Old mixed culture

[wmcc75]

Hello,
I recently found a very old slury of mélange in my fridge. It's really old, like left over from last year. I made a 3/4 or so gallon starter and it's happily fermenting after about a 20 hour lag, much shorter than I expected for such an old slury. I was wondering if the cultures are going to be way off from it being so old and having sat in the back of my fridge for so long? Like out of wack off?

 

[ShareBrewing]

Watch the episode of Brewing TV about sour beers. The great Michael Dawson showed an entire family tree of the various sour beers that have been connected through re-pitching or re-using old mixed culture trubs/cakes. He talked about 1 or 2 cakes that sat dormant in carboys hidden away in his office for several years. He reused 1 cake that was around 5 years old. That too fired up within 24 hours and quickly finished a complex fermentation within a week!

Perhaps an even older cake could result in a faster souring/fermentation? Anyone have experience on this? I plan on re-using an old mixed culture cake fairly soon.

 

[secondbase]

I've used mixed culture slurry that was ~8 months old. The resulting beer is 4 months old and very sour despite using 10ibu. I think the outcome it will depend on what you've got in there.

 

[ShareBrewing]

Very true, obviously over time the various bacteria/yeast populations will change. The bacteria would most likely be the fastest reproducing organism, compared to the yeast. This could explain why some old slurries will sour/ferment a beer at such an accelerated pace.

 

[505-Brewer]

Bacteria and brett. Might want to add some sacc otherwise if the starter tastes good you're all set.