how much saved yeast cake do you pitch or should you pitch ?

[odie]

Those of you that are saving and re-using your yeast slurry. How much by VOLUME do you pitch?

I've been harvesting and reusing yeast for a couple years now...but it's just a guess as to how much to use each time.

How much yeast cake do y'all use? Actual volume of settled yeast cake. Pint? Quart? half pint? quarter pint? cup? 1/2 cup? etc.

I'm looking for measurable volume of yeast slurry, NOT "1/2 a cake" since "cake" is not a measure of volume.

I've been keeping slurry in 1/2 pint jars, but each slurry settles to only 1/4 to 1/2 the jar capacity and the rest is beer on top. So I guess I'm pitching 1/8 to 1/4 pint of settled yeast cake or quarter to half a cup of slurry.

 

[CascadesBrewer]

I'm looking for measurable volume of yeast slurry, NOT "1/2 a cake" since "cake" is not a measure of volume.

I think this is the best way for you to determine for your process. I transfer a lot of trub into my fermenter, so my volume would not apply to you. I believe you filter out trub, so your cake is likely a much higher percentage of yeast than mine. I find that a full pint jar filled with slurry is about 1/4 to 1/5 of my normal yeast cake, so that is the amount I would use if I am direct pitching fairly freshly harvested yeast into a new batch.

For reference, the left is some yeast that I harvested from a recent English Porter. The right is some yeast that I harvested from an overbuilt starter. I suspect they both have a similar amount of yeast.

 

[odie]

yes, I filter/screen all my wort before fermentation.

My jars of yeast cake look like the picture on the right. very white. after sitting awhile in the fridge they look like that.

I do note that the yeast cakes in the bottom of my old buckets and carboys was notably smaller after I started screening between kettle and fermenter. And notably whiter and cleaner looking too.

Would say 1/4 cup of clean yeast cake be a good solid pitch? That is 1/4 cup of well settled & compacted clean yeast cake? Not 1/4 cup freshly stirred up slurry which is half beer or more.

 

[day_trippr]

My typical pitch of well-compacted and decanted starter yeast is 200ml per 5 gallon half-batch (I do 10 gallon batches in carboys) of 1.070 wort and calculates to ~350B cells "at birth". It takes at least 3 days of chilling in the fridge to get that level of compaction, and it is "starter clean", so pretty much pure yeast.

I suspect it would take a full pint of "thick slurry" and maybe more to get close to that...

Cheers!

 

[Airborneguy]

I usually make starters but this week I did not have the time so I pitched a 1/2 pint of US-05 directly. I don’t filter trub, but I do use a hop screen so my harvests are usually very clean. The beer took off in a few hours and looked like it was going to blow out until this morning when it finally slowed.

 

[odie]

My typical pitch of well-compacted and decanted starter yeast is 200ml per 5 gallon

what? I gotta do metric conversion now??? fine...lol

so you are pitching almost a cup of yeast? The thick white glob at the bottom of the jar.

Guess I've been under pitching for a while I estimate my pitches of compacted yeast cake to be a quarter to half a cup.

Often I pitch wort into a recently finished keg so no telling how much yeast cake it in there. When the keg finishes, I eject whatever is left into mason jars to save for later and what does not get ejected is what i will pitch wort on.

 

[day_trippr]

Closer to 3/4 cup. I do pitch on the high side for ales - most recommend .75M cells/ml/°Plato while I use 1M cells - and I have no patience for slow or stalled fermentations so I add a plus factor on top of that. But to the point of using slurry, I've found it takes a long time for it to settle enough in the fridge to reveal something approaching its true volume so I will definitely err on the high side of how much to use...

Cheers!

 

[garibaldi83]

I usually make starters but this week I did not have the time so I pitched a 1/2 pint of US-05 directly. I don’t filter trub, but I do use a hop screen so my harvests are usually very clean. The beer took off in a few hours and looked like it was going to blow out until this morning when it finally slowed.

How old was the yeast? I plan on doing the same but it may be 2 to 3 weeks old by the time I get to it

 

[Airborneguy]

How old was the yeast? I plan on doing the same but it may be 2 to 3 weeks old by the time I get to it

I harvested the yeast on 2/20 and brewed with it on 3/7.

 

[garibaldi83]

This is my notty yeast, it's in a quart jar, harvested 4 days ago. When you say you pitched 1/2 pint was it including the beer or only the yeast?

 

[Airborneguy]

The one on the right is from the same batch of US-05, but the jar I pitched this week looked like the S-23 on the left. I poured off the 1/2” or so of beer before pitching.

