Storing mixed cultures?

[brownni5]

I've done a couple mixed fermentations now, and plan to keep doing them. Since I don't live near a HBS, I get everything online, and I'd also like to develop my own culture. The problem is, I can't brew as often as I'd like to, and I don't always want to brew sour/funky stuff. So, what's the best way to store those cultures in between brews?

I've had a couple growlers going with airlocks, feeding periodically with wort, then stick them in the fridge. Then I read that Brett doesn't do well refrigerated (which I can't really wrap my mind around), so I pulled them out and left in my basement. One of the cultures got this thick raft of grainy white stuff, looks like cheap parmesan cheese. 1. What is that? And b. What should I do different? That one might have gotten oxygen - the airlock got too dry.

Soon I hope to have a barrel from which I plan to keep a solera going, limiting my worry about keeping a culture going, but that then limits the sours I can have in rotation.

Thanks for all suggestions.

 

[RPh_Guy]

I use mason jars at room temp.

Make starter wort 1.030-1.040 with nutrient and a little bit of hops (1-3 g/L). Aerate.
Add the chilled wort to the sanitized jar and then add some of your culture.
Loosely cover so CO2 can escape. You could probably tighten the cap at some point but I leave mine loose so there's no risk of explosion.
Leave at room temperature.

Feeding time:
Every 3-6 months stir or shake the culture to suspend all the microbes. Pour out about 80-90% of it and then replace with fresh starter wort.

Pitching time:
Draw out some of the sediment with a sanitized tool (dropper pipette baster syringe etc) and add to your batch.

It's normal for a pellicle to form; that's nothing to worry about. Try not to disturb it between feedings.

 

[brownni5]

So the grainy pellicle is nothing to get excited about?

 

[RPh_Guy]

I think they're exciting because what's underneath is usually tasty.

http://www.milkthefunk.com/wiki/Pellicle

https://www.homebrewtalk.com/forum/threads/pellicle-photo-collection.174033/

 

[brownni5]

I got no problems with pellicles, usually (I found one on my jar of harvested 3724 the other day - whoops), but the thick grainy stuff actually looks pretty gross. I'll ignore and keep on keepin' on.

 

[RPh_Guy]

Care to post a clear photo?
It's only a problem if it's mold.

 

[brownni5]

Probably not going to get a good photo through a dark growler, but it's absolutely not mold.

Thanks for the replies.

 

[brownni5]

Ok, I just fed my cultures and this one smells like a dumpster. I'll give it a couple days - hopefully it isn't gone. I don't mind buying yeast/sour culture once...

 

[RPh_Guy]

A good dumpster or a bad dumpster?

 

[brownni5]

Not the best dumpster. I think I'll give it a couple days. This is the one that had the parmesan cheese looking pellicle.

 

[mashpaddled]

I've maintained mixed cultures in mason jars in the fridge for years. While it is true that brett does not store as well at fridge temperatures as it does at room temperature I have not had problems reviving mixed cultures (both sour and brett/sacc) from the fridge. Just feed periodically and make a starter before pitching. Alternatively I think you are fine to keep those containers at room temperature although they will consume sugar more quickly and require more frequent feedings.