Yeast Harvesting: A Novel Approach?

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I began washing and harvesting my own yeast about a year ago. I got excited and harvested 4 jars from 4 batches in the first month, leaving me with 16 jars of 4 different yeasts. Since I usually brew twice per month, I had a ton of yeast just sitting in my fridge. After using some of this stored (aka old) yeast in beers that came out less than perfect, I began tossing it - hours of work, down the drain. Then I had an idea - why can't I just harvest clean yeast directly from my starter? After trying out a few techniques, here's the process that seems most efficient:

Step 1: Make a starter (3 days prior to brewing) that is .5 liter larger than you need for your beer. Since the majority of 5 gallon batches require no more than a 1 liter starter, a standard 2000 mL flask or even gallon growler will work great. In the photo below, I needed a 2 L starter for a 10 gallon batch, so I made 2.5 L.

Yeast Harvesting: A Novel Approach? - Brulosopher - 1-232.jpg

Step 2: A couple days after making your starter, sanitize a 500 mL (1 pint) mason jar using the sanitizer of your choice. I prefer Iodophor.

Yeast Harvesting: A Novel Approach? - Brulosopher - 2-233.jpg

Step 3: Fill the sanitized mason jar directly from the starter - if you use a stir plate everything will be in suspension, otherwise shake it up a bit prior to pouring.

Yeast Harvesting: A Novel Approach? - Brulosopher - 3-234.jpg

As you can see, I poured about 500 mL of wort/slurry from my starter into the mason jar. After just a few minutes, you can already see the creamy white and very clean yeast settling to the bottom of the jar.

Yeast Harvesting: A Novel Approach? - Brulosopher - 4-235.jpg

Step 4: Place the capped jar in the fridge over night to crash the yeast.

If you plan to use the yeast within a week or so, you can decant the "beer" and pitch directly from this jar. However, if you like to use different yeasts and won't be returning to your freshly harvested yeast for awhile, you will want to store it in a more hospitable environment. Steps 5 and 6 address how to do this.

Step 5: Fill a 250 mL (1/2 pint) mason jar halfway with tap water then microwave it (without the lid!) for 2 minutes to sterilize and de-oxygenate the water.

Yeast Harvesting: A Novel Approach? - Brulosopher - 5-236.jpg

Remove the very hot jar and put the lid on (using pot holders... it's HOT!), then shake it up to sanitize the lid with the boiling water. Let this sit over night to chill to room temp. I usually do this right after harvesting my yeast from the starter.

Step 6: The next day, decant about 80% of the beer off of the pre-harvested yeast in the larger mason jar, making sure to agitate to release the yeast from the bottom of the jar. Then simply pour the yeast directly into the previously boiled water in the smaller mason jar.

Yeast Harvesting: A Novel Approach? - Brulosopher - 6-237.jpg

Cap tightly and place in the fridge. Within a couple days you will have very clear water on top of a clean and compact yeast cake. When you want to use this yeast, make a starter as usual, decanting most of the water off the yeast, leaving just enough to help break up the cake.

Some of the benefits I see to this method include:
  1. The yeast is un-hopped and as clean as it's ever going to be. In fact, this is basically how White Labs and Wyeast grow their yeast.
  2. Since you're only making one jar of yeast, you won't have to store a ton of yeast (some people won't like this point).
  3. You don't have to go through the "washing" process, which is a pain in the arse if you ask me.
  4. You can brew any beer you want, even a barley wine or RIS, and still harvest yeast, as you're getting the yeast prior to it fermenting the beer you will ultimately brew. I guess you will need a pretty large flask, though.
I hope this helps. I've used the same strain multiple times very successfully. I'll never go back to washing yeast again.

Yeast Harvesting: A Novel Approach? - Brulosopher - image-1-311.jpegYeast Harvesting: A Novel Approach? - Brulosopher - image-310.jpeg

Cheers!

