building up bottle dregs from previous batches? I've also heard of people just pouring a 750ml bottle into a 5 gallon batch and letting it go. Does this work?
     
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  2. reverseapachemaster

    reverseapachemaster

    Joined:
    May 21, 2015
    Location:
    Denver
    Many ways to do this. Personally I have a lazy approach of keeping slurry in Mason jars in my fridge. I decant and feed every few months if I haven't brewed with them in a while. I build it up in a starter before pitching. The cultures I use are acclimated to this process.
     
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  3. PhilT

    PhilT

    Joined:
    Sep 28, 2016
    Location:
    Birmingham, England
    When you say the cultures are acclimated do you mean they now perform consistently? I've been using a similar approach to yours and my culture is still evolving batch to batch, I'm hoping the dominant cultures will eventually come to the fore and begin to give me more consistent results.
     
  4. reverseapachemaster

    reverseapachemaster

    Joined:
    May 21, 2015
    Location:
    Denver
    Not only are they consistent in brewing but they are acclimated to my propagation and storage procedure. There's good science that brett and some LAB have lower vitality under cold conditions versus warm storage. My experience has been that my cultures remain consistent with cold storage in the fridge but they are slow to get to work and I probably do have low numbers when I feed them. I can accept all of that as true but I have learned my cultures and know I need a long lead time to propagate the culture before pitching. If I don't, at least with my sour culture, I get a nice batch of acetic acid. My cultures are weird mixes of commercial dregs that need a lot of rest time before I feel they are worth drinking. If I wanted faster cultures or more souring up front I would keep the cultures warm and feed more regularly.

    If your blend of organisms is fairly young then you might want to feed or propagate more frequently to advance the competition for dominance.
     
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  5. PhilT

    PhilT

    Joined:
    Sep 28, 2016
    Location:
    Birmingham, England
    Yeah mine is pretty young, cheers for the advice!
     
  6. TripleSixHoppia

    TripleSixHoppia

    Joined:
    Oct 30, 2013
    Location:
    Kentucky
    Same but I'm super lazy and just buy these EarthOx Sterile Centrifuge Tubes, that way I don't have to sanitize a jar. I just crack one open and add the slurry in.
     
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  7. rcubed

    rcubed

    Joined:
    Oct 6, 2013
    Location:
    San Diego, California
    I use DME or apple juice to feed my bugs. Which reminds me, they are overdue to get either fed to them right now.
     
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  8. Heins

    Heins

    Joined:
    Jun 15, 2018
    Location:
    Syracuse, NY
    How do you guys handle repitching mixed cultures without bacteria populations/acid dominating? Increase hopping? Cut the repitch with more Brett? Something else?
     
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  9. reverseapachemaster

    reverseapachemaster

    Joined:
    May 21, 2015
    Location:
    Denver
    I don't feed that frequently but I usually feed with starter wort with like 30 IBUs.

    I don't get a lot of early souring with my culture so it's probably fairly light on the lacto. Get lots of flavor development out of it though.
     
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  10. ncaudle

    ncaudle

    Joined:
    Apr 10, 2013
    Location:
    Virginia
    this. I've been recently propping up vials of mixed cultures I saved off and put in my fridge (some were 3-4+ years ago) without feeding them since banking. it takes a few days (maybe 3-4 tops) before visible/active signs of life but they all prop back up just fine, like I just banked them a month or 2 prior. no excessive acetic acid or other off flavors/aromas
     
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