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Taking yeast from a primary cake?

MaltLicker

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Rather than dumping all/most the primary cake into something and washing it, does anyone here just grab a tablespoon of yeast from the empty primary and use that yeast in a new starter? 

Anyone have a ballpark estimate of how many cells might be in a heaping, messy tablespoon?  Thx.
 
I read somewhere there is about 1 billion per ml of yeast/trub from the bottom of a bucket or carboy.    You never know how viable they will be at that stage though so you would want to assume about 75% or 750 million cells per ml. 

This is probably from a George Fix book or something Jamil mentioned on the Brewing Network.

 
I have racked rite n top of it a few times. as long as the new beer is close to the same style it has worked well for me.

Matt
 
I'm new to the yeast washing business. Often what I have done in the past is take a scoop of sludge and pitch it into the new batch. Half cup usually works. Yeah I know I'm adding trub and hops, which is why I started washing the yeast.
 
Often what I have done in the past is take a scoop of sludge and pitch it into the new batch. Half cup usually works. Yeah I know I'm adding trub and hops, which is why I started washing the yeast.

So..... I am ready to rack an IPA to secondary, but want to hang on to some of the yeast for another batch....but more of a cream ale..... will that work?
Sorry, not trying to hijack, trying to stay on topic.....I used an American Ale (Wyeast #1056)...... or how do I 'wash it' and save it for a brew in a week and a half without going thru all the tempermental hoo-ha needed for yeast cultivating and such?
 
I boil off 500ml of water in my 2 liter Erlenmeyer flask and cover it with foil immediately.  I let it cool to room temp which is the same room as my sludge left over from the last brew.    I sanitize my hands, the carboy, foil and everything around me (I keep starsan in a spray bottle with distilled water).  I swirl the sludge up  in the carboy then pour 500 ml into the flask and quickly cover with foil again.  I swirl this around a bit then let it settle in the refrigerator.

On brew day, I set the flask on the counter and let it come to room temp.  30 minutes before pitching, sanitize everyting again I decant off most of the water.  Sometimes I pitch the whole thing and sometimes I try to slowly pour the yeast in leaving as much trub behind as I can.  By then the homebrew I have had during the brew day makes my a bit shaky and I get a little sloppy trying to run a thin thread of yeast into the fermenter. 

I have had perfect luck with this method.  Sometimes I keep about 1liter of sludge if I am making a bigger beer.

 
So..... I am ready to rack an IPA to secondary, but want to hang on to some of the yeast for another batch....but more of a cream ale..... will that work?

I don't see why not.

Washing it isn't that hard. Here's what I do. Keep in mind that I'm not as anal about sanitation with this yeast washing business as I probably should be, but I haven't had any problems either.

After racking I'd add water to the carboy, a quart or so. In my case I'm on a drilled well so I don't need to do anything with the water.

After mixing it up well, walk away for a half hour or so. Most of the hops and trub will settle out, and the liquid will be the water you just added and yeast. Pour the liquid off into something that will hold it and put it into the fridge. At this point it's washed enough that it shouldn't add much unwanted material the next brew.  You could just pour off the water and pitch the settled yeast on brew day, or you could wash it more.

There are several instructive videos on the subject on youtube. https://www.youtube.com/watch?v=tGvw0JV0oKo for example.

Or you could wait to rack on brew day. Scoop out some unwashed sludge and set it aside, then pitch it instead of whatever yeast you would normally use. I've done that a score or more times (never more than five in a row) without any problems.
 
Pour the liquid off into something that will hold it and put it into the fridge. At this point it's washed enough that it shouldn't add much unwanted material the next brew.  You could just pour off the water and pitch the settled yeast on brew day, or you could wash it more.
Or you could wait to rack on brew day. Scoop out some unwashed sludge and set it aside, then pitch it instead of whatever yeast you would normally use. I've done that a score or more times (never more than five in a row) without any problems.

hmmm...so I've got a quart jar of sludge from my Bock about a month ago that I put in the fridge immediately after I racked..... Bohemian lager Wyeast #2124 so it's a bit darker than I want, but if I do an amber or something, would it still be ok?
Even though the IPA is ready to rack to secondary, maybe I'll just leave it and do it this weekend and do your method of 'washing'.....friggin all grain stuff is addictive!

I boil off 500ml of water in my 2 liter Erlenmeyer flask and cover it with foil immediately.  I let it cool to room temp which is the same room as my sludge left over from the last brew.    I sanitize my hands, the carboy, foil and everything around me (I keep starsan in a spray bottle with distilled water).  I swirl the sludge up  in the carboy then pour 500 ml into the flask and quickly cover with foil again.  I swirl this around a bit then let it settle in the refrigerator.

On brew day, I set the flask on the counter and let it come to room temp.  30 minutes before pitching, sanitize everyting again I decant off most of the water.  Sometimes I pitch the whole thing and sometimes I try to slowly pour the yeast in leaving as much trub behind as I can.  By then the homebrew I have had during the brew day makes my a bit shaky and I get a little sloppy trying to run a thin thread of yeast into the fermenter. 

