How much yeast should I be harvesting?

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fluxcapacitor

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I recently got tired of paying $8 for a new vial of yeast for every batch so I've started harvesting yeast by scooping a bit of the krausen into pint jars with a large sanitized spoon. My first brew using harvested yeast came out well, but now I'm wondering how much yeast I should be collecting when I harvest. I drop few scoops of krausen into pint jars and then fill the jars with cooled boiled water. After water clears and the yeast flocculates, the volume of yeast I end up with varies anywhere from just a 1/8" thin layer up to a 1/2" layer at the bottom of the jar. I always make a starter before pitching to get my cell count up and get the yeast moving, but is there a general rule of thumb for the volume of yeast I should be harvesting to pitch into a starter for a future batch?
 
There is no recommended amount on how much you should or shouldnt harvest, but I wash the yeast after fermentation and then save the washed yeast in 2 oz bottles. I generally get about 1 oz of thick yeast, and the rest is water, in the containers. I find that this is plenty to make a starter with and ferment a new batch. Its about the same amount of yeast you would find in a vial or smackpack. Check out https://www.homebrewtalk.com/f163/yeast-washing-illustrated-41768/

If you want to save more, this may help. And its all up to you on how much you want to save. If its a strain I use a lot, I'll save more, vice versa if its a strain i dont use much
 
I've been mentally debating this as well - I figure as long as you make a starter with what you have, you'll be okay.

BUT sometimes if I have enough slurry, I'll just pitch it straight into the primary. I generally won't do this if the yeast is more than about 2 weeks since harvesting. Try to mark the side of your jars with mL so you can have a decent idea of quantity.

As for, "Do I have enough to make a starter," you're supposed to step up your yeast by no more than 10 times. Try to fit yourself into this scenario: you can harvest up from a bottle or two of Sierra Nevada with 50mL, then move to 500mL, then anywhere up to 5000mL. So if you think you have 5x as much yeast on the bottom of your jar than in a bottle conditioned beer, why not make maybe a 200mL starter, then step up to anything under 2000mL. The first step could just be for ~36 hours, enough to wake the yeastie boys up.

Pretty soon you'll be like me and saying, "Man I hate spending money on DME for starters. Maybe I could mash just a few pounds of grain and jar up 2gal of starter wort ready to go..."
 
Maybe I could mash just a few pounds of grain and jar up 2gal of starter wort ready to go..."

I brewed and bottled a batch of 1.040 wort once just for starters. Bottled in 22 oz bombers, which I don't use for beer.

They were all gushers. There is a long thread on this board about this, and the recommendation is to use proper canning technique, which is to boil in a pressure cooker to get to 250 degrees to ensure sterility. The normal boil isn't good enough to kill botulism spores. Well, that was the advice from guys who knew a lot more about this topic than I.
 
I think you might be harvesting the wrong stuff. If I understand you, you're skimming krauesen during fermentation; I recommend harvesting post-fermentation instead. You get much better slurry that way.

Harvesting and repitching skimmed yeast tends toward powdery - not very flocculant - yeast, especially with certain ale strains, after a few generations. If you harvest settled yeast, you tend to get a more homogenized sample.

If you're pitching soon after harvesting, you need neither wash nor "step up" the slurry. Slurry harvested without processing/washing loses approximately 25% viability per each seven days of cold storage. So if you're pitching the harvested slurry within a few days after harvesting, there's no real need to wash it or step it up with a starter; just pitch an amount of surry appropriate for your OG and style. Even if you pitch after, say, two weeks, you can get away without building a starter. Simply pitch 150% of the slurry your calculations indicate (the extra 50% takes into consideration the loss of two weeks' storage).

Good luck!

Bob
 
I think you might be harvesting the wrong stuff. If I understand you, you're skimming krauesen during fermentation; I recommend harvesting post-fermentation instead. You get much better slurry that way.

Really? According to John Palmer's chapter on yeast in HTB, "Each batch of beer you brew is a good source of yeast for a future batch. The best way to obtain yeast is to skim it from the krausen of a currently fermenting beer."

Anybody have experience harvesting with both methods? Notice any differences in the attenuation or flocculation?
 