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115 COMMENTS
Posted: 
November 1, 2012  •  04:07 PM
So, do you then repeat the process from what was then in the fridge to store more yeast for later?
 
Posted: 
November 1, 2012  •  04:15 PM
Thank you Brulosopher for taking some of your valuable time to post that interesting tutorial.
I might have missed the most important point: For how long can you store that yeast cake ( under water ) in the fridge : weeks?,
months? years ?
Best regards

Jacques
 
Posted: 
November 1, 2012  •  04:18 PM
That is a good idea, and similar to mine. I have started to make 5 starters from one vial if Whitelabs. Personally, I think it works great. All my beers have taken off really well with this method. I brew two 12 gal batches at a
time, therefore 4 carboys. Using this method, I have one left over to make more starters with.
 
Posted: 
November 1, 2012  •  04:20 PM
Everything makes sense, except I don't get the point of transferring to the smaller jar. Why not just leave it in the first jar and decant the beer off the top, then pitch the yeast directly into a starter?
 
Posted: 
November 1, 2012  •  04:38 PM
Not following the logic here. You say that you see the yeast settle to the bottom, but everything I've read says that TRUB is the primary sediment that settles to the bottom initially.

All other guides call for decanting the
liquid above the trub into another jar, this liquid being full of yeast. Then, after chilling, the yeast settles out. Am I missing something? Yeast should take a decent amount of time to come out of solution at room temperature.
 
Posted: 
November 1, 2012  •  05:12 PM
@Pash91 Absolutely!
 
Posted: 
November 1, 2012  •  05:14 PM
@eimar I'd stick with 4-6 months, though with a large enough starter I'm sure up to a year would work fine.
 
Posted: 
November 1, 2012  •  05:18 PM
@BigB You can absolutely do that, I just prefer to leave my yeast under a bed of deoxygenated and sterile water if I don't plan on using it for a couple weeks. It's just a safety precaution... and it only takes a few minutes.
 
Posted: 
November 1, 2012  •  05:23 PM
@nickmv A couple things... first, when you're washing used yeast, trub will most certainly settle to the bottom first, and rather quickly, hence the reason you'd let it settle for a few minutes then decant the beer off the top and
proceed. However, with this method you are harvesting yeast from a purely malt (unhopped) starter that has a stir bar keeping everything in suspension. Given the fact the volume is so small, it's unlikely there is too much protein
or lipids like you get in a 5+ gallon fermentation.

Second, the yeast I used in the demo was WLP002 English Ale, which is known for flocculating and dropping out quickly. This is mainly why you see the layer at the bottom. When
I've done this with less flocculant strains (e.g., WLP001), it takes a few hours for the cake to form.

Cheers!
 
Posted: 
November 1, 2012  •  06:15 PM
I think your metric to English volume calculations are off.
500 ml is roughly a pint (not 1/2 pint). Also, 250 ml is roughly 1/2 pint (not 1/4 pint).

Other than that this looks interesting. I used to wash yeast
post-fermentation but stopped when I went to 10 gallon batches using a stainless keg. I may now start harvesting from my starters.

I just tossed a few washed samples that were 2 to 3 years old. They still looked and smelled
o.k. but I didn't test for viability.
 
Posted: 
November 1, 2012  •  07:08 PM
@nickmv A couple things... first, when you're washing used yeast, trub will most certainly settle to the bottom first, and rather quickly, hence the reason you'd let it settle for a few minutes then decant the beer off the top and
proceed. However, with this method you are harvesting yeast from a purely malt (unhopped) starter that has a stir bar keeping everything in suspension. Given the fact the volume is so small, it's unlikely there is too much protein
or lipids like you get in a 5+ gallon fermentation.

Second, the yeast I used in the demo was WLP002 English Ale, which is known for flocculating and dropping out quickly. This is mainly why you see the layer at the bottom. When
I've done this with less flocculant strains (e.g., WLP001), it takes a few hours for the cake to form.

Cheers!
 
