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General Category => Yeast and Fermentation => Topic started by: James Lorden on July 05, 2011, 08:20:40 PM

Title: How much yeast can be harvested from a 5 gallon carboy?
Post by: James Lorden on July 05, 2011, 08:20:40 PM
standard gravity beer, approximately how many ounces (or ml) should be harvested? I feel like I am coming up short.
Title: Re: How much yeast can be harvested from a 5 gallon carboy?
Post by: bluesman on July 05, 2011, 08:26:06 PM
It depends on the strain of yeast, health of the starter yeast, amount of residual trub and amount of flocculation. Assuming you had a healty and appropriate pitch of yeast, one can estimate the yeast to bud 2-3 times. It then becomes a calculation usung your starting volume of yeast slurry.
Title: Re: How much yeast can be harvested from a 5 gallon carboy?
Post by: a10t2 on July 05, 2011, 08:30:55 PM
Assuming you had a healty and appropriate pitch of yeast

And plenty of oxygen. That might be the biggest variable for home brewers.
Title: Re: How much yeast can be harvested from a 5 gallon carboy?
Post by: bluesman on July 05, 2011, 08:35:47 PM
Assuming you had a healty and appropriate pitch of yeast

And plenty of oxygen. That might be the biggest variable for home brewers.

Agreed.
Title: Re: How much yeast can be harvested from a 5 gallon carboy?
Post by: James Lorden on July 05, 2011, 08:49:31 PM
Ok so ballpark, using english ale ( wlp 002 ) well aerated with o2, and pitched per mr. Malty pitching calculator - just looking for a ballpark, ( on the move and hoping for an estimate here ) I rushed and only got 4 ounces - 002 flocks like a ton of bricks and I think I didn't break all the clumps up initially.
Title: Re: How much yeast can be harvested from a 5 gallon carboy?
Post by: blatz on July 05, 2011, 08:53:30 PM
Ok so ballpark, using english ale ( wlp 002 ) well aerated with o2, and pitched per mr. Malty pitching calculator - just looking for a ballpark, ( on the move and hoping for an estimate here ) I rushed and only got 4 ounces - 002 flocks like a ton of bricks and I think I didn't break all the clumps up initially.

yeah - you didn't swirl enough (which is a prereq with that strain especially). that said, 4oz will probably be enough to repitch an average gravity 5gal ale.

I generally get anywhere from 1.5-2.5 quarts or so of slurry for 12gal.  YMMV.
Title: Re: How much yeast can be harvested from a 5 gallon carboy?
Post by: bluesman on July 05, 2011, 08:56:02 PM
Ok so ballpark, using english ale ( wlp 002 ) well aerated with o2, and pitched per mr. Malty pitching calculator - just looking for a ballpark, ( on the move and hoping for an estimate here ) I rushed and only got 4 ounces - 002 flocks like a ton of bricks and I think I didn't break all the clumps up initially.

According to mrmalty. a 1.050 gravity beer will need approx. 175 million cells which would render an 86 mL slurry. So you would end up with 86 mL x 4 = 344mL. This equates to approx 12 oz of slurry.

Also keep in mind the thickness of the slurry will have a significant impact on the volume. In other words more beer in the slurry will increase the volume of the slurry and so on.
Title: Re: How much yeast can be harvested from a 5 gallon carboy?
Post by: The Professor on July 05, 2011, 11:08:21 PM
Typically when I've used 002 (and most other ale yeasts) I get enough slurry to potentially pitch three batches,   so I usually wind up using only about 1/3 of it  (or 1/2 of it,  if its next fermenting a stronger beer or if the slurry has been in the fridge for more than a couple weeks).
Title: Re: How much yeast can be harvested from a 5 gallon carboy?
Post by: James Lorden on July 06, 2011, 07:41:51 PM
Thanks guys, I was in a bit of a bind yesterday.  Generally when I repitch I am not really paying attention to how much yeast I get I just always have enough and the extra gets tossed.  Yesterday I was brewing 10 gallons of a high gravity beer and collected yeast from a 5 gallon carboy... I had split my previous batch so the second carboy had a completely different yeast.  When I looked at my numbers I'd run from  the night before I realized that I didn't have enough yeast  :o.  I had never repitched 002 before and thinking back the trup I dumped did look extra clumpy - that english yeast flocs like peanut butter so I just didn't shake it enough.

Anyway all is well.  Good for me I pressure can starter wort so I was able to throw a few liters onto a stir plate and make a quick starter - hopefully this will be catastrophe avoided....assuming I had as much yeast going into the starter as I calculated - I was moving fast since I was going away and had to pitch by a certain time that evening.  Fingers crossed.
Title: Re: How much yeast can be harvested from a 5 gallon carboy?
Post by: bluesman on July 06, 2011, 08:51:02 PM
Thanks guys, I was in a bit of a bind yesterday.  Generally when I repitch I am not really paying attention to how much yeast I get I just always have enough and the extra gets tossed.  Yesterday I was brewing 10 gallons of a high gravity beer and collected yeast from a 5 gallon carboy... I had split my previous batch so the second carboy had a completely different yeast.  When I looked at my numbers I'd run from  the night before I realized that I didn't have enough yeast  :o.  I had never repitched 002 before and thinking back the trup I dumped did look extra clumpy - that english yeast flocs like peanut butter so I just didn't shake it enough.

Anyway all is well.  Good for me I pressure can starter wort so I was able to throw a few liters onto a stir plate and make a quick starter - hopefully this will be catastrophe avoided....assuming I had as much yeast going into the starter as I calculated - I was moving fast since I was going away and had to pitch by a certain time that evening.  Fingers crossed.

Glad to hear it all worked out for you James.  :)

I always keep my fingers crossed in this great hobby of ours.