 

[garibaldi83]

Right on, I wonder since your fermentation was so rigorous if you could have gotten away with half the amount

 

[Airborneguy]

Right on, I wonder since your fermentation was so rigorous if you could have gotten away with half the amount

Most likely. It’s a pale ale so I’m not too worried about a little extra yeast character. And US-05 is clean anyway. But since I have another jar already and will likely harvest more from this batch, I didn’t see any need to halve it.

 

[Dog House Brew]

I generally pitch a little less than a pint if using slurry. I fill the jar and what settles down is what I pitch. Most of my yeast is overbuilt starters. I‘ve thought of trying shaken starters and not worrying to much about measuring.

 

[bwible]

I don’t even go to all that. I plan batches with the same yeast in order from weak to strong, light to dark and I just brew the same day I rack and put the next beer right in the same fermenter on the same yeast cake. Depending on the yeast I might do 2-7 beers with the same yeast. I just did a mild ale and then a barleywine on some 1028. Thats all I wanted out of that yeast. 1056 is the one I always end up doing 6 or 7 out of because it makes so many things.

Then after that I buy another pack of yeast.

 

[odie]

here are some of my samples. These have been sitting in the fridge for several weeks or even a few months. They are well packed/settled so it no longer "slurry" but tight yeast cake. When I pitch these, I will fully decant the old beer and add some fresh wort so that I can swirl it up and get all the packed yeast loose enough to pour into the fermenter. What you see is very tight packed cake, a lot will stay stuck in the jar unless I swirl fresh wort to get it to break lose.

these are 1/2 pint jars and typically they pack down to 1/3 - 1/2 volume yeast cake. A half pint is one cup so I guess I'm pitching 1/3 to 1/2 cup of tight yeast cake, not lose slurry.

I'm assuming if you are pitching "slurry" then it has less yeast per same volume than a tight yeast cake will have

. My jars of "slurry" seem to pack down to half cake and half beer.

 

[garibaldi83]

Have you thought of using a sterilized spoon and just scoop some yeast out?

 

[odie]

Have you thought of using a sterilized spoon and just scoop some yeast out?

I use an entire jar in a 5 gal batch.

From what I've been reading on other posts...I'm kinda thinking that one jars is a single pitch so there would be no reason to scoop out less than the whole thing.

I guess I could keep larger jars and then just scoop half out.

 

[Dland]

The space between the dump valve and the rack valve on my fermentor holds about 1 quart. I leave all this in, but have dumped the solids before I rack the previous batch, so it is pretty much yeasty beer.

 

[hottpeper13]

I found this out after i got my bright field microscope. Brewdads calculator has a second step for starters that you can have not on a stir plate. So i make a 1.5L starter on a stir plate for my first gen. Then put 20L for the second step off stir plate.
Look at the cell counts for each, I divide the 1.5 starter cells into the 20L and then pitch that amount.
I think the volume left in the fermenter can be divided up that way.

 

[tuxkilla]

I didnt want to start a new thread for what might be a dumb question, but I saved some slurry from a previous marzen I made about 3 weeks ago and filled up 2 mason jars with slurry and some excess beer on top. The slurry separated out nicely in the fridge, but now that I have it pulled out the fridge and its warming up to pitch, the slurry has already started fermenting again. Is this normal? I cant decant off the beer since now I have krausen again on top. I cant tell if this is a good thing or a bad thing.

 

[hottpeper13]

Yup, I decant right away,or it starts making bubbles.

 

[Ninoid]

I add about one and a half cups of Ale yeast slurry (cake + beer) never older than one week to 5 gallons. This is probably an overpitch, but it turned out to be the best and safest way for me. I take the jar out of the fridge a few hours before, shake it well and pour it into the wort. In past years I used an older slurry and a few batches of beer went bad so now I don't keep it for more than a week and I don't use more than five generations of yeast.

 

[odie]

I didnt want to start a new thread for what might be a dumb question, but I saved some slurry from a previous marzen I made about 3 weeks ago and filled up 2 mason jars with slurry and some excess beer on top. The slurry separated out nicely in the fridge, but now that I have it pulled out the fridge and its warming up to pitch, the slurry has already started fermenting again. Is this normal? I cant decant off the beer since now I have krausen again on top. I cant tell if this is a good thing or a bad thing.

if it started fermenting again then I would say you racked tghe last batch before it was done.

 

[odie]

the amount I usually pitch is about 1/2 cup of highly compacted yeast cake...yeast cake, not trub and yeast since I filter my wort.

I save the yeast cake slurry in 1/2 pint jars, which after it compacts down, leaves me with half yeast and half beer on top.