Posted: 
November 6, 2012  •  04:09 PM
Thanks for the information, I think I'll try it.
 
Posted: 
November 6, 2012  •  08:53 PM
@BDun You're absolutely right about my conversion mistake... woops! Corrected!
 
Posted: 
November 7, 2012  •  10:24 AM
This looks like a great method. I will be trying. I think washing is a pain in the arse too.
 
Posted: 
November 8, 2012  •  07:25 AM
@RmikeVT Right on, man. I've been using this method for the past few months and it has been working fantastically. I've got a couple strains that are on their 4th and 5th generations, and they still get going like crazy, making
great beer. Good luck! If you have any questions, don't hesitate to ask.
 
Posted: 
November 8, 2012  •  02:02 PM
I've been doing the same thing with either yeast recovered from bottles of bottle conditioned beer or from a vial of White Labs yeast. But I take it one step further. I freeze the yeast for long term preservation. I just wrote
an article on the process of freezing the yeast that was posted in the article section that is based on the approaches discussed in the thread on freezing yeast. Take a look.
 
Posted: 
November 9, 2012  •  05:37 PM
Bravo. All I can say is, "why didn't I think of this?"

Seriously though, thank you very much! Can't wait to get going on it.
 
Posted: 
November 11, 2012  •  03:08 PM
Thanks so much for sharing! I like the idea of using "clean" yeast as well as time saved.
I will be using this process!
 
Posted: 
November 13, 2012  •  03:27 PM
Wow! This is so simple and makes so much more sense than washing! Genius!

I just tried to do my first wash this weekend. After watching a lot of videos and looking at a lot of photos I couldn't tell if I was pouring trub or
yeast. My thin white line was really, really thin, so after all that messing around I'm not sure anything is even viable. This solution seems so much easier and so much cleaner! I will definitely do this on my next starter!
Thanks for sharing!

flips
 
Posted: 
November 14, 2012  •  01:27 PM
Is there a benefit to doing this rather than making a "glycerol" stock and putting it in the freezer?

I've tried using malt extract instead of glycerol as a cryo-protectant and it seemed to work just fine. Had to grow
up the starter culture days in advance though as I'd only made small aliquots.
 
Posted: 
November 14, 2012  •  06:38 PM
@bristela I'm afraid I'm nowhere near smart enough to provide a satisfactory response to this question... anyone else?
 
Posted: 
November 15, 2012  •  09:28 AM
Brilliant. This is one of those "Why didn't I think of that?" ideas. I will have to try this following my next batch, in which I am using yeast harvested the old-fashioned way ;)
 
Posted: 
November 16, 2012  •  08:51 AM
YES! I am about to make a starter for a brewday coming up. I think I may just have to pull some of this off and start saving my own "parent yeast" I live over an hour away from my LHBS and it would be nice to build a
"library" of sorts in my beer fridge of commonly used strains.

Thanks for taking the time to do the write-up man! Appreciate it!
 
Posted: 
November 16, 2012  •  10:31 AM
I'm confused by step 6

"decant about 80% of the beer off of the pre-harvested yeast in the larger mason jar, making sure to agitate to release the yeast from the bottom of the jar. Then simply pour the yeast directly into
the previously boiled water in the smaller mason jar."

Is the 80% discarded and the remaining 20% poured into the boiled water? If so, why would you agitate the yeast during decant? Wouldn't this mean that you're discarding
a large percentage of the yeast?
 
Posted: 
November 16, 2012  •  10:39 PM
Genius! I never thought washing the yeast after a full fermentation was a good idea, inbreeding over too many generations and all.
 
Posted: 
November 19, 2012  •  03:10 PM
@LeroyWhite Before agitating, pour off (decant) about 80% of the basically clear beer sitting on top of the yeast, then agitated the jar just to remove the yeast from the bottom... it's sticky stuff ;)
 
Posted: 
November 20, 2012  •  12:10 AM
Awesome!!! I have about 12 1/2pint jars in the back of the fridge holding multiple jars of washed yeast from 3 strains. SWMBO was a bit iffy at me taking up so much room in the fridge, but taking this approach will definitely cut
down on the necessary fridge space to keep my growing library :) Thanks, Brulosopher!!!
 
