Pitching washed yeast? - Home Brew Forums

 Home Brew Forums > Pitching washed yeast?

02-16-2010, 02:01 AM   #1
palongee1
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Feb 2010
idaho
Posts: 7

newbie here. Ive been learning lots from the members on this board Been brewing all grain with a buddy for the last year or so and would like to start reusing the yeast. We currently make our starters based on Mr malty's pitch rate calculator. What im trying to figure out is when reusing the yeast to make a starter how do you have any idea what the cell count your pitching is gonna be? Generally, using the calculator we pitch 1 smack pack with say 1000ml of wort. I know they say there are X amount of cells in the smack pack and what the recomended pitch rate should be for a specific gravity of wort, but how can you figure out how many cells are in the salvaged yeast? Ive done alot of reading regarding overpitching and underpitching effects to the beer, using the smack pack you get an idea of what you got to work with. Is there a way to measure or get a idea of where youre at or is everyone just winging it?..thanks in advance for your input! Mike

02-16-2010, 02:31 AM   #2
thunder
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Dec 2009
Texas
Posts: 202

I have used this method for washing yeast.Not sure of the cell count but it is probadly
equal to 2-3 smack packs .Have never had any issues.
http://www.homebrewtalk.com/f163/yea...strated-41768/

02-16-2010, 02:46 AM   #3
robertvrabel
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Jan 2010
Farmington Hills, MI
Posts: 242
Liked 9 Times on 4 Posts

Quote:
 Originally Posted by thunder I have used this method for washing yeast.Not sure of the cell count but it is probadly equal to 2-3 smack packs .Have never had any issues. http://www.homebrewtalk.com/f163/yea...strated-41768/
One of those jars illustrated in that thread, is equal to 2-3 smack packs?? If so that is crazy... that 1 pitch turns into 8-12 packs.

02-16-2010, 03:26 AM   #4
palongee1
Recipes

Feb 2010
idaho
Posts: 7

Thanks for the replies, so if each one of those jars is equal to 2-3 smack packs are you guys pitching the entire jar to your fermenter or the entire jar to a starter or a partial jar.... According to Ole Mr malty, 3 smack packs is what would be ideal for for my 10.78 ipa or 1 pack with a 1.6 liter starter on the stir plate. So im curious what people are doing to ensure they are pitching at least close to the right amount of yeast..not too much, not too little? Maybe im overthinking this..ive been known to do that.....thanks again!
Mike

02-16-2010, 04:56 AM   #5
bigjoe

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Feb 2009
Blue Springs, MO
Posts: 258
Liked 3 Times on 3 Posts

you need to know how much yeast is in your jar after you wash it. If you let it sit in the fridge for a while it gets quite compacted. Take another jar that is exactly the same and add water until it reaches the same level as the yeast jar. Then measure that quantity of water to know how many ml's you have. Adjust the date on mr. malty for your slurry. Listening to jamil on a podcast he recommends to leave the concentration and viability setting at thier defaults. Piece of cake. I think those numbers on mr. malty are for straight yeast with no starter. If you were to make a starter on some really old yeast I think you'd still be good.

02-16-2010, 05:43 AM   #6
palongee1
Recipes

Feb 2010
idaho
Posts: 7

Thanks for the reply. I saw the slurry section on mr malty, SO... it can be measured by volume, bitchen. I will give this a try. So basicly if it says to pitch 150ml of thick slurry there is no need to use a starter since all of the needed cells should be present? It has been interesting using starters how quickly the fermentation starts and how fast it hits final gravity compared to just pitching a single smack pack in most the beers weve done..lovin it

02-16-2010, 10:17 PM   #7
bigjoe

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Feb 2009
Blue Springs, MO
Posts: 258
Liked 3 Times on 3 Posts

Quote:
 pitch 150ml of thick slurry there is no need to use a starter since all of the needed cells should be present?
Yes and no. The starter not only increases cell count, but it also "proofs" the yeast. If you familiar with baking, making bread in partcular, its common to throw the yeast into water with some sugar to proof it. It lets you know the yeast is viable. The same idea applies to a starter for beer. Your proofing the yeast as well as increase cell count.

Having said all that I've used 3 week old yeast off a batch that I washed. Didn't use a starter and didn't have any problems. If it was a recent harvest of yeast and you had a healthy fermentation, and clean beer from it you can probably just pitch at the rates on Mr Malty, but at some point the amount of yeast you need to pitch is stupid. Play with the dates on the calculator. I think I set it to 2 months old and it said I needed close to 1000ml of yeast.

Yes pitch rates make a huge difference in the beer with out a doubt.

Reason: Pitch rates

02-16-2010, 10:23 PM   #8
permo
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Sep 2009
North Dakota
Posts: 2,952
Liked 55 Times on 48 Posts

If you wash yeast, then you certainly have the know and skill to make a simple starter. This makes sure you have viable yeast and also vastly increases the cell counts. With washed yeast, especially older than a few weeks, a starter is a great idea. I make a starter for all of my washed yeast and I have had great success. I capture fairly small washed samples, but lots of them. I just make starters and step them up as necassary. I find that I would rather have many small samples of yeast to use over time than use up my entire strain pitching big slurries without starters.