Yeast cell counts - Home Brew Forums
Home Brew Forums > Home Brewing Beer > Fermentation & Yeast > Yeast cell counts
Cool Brewing Giveaway - Supporting Membership Drive & Discount

Reply
 
Thread Tools
Old 08-13-2010, 07:32 PM   #1
jmf143
Recipes 
 
May 2010
Wixom, Michigan
Posts: 608
Liked 21 Times on 19 Posts



Jamil had this on mrmalty.com:

Pitching a Wyeast Activator pack gives the following results within 12 to 18 hours:

1 liter starter = about 150 billion cells
2 liter starter = about 200 billion cells
1 liter starter, then pitched into 4 liter starter = 400 billion cells

Anyone know what the numbers would be for a Wyeast Propagator?


__________________
Vir sapit qui pauca loquitur

 
Reply With Quote
Old 08-13-2010, 10:35 PM   #2
pompeiisneaks
Why that human mask?
HBT_LIFETIMESUPPORTER.png
 
pompeiisneaks's Avatar
Recipes 
 
Jan 2009
Redmond, WA
Posts: 853
Liked 52 Times on 29 Posts


From wyeast's site faq:

6. Do I need to make a starter for an Activator?

No. The Activator is designed to deliver professional pitch rates (6 million cells/ ml.) when directly added to 5 gallons of wort. ( <1.060 at 70 degrees). However, if a package is slow to swell, suspected of being mishandled, or if the date is approaching the six month shelf life it is a good idea to build the culture up with a starter. High gravity or low temperature fermentations require higher pitch rates. This can be achieved with inoculating with additional packages or making a starter.

Edit: I should have done the math just in case, the packs have this listed on them:

The Activator™ has a minimum of 100 billion cells of pure, ready-to-pitch yeast, plus an internal nutrient packet. The Activator™ is designed to inoculate five gallons of wort (up to 1.060 SG) providing the pitching rate recommended by professional brewers.


__________________
~Phil
Fermenting/Kegged/Bottled NONE :( I moved to the NW and haven't had time to setup my brew rig since! (but hey, I'm in the Pacific NW so there's so much awesome beer I don't need to brew it as much hah!

 
Reply With Quote
Old 08-13-2010, 11:07 PM   #3
indigi
Recipes 
 
Jul 2010
Philadelphia
Posts: 438
Liked 2 Times on 2 Posts


That doesn't answer his question at all. The Propagator packs have way less cells - I think 1/3 - than an Activator. I don't know enough about yeast reproduction to say exactly what you'll need to do to get from 33 billion cells up to wherever you're going, but I don't think 18 hours is enough time to do it in.

 
Reply With Quote
Old 08-13-2010, 11:10 PM   #4
pompeiisneaks
Why that human mask?
HBT_LIFETIMESUPPORTER.png
 
pompeiisneaks's Avatar
Recipes 
 
Jan 2009
Redmond, WA
Posts: 853
Liked 52 Times on 29 Posts


Sorry bad headache today... totally misread... from wyeast's site on the PROPAGATOR.
The Propagator™ package contains a minimum of 25 billion cells in a yeast slurry. This volume is not adequate for direct pitching into 5 gallons of wort and requires a 1-2 L propagation step prior to brewing

both of which took me 3 seconds on wyeast's site...
__________________
~Phil
Fermenting/Kegged/Bottled NONE :( I moved to the NW and haven't had time to setup my brew rig since! (but hey, I'm in the Pacific NW so there's so much awesome beer I don't need to brew it as much hah!

 
Reply With Quote
Old 08-13-2010, 11:31 PM   #5
indigi
Recipes 
 
Jul 2010
Philadelphia
Posts: 438
Liked 2 Times on 2 Posts


Very true. I imagine he was looking for more pointed information, but didn't give us anything else to go on.

 
Reply With Quote
Old 08-14-2010, 02:49 AM   #6
jmf143
Recipes 
 
May 2010
Wixom, Michigan
Posts: 608
Liked 21 Times on 19 Posts


Sorry about the confusion - thought the questions were clear. What would a Propagator grow to if pitched into a 1 liter starter? A 2 liter starter? A 1 liter starter that was then re-pitched ("Stepped up") into a 4 liter starter?
__________________
Vir sapit qui pauca loquitur

 
Reply With Quote
Old 08-14-2010, 10:30 AM   #7
sigurdur
Recipes 
 
Sep 2009
Iceland
Posts: 41
Liked 2 Times on 2 Posts


Set the viability to 25% in the PRC (don't calculate by date) to see how big a starter you need.
If you want answers to how much you will get if you have 1 liter or 2 liter starters, you need to play with the numbers in the calculator (usually enough just to play with OG)



 
Reply With Quote
Reply
Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
Yeast Starters, not just for increasing cell counts anymore DirtyPolock Fermentation & Yeast 5 08-04-2010 10:16 PM
Increasing Cell Counts in Starters permo Fermentation & Yeast 16 06-18-2010 06:06 PM
Yeast Starter - For cell growth or to wake them up? yournotpeter Fermentation & Yeast 3 05-15-2010 02:36 AM
How do you know the cell count of your washed yeast? petep1980 Fermentation & Yeast 8 11-22-2009 03:28 PM
My Back is Sore or I've Been Doing Cell Counts for Too Long NotALamer Fermentation & Yeast 4 08-10-2009 12:05 AM


Forum Jump