Posted: 
November 26, 2012  •  06:31 PM
I did this for the first time today and before I got the yeast going I went to the local hardware store and bought a pack of the pint mason jars. Now I have a bunch of these and was wondering if it is really necessary to now go
buy 1/2 pint mason jars as well. I would really rather be able to use another pint jar for the 6th step if possible to save on costs.
 
Posted: 
November 26, 2012  •  09:49 PM
Great post, thanks! One question I have is how can we determine how many billion cells are in that 500ml slurry? We know one vial or smack pack normally range from 100 to 130 billions.
 
Posted: 
November 26, 2012  •  09:55 PM
@Bisco_Ben Nah, it's not really necessary. In fact, I just harvested from 2 smaller jars then combined them a couple day later with the boiled water. Worked great!

@Royale I really have no clue how you'd get an accurate cell
count without using some sort of really nerdy lab equipment... which I kinda wish I had... but alas...
 
Posted: 
November 28, 2012  •  08:55 AM
Brulosopher - good stuff. I have saved some starter yeast before and also washed (well sort of) before too. I like your process and will start doing this for the next batch.
 
Posted: 
November 29, 2012  •  08:36 PM
When you are ready to make a 1000ml starter from the harvested yeast in the 250ml jar, do you use all of the yeast?
 
Posted: 
November 30, 2012  •  08:23 AM
How about this??? Make the big "1st generation" starter (say 1.5 liter), pitch half to new wort, refill starter flask with saved new wort made that day, 2 days later harvest about 4 jars of "2nd gen"...over
time, use 3 and when get to 4th, do this again and harverst 4 jars of "3rd gen".
I've been harvesting/washing yeast for a while but worry a little about generations as I've read things can start to stray in 4 or 5 gens.
(that said I've yet to detect any issues)
Thoughts?
 
Posted: 
December 2, 2012  •  11:30 AM
@onthedot Yep, easy-peezy

@Brewsday Sounds good to me, do it and report back. I don't like having all the yeast lying around, so 1 jar is good enough for me.
 
Posted: 
December 4, 2012  •  05:16 PM
A pretty well written tutorial but I would be a bit concerned about the dangers of superheated water in microwaves.

Perhaps an alternative of boiling water and then put into a ehrlenmeyer flask and foil capped separately from
cleaning/sanitising the mason jar would be safer?


http://en.wikipedia.org/wiki/Superheating
http://chemistry.about.com/b/2012/01/14/the-myth-about-superheating-water-in-the-microwave.htm
 
Posted: 
December 5, 2012  •  09:35 PM
@MaltyHops - Very, very good point. In fact, I've experience the superheat phenomenon and it's scary. For those concerned about it, I think your recommendation is a good one. For me, I'm comfortable with my current process.
Another option is to put a wooden stir stick in the water when you put it in the microwave. Thanks!
 
Posted: 
December 18, 2012  •  07:11 PM
Well I am here to report that I tried this method and so far it is a success!

I am making my first starter with harvested-yeast. I am making this one 500ml larger so I can continue to harvest yeast perpetually :)

Is there a
point when yeast has been over-harvested?
 
Posted: 
December 18, 2012  •  10:46 PM
@onthedot Some will say around 8 generations... but really, it's up to you!
 
Posted: 
December 23, 2012  •  02:00 AM
Very nice article. Good pictures too.
 
Posted: 
December 24, 2012  •  06:52 AM
Great article, thanks
 
Posted: 
December 28, 2012  •  10:55 AM
how long can i store the yeast in mason jars (without doing steps 5 and 6)before reusing them? and would i have to make a small starter before pitching?
 
