Yeast Culture Fermentation Q

[stef]

According to the helpful hints i got here a few days ago, i made a yeast culture from a few bottles of coopers sparkling ale.

Added 100grams ldme to 1l of boiling water and mixed them up, cooled it and divided it into 2 750m PET bottles. Added the sediment and dregs from the stubbies and placed the caps on the bottles (not screwed down- i dont have any more airlocks) and put them in a cupboard. Its probably only about 16ish degrees in cupboard though.

My question is how long and how vigorous should the fermentation be? After 10 hours the bottles looked the same, though with about 4mm of sediment on the bottom. After 24 hours there were little white specs on the surface (i assume the krausen) and after 36 hours the white specs have increased (looks like a few bits of foam about the size of a 5c peice floating on top) but there is still hardly any foam on the surface of the wort.

I assume the white is krausen, but there isnt much of it, and its taken 36 hours- i was under the impression fermentation is usually over pretty quickly in these smallish cultures. There is still a lot of stuff in suspension in the wort.

I was hoping to pitch these cultures into a brew i plan to do tomorrow night. Would that be ok? Or does it have to be at a certain stage before its viable? I was going to refrigerate over night tonight, then get rid of most of the liquid tomorrow morning, pour the sediment from 2 bottles into 1 and add a little fresh wort for 10 hours to get it going again, then pitch. Would that work? Or would refrigerating at this stage kill the yeast?

Cheers,

Stef

 

[Rodolphe01]

You don't get a great deal of activity from starters so don't be too concerned. Chilling it down won't harm the yeast so don't worry about that either. You can taste the 'beer' that you pour off the starter to get an idea if it is infected, however don't expect it to taste great even if it isn't infected. Use Mr Malty or something to make sure you have enough cells from your starter.

Also probably a good idea to close the caps on the bottles up tight and shake the crap out of the bottles, then *gently* re-open slightly so they can vent as before.

 

[MaltyHops]

I've done this a few times recently and the white specs are probably over columns of
bubbles (partying yeasties) and eventually these increase until full krausen. I'd put a
paper tray basket over an oil heater set to minimum heat (making sure the tray is well
supported) and put a starter over it so even at around 25C, it took a couple of days to
reach full krausen so you might want to do this if you're hoping to pitch in a few days'
time. Could just rubberband some glad wrap over the spout with pinprick hole.

T.

 

[stef]

I've put the bottles into a little box with a lid and i've got a warm wheat bag in there with it. Looks like its doing the trick- begining to foam up a little more.

 

[MaltyHops]

I think I've found an excellent bottle for storing yeast trub
and even part of making a starter. Don't know about you guys
not in SA but here we can get a fruit juice by Bickfords that
come in 250mL P.E.T. bottles - pretty solid, really clear as
- just the right size for collecting yeast (after separating
from the heavier trub deposits) as shown below. The juice is
not bad so if you got to get some, get these and save the
bottles for brewing use

Also shown is one of the bottles with about 50mL of 1040 wort
ready for the test tube of activated yeast from a slant, all of
which will go into the flask (when it's been going a while in the
juice bottle) to make the final starter.

T.

 

[Bubba]

According to the helpful hints i got here a few days ago, i made a yeast culture from a few bottles of coopers sparkling ale.

Added 100grams ldme to 1l of boiling water and mixed them up, cooled it and divided it into 2 750m PET bottles. Added the sediment and dregs from the stubbies and placed the caps on the bottles (not screwed down- i dont have any more airlocks) and put them in a cupboard. Its probably only about 16ish degrees in cupboard though.

My question is how long and how vigorous should the fermentation be? After 10 hours the bottles looked the same, though with about 4mm of sediment on the bottom. After 24 hours there were little white specs on the surface (i assume the krausen) and after 36 hours the white specs have increased (looks like a few bits of foam about the size of a 5c peice floating on top) but there is still hardly any foam on the surface of the wort.

I assume the white is krausen, but there isnt much of it, and its taken 36 hours- i was under the impression fermentation is usually over pretty quickly in these smallish cultures. There is still a lot of stuff in suspension in the wort.

I was hoping to pitch these cultures into a brew i plan to do tomorrow night. Would that be ok? Or does it have to be at a certain stage before its viable? I was going to refrigerate over night tonight, then get rid of most of the liquid tomorrow morning, pour the sediment from 2 bottles into 1 and add a little fresh wort for 10 hours to get it going again, then pitch. Would that work? Or would refrigerating at this stage kill the yeast?

Cheers,

Stef

You need to keep agitating your starter, every time you walk past it, give it a good swirl as often as you can. The serious guys use stirring plates to keep them constantly agitated.
I also stepped mine up after a few days (added more malt and water to make it bigger up to about 1-1.5litres). Keep it pretty warm, over 22.
It took me about 5 days to get a good krauzen, and lots of swirling and I pitched the lot but took the volume (1.5l) into acount with the final volume in the fermenter to make sure I ended up with only 23l.