Yeast Starter And Splitting Yeast Packs

[tiprya]

Ok - thanks heaps for the explanation Tony.

Reading through all of the info now about stepping up yeasts etc, I'll just have to account for the lower initial yeast count in my starter (from collecting the vials) and step it up more to get to the correct pitching rate.

 

[JoeF]

Awesome article Tony - Thank you!

I used this method the first time recently for a lager yeast (Wyeast 2287) and found I only had some slight krausen for a day or two, just small thin white foam and then it dissapated quite quickly. I've been intermitantly swirling and now the yeast has settled to a cake. Is this normal to have little or no krausen for a lager yeast? Should I pour out the wort and taste it and add some more to 'step it up' as the cake is still rather small and being a lager yeast I want to be sure I have enough to pitch into 23 litres?!

Thanks in advance

 

[stux]

Awesome article Tony - Thank you!

I used this method the first time recently for a lager yeast (Wyeast 2287) and found I only had some slight krausen for a day or two, just small thin white foam and then it dissapated quite quickly. I've been intermitantly swirling and now the yeast has settled to a cake. Is this normal to have little or no krausen for a lager yeast? Should I pour out the wort and taste it and add some more to 'step it up' as the cake is still rather small and being a lager yeast I want to be sure I have enough to pitch into 23 litres?!

Thanks in advance

Did you pitch into a starter volume?

You can use this website to calculate your starter steps

http://yeastcalc.com/

If you split a wyeast 4 ways, then use 25Billion as the initial cellcount, and the same production date. I normally do a double step starter for fresh yeast, and a triple step if its ancient

 

[cdbrown]

From the yeast website - for a pilsner with OG1.047 and volume 42L I need 735B cells. I figure I'll need 3 steps from 1 - 2.5 - 5L in order to get the required cell count from a split pack. Going straight to a 5L won't be enough. Great website as I would have probably underpitched thinking a straight 5L would be good enough on a stir plate.

Now for stepping do you step it each day or maybe every 2nd day?

 

[JoeF]

Did you pitch into a starter volume?

You can use this website to calculate your starter steps

http://yeastcalc.com/

If you split a wyeast 4 ways, then use 25Billion as the initial cellcount, and the same production date. I normally do a double step starter for fresh yeast, and a triple step if its ancient

Hey Stux

Thanks for the reply and the link

Yep, I pitched @ 24c into an Erlenmyer flask 1 litre of wort, made with 100gms of LDME boiled for 10mins, then stepped after 2 days with another 400mls of wort (I ran out of LDME!)

I now have more DME and am wondering if I should to a 1 or 1.5 litre step? Taste and discard the 'old' wort whilst leaving the yeast cake and add more wort?

I'm not 100% sure...

Also, in the link does the 'starter volume' in the 2nd and 3rd step refer to the total volume, as in 1.5ltr + 1.5 ltrs = 3 ltrs for the second step or just how much is added each step?

Thanks again

 

[cdbrown]

Hey Stux

Thanks for the reply and the link

Yep, I pitched @ 24c into an Erlenmyer flask 1 litre of wort, made with 100gms of LDME boiled for 10mins, then stepped after 2 days with another 400mls of wort (I ran out of LDME!)

I now have more DME and am wondering if I should to a 1 or 1.5 litre step? Taste and discard the 'old' wort whilst leaving the yeast cake and add more wort?

I'm not 100% sure...

Also, in the link does the 'starter volume' in the 2nd and 3rd step refer to the total volume, as in 1.5ltr + 1.5 ltrs = 3 ltrs for the second step or just how much is added each step?

Thanks again

I always thought it was just topping up the volume, but after looking at the Care and Feeding of Your Yeast link on that page, he says to chill, decant, allow to warm and add the next step volume.

Let your wort ferment at around 70 degrees for 24 hours.
Put the vessel in the refrigerator and let it chill for 12 24hrs. This will vary depending on the floccability of the yeast.
Carefully decant the spent wort from the yeast, leaving just enough wort to produce a thin slurry.
If one step was all you needed to reach your optimum pitching rate; let the slurry warm up to room temperature and pitch it into your wort.
If you need to step it up. Its time to make your second starter; its probably no surprise that the second starter is made in exactly the same way as the first starter. Once the second step has chilled, transfer the wort onto the yeast slurry in the first starter, once again using proper sanitation methods. Let this second volume of wort ferment as before, chill, decant, and pitch.