I have had perfect luck with this method.  Sometimes I keep about 1liter of sludge if I am making a bigger beer.

So, it's kinda the same method, just a bit more rigorous.
Same question....about how long can I keep what I've got in the fridge?
 
How long can you keep anything in the fridge?

I taste everything that goes into my beer. Even the yeast. Even the sludge from the previous batch. Seriously.

Smell it. Taste it.  It should smell and taste like what it is. Trub (which is nothing but grain protein), hops, beer, and yeast.

If you get the sense that there's something growing in there that you didn't invite? Pitch it.

When in doubt, throw it out.
 
Maine Homebrewer said:
How long can you keep anything in the fridge?
I taste everything that goes into my beer. Even the yeast. Even the sludge from the previous batch. Seriously.
Smell it. Taste it.  It should smell and taste like what it is. Trub (which is nothing but grain protein), hops, beer, and yeast.
If you get the sense that there's something growing in there that you didn't invite? Pitch it.
When in doubt, throw it out.

Ok, fair enough!
 
I used yeast that was was 2 weeks old and it was fine.  I never used anything kept longer though I have kept it up to a month and it smelled OK.  I have also gotten food poisoning from eating old food out of the fridge that smelled OK.  YMMV
 
The yeast I got Tuesday from a local brewer looked a little chunky, so I washed it twice and then fed it almost a liter of starter Friday evening and put on stir plate. 

It was done in the morning, and I put it on the garage floor to cool it down.  It settled very well, so I decanted and pitched some very ready yeast around 4pm. 

 
Well back to the original question of the post... I was doing some reading over old notes and came across so relevant information. There is 14 ml of pure slurry in the bottom of a white labs vial and knowing that there are 100 billion cells in the vial (when fresh) doing the math leaves us with 7.1 billion cells per ml. A table spoon is 15 ml (14.786 ml to be exact) => so roughly 105 billion (104.98 billion to be more precise) cells per table spoon. I hope that's ball park enough.
 
I racked from primary last night and couldn't resist the thick layer of yeast and basically tipped it straight into a sterile jar, it all looks like yeast and theres loads of it. Going to try use it at the weekend which brings me to my question I normally would do a starter of 1.5lt but there seems to be loads in the jar should i maybe do a smaller starter, which begs another question is it possible to have to much yeast? Both brews are similar by the way.

 
Well, I have washed yeast maybe three times, but I'm glad I did this time.  I shed the chunks and each time poured off the less flocculent cells with the spent wort.  And then fed the best a small starter before game day. 

That's great fact-finding Curly.  Good to know.  If I can extract a heaping tablespoon, that's the same as a very fresh new package.  Start it up and brew again.
 
Curly55 said:
Well back to the original question of the post... I was doing some reading over old notes and came across so relevant information. There is 14 ml of pure slurry in the bottom of a white labs vial and knowing that there are 100 billion cells in the vial (when fresh) doing the math leaves us with 7.1 billion cells per ml. A table spoon is 15 ml (14.786 ml to be exact) => so roughly 105 billion (104.98 billion to be more precise) cells per table spoon. I hope that's ball park enough.

What? Can't get any closer than that? Tsk....disappointed am I.  ;)
So, using a pint of slurry might be a bit of overkill.....or over-feed as the case may be? Might have a bit of overflow in the blowoff tube....rut roh.... :eek:
Serously, as Scottie asked, is it possible to have too much?
 
Primary slurry is not as cell dense as a wl vial. Generally there is about10% trub and dead cells. Plus there is a little more water in the slurry.  Mr Malty . com will calculate the volume of slurry needed for a beer based on typica cell density.  125ml is typical for the usual 1.050 beer.

Slurry at the end of fermentation and clarification will not be perfectly healthy.  Sitting in the bottom of the fermenter for two weeks after fermentation has completed depletes much of their energy reserves.  Therefore, slurry will not keep for very long in the fridge. This is particularly true for situations that include dissolved oxygen. In the presence of oxygen the yeast will wake up and further deplete their reserves. As they deplete some cells will die. If I remember correctly slurry degrades at about 25% per week.  So, after two weeks you are adding 1/3 dead yeast. After 3 weeks it's about 1/2.

Slurry is best reused within days to a week. The fresher the better. After two weeks you should definitely make a small starter on brewday.  In fact, this practice is always beneficial, especially if you add some nutrients and oxygen to the starter. You will have much more healthy yeast, and they will be in the active stages of fermentation when you pitch. The exception to this approach is for delicate flavored beers (pilsner, kolsch, etc).  For these beers it's better to do the starter the day before, and then crash & decant overnight. 
 
tom_hampton said:
In the presence of oxygen the yeast will wake up and further deplete their reserves.

To avoid this depletion of yeast reserves, is this why some of our colleagues add some drops of olive oil to the starter?

R, Slurk
 
after bottling my beer. I just pour the yeast cake into another sanitized bottle, and have had no problems
 
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