Culturing Bottle Dregs Follow Up

Two weeks ago I talked about culturing up some souring microbes from a bottle of Petrus’ Oud Bruin.  In that post I added a little bit of starter wort to the bottle sediment to see if I could get a culture going.  The plan was to give it 4-5 warm days in the bottle then step up to a 500mL culture in a larger flask.

Well…. I didn’t quite get around to it as soon as I should have and it seems to have failed.
I looked at it around day 5 and saw a distinct increase in the volume of the sediment in the base of the bottle.  Something had indeed begun to grow.  The wort also seemed to be a little ‘ropey’ suggesting an even more dynamic culture that I would have thought so soon.  I didn’t really get back to the culture until a full two weeks after “pitching”.

Now as you can see in the video, there is a good head of mold on the top of it and that ropiness is connected to it.  I suspect maybe even at day 5 those ropes were the start of mold.

Now I am left to wonder:

  1. Did the culture not take off at all.  Was the sediment just not viable?
  2. Did my starter wort (1.030 OG) not provide enough nutrients to get the microbes off the ground fast enough?  Hopefully a good culture would have lowered the pH to the point where the mold wasn’t going to grow.
  3. Did I contaminate the wort myself at the outset and the project failed because of that?
  4. What to do differently next time with a different sour cultured beer?

I am still thinking it over, and I won’t be deterred.
Do you have any advice for me on this one?
Leave us a comment and tell me what I did wrong!