 

[cdbrown]

I've got an old irish ale (WY1084) from June 10 and london ale 3 (WY1318) from April 09 so they both have very very low viability. Would I be best off making a starter for these and trying to build the cells up to 100B or so before doing the split into containers? I forgot that I had them, but am planning on using this year hopefully.

 

[Pennywise]

Thanks for the link Stux, very helpful :icon_cheers:

 

[Steve@PMF82]

I've got an old irish ale (WY1084) from June 10 and london ale 3 (WY1318) from April 09 so they both have very very low viability. Would I be best off making a starter for these and trying to build the cells up to 100B or so before doing the split into containers? I forgot that I had them, but am planning on using this year hopefully.

Yeah i would, this is what i would do.
Not bother smacking them, use the nutrient sachet in your starter wort, then steps of 100ml, 500ml then 1 - 2L.
Let the last stage of starter ferment out and clear on its own at ferment temps, then decant spent wort and wash the yeast.
After that split it up into smaller container or vile for longer term storage in the fridge.

 

[cdbrown]

Ordered the 30ml containers but just got a call saying they were now all out of stock (labelled and unlabelled). Thankfully the 50ml containers are in stock and only a few $ more.

So are you suggesting to just top up the starter or follow the chill, decant, new wort, repeat. Ferment for a day 100ml, chill the next and decant, ferment for a day 500ml, chill the next and decant, ferment for a few days 2L which by that stage should have lots of fresh yeast, chill and decant and split.

 

[RobW]

Nice article Tony.

Can I suggest that you spray the aluminium foil that covers the flask with sanitiser too.

Also don't leave any cultures with the lid off for longet than is absolutely necessary and as suggested already give the caps of your vials a spray before you open them as well.

 

[Steve@PMF82]

Ordered the 30ml containers but just got a call saying they were now all out of stock (labelled and unlabelled). Thankfully the 50ml containers are in stock and only a few $ more.

So are you suggesting to just top up the starter or follow the chill, decant, new wort, repeat. Ferment for a day 100ml, chill the next and decant, ferment for a day 500ml, chill the next and decant, ferment for a few days 2L which by that stage should have lots of fresh yeast, chill and decant and split.

I give the 100ml a couple of days, then add to 500ml - i then let the 500ml ferment out and drop bright at ferment temps( 2 - 4 days depending on the yeast ) then decant spent wort and step up to 1 - 2L depending on how much yeast i want to grow, then let that ferment out and clear and only use the slurry. All my wort for farming is 1032 - 1035

Of course you can do the overnight chill to help drop the yeast out, this is how i started out doing it, but after doing some further reading on yeast, i prefer to let it all happen and ferment temps, i find i get a clearer spent wort rather than trying to force it through chilling. IMO the yeast will be healthier not going through the chill / warm cycle several times.

It takes some more planing, 7 - 10 days in advance of when you are going to brew, but i find its worth it for happy healthy yeast.

 

[craigev]

Anyone know, if splitting after making the 2L starter, will the resultant vials follow the same viability depreciation levels as shown in the yeast calc ? eg approx 50% after 2 months from making the starter ( assuming the original smack pack was 100% viable at the time of starting)

Or is this considered as slurry and depreciates even more than pure liquid yeast ?

 

[Steve@PMF82]

Anyone know, if splitting after making the 2L starter, will the resultant vials follow the same viability depreciation levels as shown in the yeast calc ? eg approx 50% after 2 months from making the starter ( assuming the original smack pack was 100% viable at the time of starting)

Or is this considered as slurry and depreciates even more than pure liquid yeast ?

