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General Category => Yeast and Fermentation => Topic started by: HydraulicSammich on July 16, 2011, 05:11:45 AM

Title: Am I over-pitching?
Post by: HydraulicSammich on July 16, 2011, 05:11:45 AM
I am making a starter of London ESB for a Porter of 1.055.  I only had a two liter Erlenmeyer for the stir plate.  I had a smack pack produced in May.  Mr. Malty suggested a two liter starter.  I also had a smack pack of ESB made in Jan.  Mr. Malty wanted to use 4 or 5 liters for one pack.  I used both smack packs in a 1.7 liter starter.  There is a lot of yeast being produced.  So, will the yeast be viable as in growth phase and will it be to much to pitch in a 5 gallon batch?  
Title: Re: Am I over-pitching?
Post by: Jimmy K on July 16, 2011, 05:48:53 AM
Over pitching really requires a lot of yeast and a 1.7 let starter isn't really that big. So without doing any calculations I'd say your fine.
Title: Re: Am I over-pitching?
Post by: nateo on July 16, 2011, 03:51:17 PM
MrMalty is more of a guesser than a calculator. It's a good guesser that I use all the time with good results, but it's really just a guess. Without actually counting your yeast and testing viability, you have no idea how much yeast you're actually pitching.

The good news is it's basically impossible to overpitch, on a homebrew scale, unless you really try to overpitch. I'm talking like 5 smack packs, and even then it'd probably still make good beer.
Title: Re: Am I over-pitching?
Post by: denny on July 16, 2011, 04:35:14 PM
I'm wondering if a 1.7 L starter will be big enough for 2 smack packs.  IIRC, there's needs to be enough "food" for they yeast to rebuild it's glycogen reserves at the end of fermentation.  In 1.7L there may not be enough.  I don't know for certain, just thinking "out loud".
Title: Re: Am I over-pitching?
Post by: a10t2 on July 16, 2011, 05:47:28 PM
I'm wondering if a 1.7 L starter will be big enough for 2 smack packs.

They're pretty old packs though. Something like 70 billion cells total between them. So unless you're using a stir plate and/or aeration, you may be under-pitching.
Title: Re: Am I over-pitching?
Post by: HydraulicSammich on July 16, 2011, 08:33:05 PM
Denny, I was wondering the same thing about reserves.  I did add nutrient to the starter but it is highly floculating in two days.  I don't know if that means it ran out of steam early.  I suppose it is pitch and learn.
Title: Re: Am I over-pitching?
Post by: tom on July 16, 2011, 08:35:07 PM
1 pack in 1 L on a stirplate will double the yeast.