Posted: 
December 28, 2012  •  12:18 PM
@sorefingers23 I would think 2-4 weeks would be fine; the deoxygenated water is simply a better medium for dormant yeast. I would definitely recommend making a starter before pitching- I always do. I just made a starter yesterday
using yeast I harvested 2 months ago and it took off within 8 hours.
 
Posted: 
December 30, 2012  •  03:17 PM
I have the say that I love this method! I looked into a few different methods of recycling yeast and this is by far the easiest and most convenient so far!

One question: Is there a picture of the 'proper' amount of yeast in the
final jar? I am not sure if I am cultivating the amount that I should, I think a visual comparison would really help both me and others.
 
Posted: 
December 31, 2012  •  01:24 AM
@onthedot I should take a couple pics and post them, but to answer quickly: I usually get about 1/2" of yeast at the bottom of the jar after a few days of settling.

Also, for those wondering about yeast viability, I found
this on the White Labs website:

"Generally, when reusing yeast from a fermentation, half of the yeast dies in the first month. So by 2 months you only have 10-30% living cells. For White Labs Yeast, the yeast is lab grown
with a special media and process, extending the shelf life. If you want to store yeast after fermentation, we would recommend a maximum of two weeks and releasing the pressure in your container every other day. Some people do go
longer than that, but the results are mixed. It is also difficult without a lab to check the quality of the yeast before reusing."

Of course they would prefer if we never harvested our yeast! Oh well. I just made 2 starters,
one from 3rd gen WLP002 and the other from a 4th gen WLP090- both took off quickly while on the stir plate and began vigorously fermenting 2 seperate IPAs within 8 hours. So...
 
Posted: 
December 31, 2012  •  09:04 PM
Bru - Thanks for the tip. This works great. I have more yeast than I know what to do with. I posted a few pics of this weekend's results here: http://www.homebrewtalk.com/f163/brulosophers-yeast-harvesting-testimony-377704/
 
Posted: 
January 1, 2013  •  07:29 AM
I wanted to thank the OP for sharing this idea. It has taken the cost of buying a $6 smack pack out of almost all of my beers. I haven't purchased 1056 in months!!

I do it slightly different. Rather than pitching half the
original starter into a fermenter, I toss the entire 2000ml flask in the fridge for a day. I then decant the spent beer off the top of that and split the remaining yeast cake up between 5 pint jars of boiled water. (I use the
method from this thread to boil/sanitize my jars/water ... http://www.homebrewtalk.com/f163/yeast-washing-illustrated-41768/ ) A couple days before brew day, I pull a jar out and build a starter for that beer. When I get down to
the last jar, I build another 2000ml starter and repeat the process of splitting it 5 ways.
 
Posted: 
January 4, 2013  •  09:38 AM
Well done Brulosopher, Great Idea and Great write-up, clean un-hopped yeast is exactly what Im looking for, as I also make all herb brews.

What do you use to make your starters with DME? or? and quantities?

Cheers!
 
Posted: 
January 8, 2013  •  07:08 AM
@WileECoyote Thanks, man! I use a ratio of 10 grams DME to 100 mL water; so for a 2.5 L starter that's 250 grams DME.
 
Posted: 
January 11, 2013  •  02:39 PM
Thank you, I was reading this while learning about yeast washing, etc.

But I would also like to point our the danger of superheating water in the microwave, it can happen, look it up on youtube.
 
Posted: 
January 11, 2013  •  04:24 PM
Great article. One thing though, if you cap your boiled water and then shake it to sterilize the jar lid, you're most certainly reintroducing oxygen into the water.
 
Posted: 
January 12, 2013  •  08:48 AM
@thetmaxx: This is absolutely true, so be careful! ;)

@gamb0056: Good point. I actually don't shake, but gently roll the jar so that the water touches all parts.
 
Posted: 
January 14, 2013  •  10:03 PM
Is the 500ML jar you end up with the equivalent of a wyeast pack or white labs vial? So you would just make a starter with this for one batch, and make 500ML extra to repeat the process?
 