Use the slurry calculator here http://www.mrmalty.com/calc/calc.html

 

[craigev]

Use the slurry calculator here http://www.mrmalty.com/calc/calc.html

Thanks, but unfortunately I think the "slurry" they are calculating for in that calc is for harvested yeast from normally fermented beer slurry. It predicts viability of only 10% after slurry is kept for about 7 weeks. This is undoubtedly true for beer slurry, but what about starter slurry ?

I have used starter slurry after 2 months and, although I always start the slurry again in 2L on a stir-plate, you would surely get a pretty poor fermentation starting with only 10% viable yeast !

anyone know about the deterioration of viabilty of slurry harvested from starter wort ? Maybe its mid way between liquid yeast and normal beer slurry ?

without having some clue its pretty pointless using a calculator.

 

[Steve@PMF82]

Thanks, but unfortunately I think the "slurry" they are calculating for in that calc is for harvested yeast from normally fermented beer slurry. It predicts viability of only 10% after slurry is kept for about 7 weeks. This is undoubtedly true for beer slurry, but what about starter slurry ?

I have used starter slurry after 2 months and, although I always start the slurry again in 2L on a stir-plate, you would surely get a pretty poor fermentation starting with only 10% viable yeast !

anyone know about the deterioration of viabilty of slurry harvested from starter wort ? Maybe its mid way between liquid yeast and normal beer slurry ?

without having some clue its pretty pointless using a calculator.

I farm my yeast and only pitch starter slurry, which i wash, measure and store for later use.
The viability of the yeast may be slightly better than that of a full batch of beer slurry, especially if that has not been washed.
All you have to do is play around with the slide bars on the calculator, ie: increase your estimated cell count / ml from the default setting 2.4b/ml.
Put the non yeast % down to 5% or zero if you like.
Its the most accurate your going to get unless you have a microscope. At least using that calculator gets you in the ballpark, gives you some idea about the quantity of yeast your pitching, and if you follow the same procedures again and again you can work out which settings work the best for your setup, which will lead to more consistent yeast handling and more consistent fermentation.

EDIT: this yeast calculator is also excellent - http://www.yeastcalc.com/
Also unless your re-pitching onto a whole yeast cake its pretty hard to over pitch with slurry and even if you did it would only be slightly over, which IMO is better than under pitching.

 

[cdbrown]

I smacked the 2 yo irish yeast and it took about 3 days to fully swell so happy with that. I did a 200ml starter mainly because 100ml in the 2L flask on the stirbar wasn't going to work with the slightly concave base. Anyway it's been on the stirplate for about 5 or so days at 20c. I meant to top it up with 500ml wort earlier in the week but just didn't have the time so hopefully will get to it tonight. It should be all ok to build after being so long on the stirplate? If I get it going tonight I'll leave for a few days before switching off to settle, decant and then add a bigger wort starter.

 

[Steve@PMF82]

I smacked the 2 yo irish yeast and it took about 3 days to fully swell so happy with that. I did a 200ml starter mainly because 100ml in the 2L flask on the stirbar wasn't going to work with the slightly concave base. Anyway it's been on the stirplate for about 5 or so days at 20c. I meant to top it up with 500ml wort earlier in the week but just didn't have the time so hopefully will get to it tonight. It should be all ok to build after being so long on the stirplate? If I get it going tonight I'll leave for a few days before switching off to settle, decant and then add a bigger wort starter.

I cant see it being a problem being on the stir plate for that long (happy to hear otherwise) except that it will be heavily oxidized which you should take into account with future taste tests.

When you top it up remember to take into account the dilution to your new wort, from the 200ml you already have in there.

 

[cdbrown]

When you top it up remember to take into account the dilution to your new wort, from the 200ml you already have in there.

I don't quite get what you mean - can you explain please? edit - I get it now - need to bring the wort up to 1.040ish not just add new wort at 1.040. So take into account the 200ml is at 1.012 (guess)

I was concerned about the oxidation - the starters always smell and taste fairly ordinary.

 

[raven19]

Dilution is certainly something to take into account for larger starters for sure. 4L lager starter into a 20L batch is significant dilution (unless you chill down after the starter has consumed all the sugars).

I must admit I don't allow for any dilution with my beers. I do note down everything as best I can so I can recreate cracking beers though.