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General Category => Yeast and Fermentation => Topic started by: trev on October 11, 2011, 03:03:09 AM

Title: Yeast starter in fridge
Post by: trev on October 11, 2011, 03:03:09 AM
Hello all,
Long story short.  Created a 1L yeast starter with Munich lager yeast last Tuesday the 4th.  Put the starter into the fridge on Friday night, preparing to brew on Saturday.   Wife went into labor on Friday night thus preventing brewing.  My question is, how long will this starter last in the fridge.  It's still on the erlnmyer flask with an airlock.

Thanks,

Trevor
Title: Re: Yeast starter in fridge
Post by: James Lorden on October 11, 2011, 03:18:13 AM
Congradulations,

It won't last six months which is probably the next time you'll have time to brew ;D

Realistically it will last awhile but will become less powerful as the yeast lose viability.  Honestly 1 liter is sort of small for most 5 gallon lager batches.  What you can do is decant and make another starter when you get a chance to reschedule.  This way you'll be stepping up the starter to get even more yeast for your lager
Title: Re: Yeast starter in fridge
Post by: tschmidlin on October 11, 2011, 03:24:03 AM
I agree with what's above, but when you get a chance, decant the liquid and top it up with distilled water.  Even better if it's been boiled/chilled, but a brand new bottle will be sterile enough.  The water will help the yeast last longer than the acidic/alcoholic environment they are sitting in now.
Title: Re: Yeast starter in fridge
Post by: euge on October 11, 2011, 04:17:12 AM
^^^^ All that. Oh it might be awhile with the newborn. Congratulations. /raise.

Concentrate on that and the SWMBO will be appreciative. If it's just a few weeks then warm and feed the yeast the night before brewing or make a starter. You could pitch right out of the fridge but prepping the yeast is easy and makes for better beer.

Good luck! Boy or girl?
Title: Re: Yeast starter in fridge
Post by: trev on October 11, 2011, 04:22:19 AM
Hi guys, thanks for the tips.  Yes the starter is small,  I started out making. 2L but the flask cracked when I put it in the ice bath.  I do have an extra pack of the Munich though.
Title: Re: Yeast starter in fridge
Post by: trev on October 11, 2011, 04:23:55 AM
Baby boy, Zane.
Title: Re: Yeast starter in fridge
Post by: tschmidlin on October 11, 2011, 04:42:09 AM
Baby boy, Zane.
Nice, congratulations :)
Title: Re: Yeast starter in fridge
Post by: James Lorden on October 11, 2011, 03:05:55 PM
I agree with what's above, but when you get a chance, decant the liquid and top it up with distilled water.  Even better if it's been boiled/chilled, but a brand new bottle will be sterile enough.  The water will help the yeast last longer than the acidic/alcoholic environment they are sitting in now.

Any fear that distilled water will leach minerals out of the yeast?
Title: Re: Yeast starter in fridge
Post by: davidgzach on October 11, 2011, 03:21:11 PM
Baby boy, Zane.

Congrats! 

If you plan to brew in the next week or so I would leave it as is in the fridge, buy a new 2L flask or even better a 5L, decant and make a new starter before brew day.

If it's going to be longer, I agree with above. 
Title: Re: Yeast starter in fridge
Post by: denny on October 11, 2011, 03:41:24 PM
I agree with what's above, but when you get a chance, decant the liquid and top it up with distilled water.  Even better if it's been boiled/chilled, but a brand new bottle will be sterile enough.  The water will help the yeast last longer than the acidic/alcoholic environment they are sitting in now.

Any fear that distilled water will leach minerals out of the yeast?

I've heard people who have been to Siebel say that they were taught there that distilled water is the preferred medium for yeast storage.  Apparently its complete lack of nutrients makes the yeast go dormant for storage.  What says Dr. Tom?
Title: Re: Yeast starter in fridge
Post by: a10t2 on October 11, 2011, 03:46:37 PM
It's still on the erlnmyer flask with an airlock.

Just checking - you didn't use the airlock while it was fermenting, right?
Title: Re: Yeast starter in fridge
Post by: tschmidlin on October 11, 2011, 04:00:28 PM
I agree with what's above, but when you get a chance, decant the liquid and top it up with distilled water.  Even better if it's been boiled/chilled, but a brand new bottle will be sterile enough.  The water will help the yeast last longer than the acidic/alcoholic environment they are sitting in now.

Any fear that distilled water will leach minerals out of the yeast?

I've heard people who have been to Siebel say that they were taught there that distilled water is the preferred medium for yeast storage.  Apparently its complete lack of nutrients makes the yeast go dormant for storage.  What says Dr. Tom?
I'm not sure of the exact mechanism, but distilled seems to be better than tap water.  I can think of a few reasons why it might work, but I haven't read or done any research on it and it would be pure speculation.

As for distilled leeching minerals out, if the yeast cells can't hold on to their contents against a gradient, you probably don't want to ferment with them.  Just my opinion.
Title: Re: Yeast starter in fridge
Post by: trev on October 11, 2011, 06:55:27 PM
It's still on the erlnmyer flask with an airlock.

Just checking - you didn't use the airlock while it was fermenting, right?

Yes, no stir plate.  Should I have not used an airlock?

One more question.  Those flask are pyrex, correct?  I know you can safely boil in them but is it alright to go directly to an ice bath?

Thanks again guys, appreciate the congrats and the advice!
Title: Re: Yeast starter in fridge
Post by: morticaixavier on October 11, 2011, 07:05:19 PM
It's still on the erlnmyer flask with an airlock.

Just checking - you didn't use the airlock while it was fermenting, right?

Yes, no stir plate.  Should I have not used an airlock?

One more question.  Those flask are pyrex, correct?  I know you can safely boil in them but is it alright to go directly to an ice bath?

Thanks again guys, appreciate the congrats and the advice!

They are pyrex and you should be able to go directly from hot to cold with it but it sounds like that didn't work so well for you last time. It was probably a flaw in the glass in that case which means you should be thankful that it happened in the icebath rather than the stove top.

The idea behind not using an airlock is that in the growth phase the yeast want all the O2 they can get so by usng a piece of foil you can maximize the yeast's access to air. I also do not use a stirplate but I swirl the flask whenever I notice it.
Title: Re: Yeast starter in fridge
Post by: James Lorden on October 11, 2011, 07:19:02 PM
When putting the flask in the ice bath you don't want the cold water to go higher then the liquid in the flask.  That can cause a problem.
Title: Re: Yeast starter in fridge
Post by: trev on October 11, 2011, 09:48:13 PM
When putting the flask in the ice bath you don't want the cold water to go higher then the liquid in the flask.  That can cause a problem.
Yup that is exactly what I did too!  Covered about 2-3" above the liquid line.

It's still on the erlnmyer flask with an airlock.

Just checking - you didn't use the airlock while it was fermenting, right?

Yes, no stir plate.  Should I have not used an airlock?

One more question.  Those flask are pyrex, correct?  I know you can safely boil in them but is it alright to go directly to an ice bath?

Thanks again guys, appreciate the congrats and the advice!

I will try foil next time.  Looks like I might be making another starter with this one in the fridge before I brew.

Thanks!