Stepping up yeast starters

[Chris Craig]

There have been a few discussions lately at meetings about stepping up starters.

This is an excellent video that talks about the table on pg 143 of Jamil's Yeast book.

http://billybrew.com/stepping-up-a-yeast-starter

[Al-Loves-Wine]

This is some great info Chris! I've always been kind of curious on washed yeast, and how big your starter should be. I believe I've heard you say sometimes a washed yeast can be too much? I've just been getting into the habit of doing a starter for all liquid cultures now. I am getting ready to brew an ESB and have a jar of 1968 washed, and was going to put it on a 1.5L starter. Too much you think?

I'm still trying to get my head wrapped around washed cultures, and have read this a couple times hoping to get a better understanding. I guess the variables on washed cell counts are going to vary to a certain degree, but in my limited experience I've had decent luck with what I've washed.

http://www.wyeastlab.com/com-yeast-harvest.cfm

[feldmann]

I started washing yeast recently and I use the calculator at MrMalty, theres a tab for re-pitching from slurry.

http://www.mrmalty.com/calc/calc.html

[Chris Craig]

I started washing yeast recently and I use the calculator at MrMalty, theres a tab for re-pitching from slurry.

http://www.mrmalty.com/calc/calc.html

This is some great info Chris! I've always been kind of curious on washed yeast, and how big your starter should be. I believe I've heard you say sometimes a washed yeast can be too much? I've just been getting into the habit of doing a starter for all liquid cultures now. I am getting ready to brew an ESB and have a jar of 1968 washed, and was going to put it on a 1.5L starter. Too much you think?

I'm still trying to get my head wrapped around washed cultures, and have read this a couple times hoping to get a better understanding. I guess the variables on washed cell counts are going to vary to a certain degree, but in my limited experience I've had decent luck with what I've washed.

http://www.wyeastlab.com/com-yeast-harvest.cfm

It's hard to say if it's too much Al.  The problem is that you don't know how much yeast you have to start with, how healthy it is, etc.

[feldmann]

I also found this thread really useful: http://www.homebrewtalk.com/f163/how-do-i-know-how-much-yeast-slurry-use-417291/

You can estimate the volume of yeast you have in a jar by putting same amount of liquid in another like jar and then measuring it.
Depending on how effectively you have rinsed the yeast it is likely you will have around 2 - 3 bn cells per ml of compacted yeast in the jar.

So for example if you washed the yeast very well and had 50ml of yeast then you could estimate you have around 50 x 3bn = 150bn cells.
If you were less careful and the sample shows some discoloration from trub then go for a lesser density of around 2bn per ml (50ml x 2bn = 100bn cells)

Now how many of those cells are viable depends on age since fermentation was completed. When you input the harvest date for the yeast into Yeastcalc it will estimate how many viable cells you have and guide you to making a starter if required.

[Al-Loves-Wine]

This 1968 I'm using was washed by Reid, then a jar given to Pierre, and he gave a jar to me after he washed it and that was back around the Pics competition. And it doesn't wash real clean like most yeast. 1187 is another that comes to mind that I haven't had great luck washing, also could have been the trub from the stout, not sure.

I'm going to step it up by 500ml again tomorrow to increase its chances. That post from HBT is interesting, if thats the case, washed yeast has a high cell count. That's what I've really wondered, what the average cell count actually is if you collected 3 jars from one cake.

[jamie_savoie]

I've read that for each month you store the yeast, you lose about 20% viability.

I save my slurry in a 1L mason jar (I don't wash my yeast) and use mrmalty "Repitching from Slurry" tool and slide the yeast concentration to 4.5, enter the date I saved the yeast and it gives you how much ml of slurry you need (I add 10-20% more just to be sure).

If the yeast was in the fridge for longer than 3 months I make a 1L starter with about 200ml of slurry, when it's high krausen and the yeast is in suspend, I decant the flask to another flask leaving the dead cells/trubs behind.  Then I step it up to the count I need

Top cropping is another option but I never tried it

Also harvesting from starters is a good option that I do often

[Jake]

A little off topic, but how do the big breweries do it? I know that Pics top crops their yeast (which is not all that common, but makes sense if you're using open fermenters), but assuming you have an enclosed connical fermenter, and you're about to keg a batch of beer, can you just take the yeast you've used and re-pitch that without using a starter? I guess this would be similar to putting a new batch of beer on a yeast cake, but from what I understand, doing this is typically too many yeast cells than what is considered ideal, but is still doable.

I'm just wondering, if I have a connical and I can get good yeast cells, how much of the fresh slurry (without a starter) is considered ideal? I find starters are a pain and am considering buying a couple connicals; I would love the idea of being able to just take yeast from one after 7 days from the dump valve, and pitch that the following weekend on the new batch. Is it possible to do it this way without starters? Do big breweries do starters, or do they just re-pitch? .... educate me!

[DandyMason]

I've read that for each month you store the yeast, you lose about 20% viability.

I save my slurry in a 1L mason jar (I don't wash my yeast) and use mrmalty "Repitching from Slurry" tool and slide the yeast concentration to 4.5, enter the date I saved the yeast and it gives you how much ml of slurry you need (I add 10-20% more just to be sure).

If the yeast was in the fridge for longer than 3 months I make a 1L starter with about 200ml of slurry, when it's high krausen and the yeast is in suspend, I decant the flask to another flask leaving the dead cells/trubs behind.  Then I step it up to the count I need

Top cropping is another option but I never tried it

Also harvesting from starters is a good option that I do often

Good to know Jamie, I usually throw out harvested yeast if I dont use it within a couple weeks... I will reconsider that now and just pitch more, like you said

[Al-Loves-Wine]

Well for the record, the ESB I just brewed with the washed jar of 1968 that was 7ish months old. I started off at 1L on the stir plate, and added 500ml every 12 hours to get to 2L for a 36 hour period, and there was a healthy krausen this morning when I checked it. So stepping up definitely does work. I actually figured that yeast was going to be no good at all.

[jeffsmith]

A little off topic, but how do the big breweries do it? I know that Pics top crops their yeast (which is not all that common, but makes sense if you're using open fermenters), but assuming you have an enclosed connical fermenter, and you're about to keg a batch of beer, can you just take the yeast you've used and re-pitch that without using a starter? I guess this would be similar to putting a new batch of beer on a yeast cake, but from what I understand, doing this is typically too many yeast cells than what is considered ideal, but is still doable.

I'm just wondering, if I have a connical and I can get good yeast cells, how much of the fresh slurry (without a starter) is considered ideal? I find starters are a pain and am considering buying a couple connicals; I would love the idea of being able to just take yeast from one after 7 days from the dump valve, and pitch that the following weekend on the new batch. Is it possible to do it this way without starters? Do big breweries do starters, or do they just re-pitch? .... educate me!

Most big breweries will wash yeast with acid to remove impurities.