I thought it depended on the strain. For instance, if you use a top cropping strain, the best way to get the slurry is from the second skim at about day three. Many open fermentation reccommended strains are top croppers. At least that's my understanding.
 
Really? According to John Palmer's chapter on yeast in HTB, "Each batch of beer you brew is a good source of yeast for a future batch. The best way to obtain yeast is to skim it from the krausen of a currently fermenting beer."

Anybody have experience harvesting with both methods? Notice any differences in the attenuation or flocculation?

Yes. I've got experience. That's why I wrote what I did! :D

You can top-crop. That's a very traditional, English way to harvest yeast from open fermentation. Edited to add: Many strains noted as suitable for open fermentation are indeed "top-croppers". That doesn't mean you must top-crop, or that you even should.

I recognize Palmer's prophet-like reputation. I still maintain it's better to harvest from the "lees" of a finished ferment. First, there's no chance of contamination through fannying about in an active ferment (though it's possible to worry too much about that). Second, as I wrote before, you get a more homogenized sample of cells by bottom-harvesting - you get cells that flocced early, late, and properly - which avoids promoting powdery characteristics in your culture.* Third, you get more yeast for the effort, making pitching the next generation less of a hassle - top-cropping seldom yields sufficient yeast to properly pitch the next batch.

I used Ringwood for years, both professionally and as an amateur, and if ever there's a top-cropper, it's Ringwood. I maintained better results with easier propagation by bottom-harvesting than top-cropping.

Your mileage may vary.

Regards,

Bob

* Powdery strains are the reason for technologies like the Burton Union system.
 
I think you might be harvesting the wrong stuff. If I understand you, you're skimming krauesen during fermentation; I recommend harvesting post-fermentation instead. You get much better slurry that way.

Harvesting and repitching skimmed yeast tends toward powdery - not very flocculant - yeast, especially with certain ale strains, after a few generations. If you harvest settled yeast, you tend to get a more homogenized sample.

If you're pitching soon after harvesting, you need neither wash nor "step up" the slurry. Slurry harvested without processing/washing loses approximately 25% viability per each seven days of cold storage. So if you're pitching the harvested slurry within a few days after harvesting, there's no real need to wash it or step it up with a starter; just pitch an amount of surry appropriate for your OG and style. Even if you pitch after, say, two weeks, you can get away without building a starter. Simply pitch 150% of the slurry your calculations indicate (the extra 50% takes into consideration the loss of two weeks' storage).

Good luck!

Bob

So if I am reading this correctly, I harvested yesterday (Sunday) and plan on pitching next Sunday (7 days later), so as long as I have ~1000mL of slurry, I should be good? Treat it like a vial and bring it to room temp ~68°F?

It was a WLP-001 in a light amber ale. 10 gallon batch. Any recommendation against this?

(Forgot to add--It will be pitched into a pale.)
 
So if I am reading this correctly, I harvested yesterday (Sunday) and plan on pitching next Sunday (7 days later), so as long as I have ~1000mL of slurry, I should be good? Treat it like a vial and bring it to room temp ~68°F?

It was a WLP-001 in a light amber ale. 10 gallon batch. Any recommendation against this?

(Forgot to add--It will be pitched into a pale.)

Well, you'll need to plug the OG of your recipe into the calculator to be sure how much you'll need, but yeah, I should think a liter is enough.

Pitch away!

Bob
 
First off, Bob, thank you for your response. I wish i could sit across from you and talk about all of the brewing-related questions that almost always fill my mind.

To report, I pitched the ~800mL of slurry into my pale Sunday at about 4PM. I know that realistically I should be able to just shake the begeeses out of the container of slurry and then pitch at pitching temp, but I put it on a stir plate for the short period while brewing to bring it to pitching temp.

I pitched into my 10 gallons of oxygenated (with this)
IMG_0127.jpg

wort, and less than 12 hours later my blowoff tube was bubbling in the bucket of sanitizer like mad!!!

So, thanks again for the info. Any recommendations for how may generations I should be able to do this to? I will be harvesting from this batch for my next batch.
 
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