the_new_darren
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I heard Chris White say that the yeast straight from a pack/vial is usually healthier and more viable than the average HBers 500ml starter
tnd
tnd
Yeast Starter And Splitting Yeast Packs
- Thread starter Tony
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pyrosx
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A commertcial yeast manufacturer encouraging people to buy new packs rather than farm them up themselves?
I'm shocked.
iralosavic
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So if you need 400 billion cells for a lager and you start with a 30ml sample (25billion cells), but let's assume 50% viability and go with 12.5 billion viable cells, what would the ideal starter stepping process be?
According to yeastcalc, the bigger the initial starter the higher final count after each step, but you want to avoid underpitching in starters too, so what is the ideal plan of attack here?
Multipliers of 4 for lagers have been mentioned, (although I'm not sure what the principal behind that is), so using this I would go
1. 100ml
2. 400ml
3. 1600ml
I now have 236 billion cells, according to yeastcalc, so I would need to add a fourth step involving a further 3L wort to get approximately 400b cells. Is this the safest, most efficient process or could a step be cut back somewhere?
Cheers
EDIT: Probably should have based the calculations of the viable yeast of 12.5b cells:
1. 50ml
2. 200ml
3. 800ml
4. 3200ml - still only ~ 300b cells - at this step, even a 5L starter would only achieve 367 (according to the calculator)
5. God knows - this is getting a bit silly.
So yeah, someone please help me!
According to yeastcalc, the bigger the initial starter the higher final count after each step, but you want to avoid underpitching in starters too, so what is the ideal plan of attack here?
Multipliers of 4 for lagers have been mentioned, (although I'm not sure what the principal behind that is), so using this I would go
1. 100ml
2. 400ml
3. 1600ml
I now have 236 billion cells, according to yeastcalc, so I would need to add a fourth step involving a further 3L wort to get approximately 400b cells. Is this the safest, most efficient process or could a step be cut back somewhere?
Cheers
EDIT: Probably should have based the calculations of the viable yeast of 12.5b cells:
1. 50ml
2. 200ml
3. 800ml
4. 3200ml - still only ~ 300b cells - at this step, even a 5L starter would only achieve 367 (according to the calculator)
5. God knows - this is getting a bit silly.
So yeah, someone please help me!
Where is the article from the initial post on this new website?
http://www.aussiehom...showarticle=192
The link is broken as it seems are all the other links from AHB articles.
http://www.aussiehom...showarticle=192
The link is broken as it seems are all the other links from AHB articles.
MartinOC
Insert something suitably witty here
I second that emotion!
Adr_0
Gear Bod
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Awesome article and thread.
I have a quick - i.e. long, convoluted, repetitive, semi-distracted and eventually to the point - question:
If you have a marginal Wyeast/Whitelabs pack, e.g. beteween 1-20% viability, is there any advantage to splitting this pack into three vials VS throwing the whole lot into a starter and the splitting the resulting slurry?
Some more analysis just for what I'm getting at:
Scenario 1 (split Wyeast pack into three):
100bn cells, 40% viability = 60bn dead cells. Each vial will have 20bn dead cells, 13bn live/viable cells. One of these is stepped through starters for a growth factor of ~20, so maybe 260bn live cells going into the primary.
Brewing a month apart with these you might get further reduction in viability (20%, 10%), taking a guess at your pre-fermernation total cells maybe 150bn and then 70bn cells for the third vial. Don't take the numbers too literally, but you see where I'm going here.
Scenario 2 (full Wyeast pack, split primary slurry):
100bn cells, 40% viability = 40bn live cells, stepped through same starters ~20x = 800bn cells going into Primary, another factor of 2-3 which hopefully puts it around 1500-2500bn (let's say 1500bn with 50-60% viability). Splitting this three ways gives 500bn decent cells per whack. Even loss of viability over 1-3mths (5-10% viability, 25-50bn) should get you needing just a small starter to wake everything up by the time you get to through it.
BUT... what are typical viability numbers after the yeasties have gone through a primary fermentation? A 1:10 or 1:20 step is a lot bigger than a normal 1:2 or 1:4 step, so is the viability right down?
I have a quick - i.e. long, convoluted, repetitive, semi-distracted and eventually to the point - question:
If you have a marginal Wyeast/Whitelabs pack, e.g. beteween 1-20% viability, is there any advantage to splitting this pack into three vials VS throwing the whole lot into a starter and the splitting the resulting slurry?
Some more analysis just for what I'm getting at:
Scenario 1 (split Wyeast pack into three):
100bn cells, 40% viability = 60bn dead cells. Each vial will have 20bn dead cells, 13bn live/viable cells. One of these is stepped through starters for a growth factor of ~20, so maybe 260bn live cells going into the primary.
Brewing a month apart with these you might get further reduction in viability (20%, 10%), taking a guess at your pre-fermernation total cells maybe 150bn and then 70bn cells for the third vial. Don't take the numbers too literally, but you see where I'm going here.
Scenario 2 (full Wyeast pack, split primary slurry):
100bn cells, 40% viability = 40bn live cells, stepped through same starters ~20x = 800bn cells going into Primary, another factor of 2-3 which hopefully puts it around 1500-2500bn (let's say 1500bn with 50-60% viability). Splitting this three ways gives 500bn decent cells per whack. Even loss of viability over 1-3mths (5-10% viability, 25-50bn) should get you needing just a small starter to wake everything up by the time you get to through it.
BUT... what are typical viability numbers after the yeasties have gone through a primary fermentation? A 1:10 or 1:20 step is a lot bigger than a normal 1:2 or 1:4 step, so is the viability right down?
Yob
Hop to it
So Ive recently done this with 2 different Vials of Yeast, WLP001 and WLP099
After pitching there remains a tiny little bit of yeast in the vial, Ive added maybe 5-10ml of starter wort to the vial and done the old shake when pass, after a few days of this I then top up the vial and let go for another couple of days,
(pictured WLP099)
this then goes right into a 500ml starter and then onto a 2l starter, which I spin for 48 hours and then let ferment out and settle. I can either then use or split and freeze as desired. The one pictured below is destined fro Freezing.
(Pictured WLP001)
The one above was pitched from the 500ml to the 2l last night
:icon_cheers:
After pitching there remains a tiny little bit of yeast in the vial, Ive added maybe 5-10ml of starter wort to the vial and done the old shake when pass, after a few days of this I then top up the vial and let go for another couple of days,
(pictured WLP099)
this then goes right into a 500ml starter and then onto a 2l starter, which I spin for 48 hours and then let ferment out and settle. I can either then use or split and freeze as desired. The one pictured below is destined fro Freezing.
(Pictured WLP001)
The one above was pitched from the 500ml to the 2l last night
:icon_cheers:
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