Posted: 
January 21, 2013  •  11:26 PM
I use Mr. malty to calculate my starters.

What is the yeast viability date for this method? Do you use the date stamped on the original package of yeast from wyeast/white labs? Or do you use the the date you most recently
harvested from a starter?
 
Posted: 
January 21, 2013  •  11:54 PM
@onthedot I use the date I collected the sample. It's worked well so far.
 
Posted: 
February 7, 2013  •  10:07 AM
chiming in with others here on this magical post:
onthedot said:
"One question: Is there a picture of the 'proper' amount of yeast in the
final jar? I am not sure if I am cultivating the amount that I should, I think a visual
comparison would really help both me and others."

my question is in the post below:
 
Posted: 
February 7, 2013  •  10:54 AM
so, for your mini yeast samples (the ones in sterile H2O), how do you figure how much yeast from your sample to add to your starter to meet your appropriate pitching rate for your batch of beer?
 
Posted: 
February 8, 2013  •  06:56 AM
@mkravitz13 That's a good question. Unfortunately, I don't think too terribly hard about this piece of it, particularly since the amount of yeast that ends up in the jar (I'll try to add a pic) looks to be a tad more than what
comes in a vial. I make an ass out of u and me that there's roughly the same amount of healthy cells in my jars as there are in a vial. I've used numerous strains multiple times using this method and making a starter (I prefer
www.yeastcalc.com) using the date I collected the sample as the "manufactured date." If/when someone decides to do a cell count, my ears will be open. Either way, my beers have come out absolutely fantastic using this
method, better in fact than when I've started with a vial... this from some of my friends on tried and true recipes. So...

Cheers!
 
Posted: 
February 8, 2013  •  09:40 PM
What percentage of yeast solids would you estimate this method to yield?
 
Posted: 
February 9, 2013  •  09:57 AM
@d_striker I'm nowhere near smart enough to accurately answer this question. Umm, my best guess is "enough." ;)
 
Posted: 
February 11, 2013  •  11:12 AM
I'll add my thanks for posting the original method as well. I've been "attempting" the yeast washing from feremented batches for about a year now and have had mixed resluts. Your's definitely looks to be a better
method than I have been doing. One thing that may help with the issue of superheating jars, I have been boiling a quart jar and 4 to 6 jelly jars in water and then capping them full. I recently have had left over jelly jars that
I set aside and use that now sterile water to mix for my second washing. I intend to pre-boil/package sterile water/jars for use with your method. Avoiding the microwave altogether. I just have to dip the jar in star san
(closed ofcourse) before i uncap and pour.
 
Posted: 
February 11, 2013  •  02:23 PM
@lstrowge That's a great way to sterilize both water and jar, in fact I've done it before as well. I simply like the the ease of using the microwave. Cheers!
 
Posted: 
February 13, 2013  •  12:02 PM
First off, this is *awesome*...thank you! I think I might go about it like UofMontanaAlum suggested about just splitting the first starter up into several jars for refrigeration, rather than pitching any of that original starter.
Make new starters from those jars for use. Let's call it an initial harvest.

Secondly,
I'd like to recommend a slight clarification to Step 6 (recommended additions in CAPS):

"Step 6: The next day, decant about 80% of the
beer off of the pre-harvested yeast in the larger mason jar, WITHOUT DISTURBING THE YEAST ON THE BOTTOM. LEAVE 20% OF THE BEER TO HELP agitate AND release the yeast from the bottom of the jar. Then simply pour the yeast directly
into the previously boiled water in the smaller mason jar."
 
Posted: 
February 14, 2013  •  07:02 AM
@Weezy Thanks, I appreciate the clarification. Now if I only I had the ability to edit the original article ;)
 
Posted: 
February 17, 2013  •  07:21 PM
Great article bru. I was searching for this info a few days ago, why isn't this article stickied?
 
Posted: 
February 17, 2013  •  09:24 PM
@sethlovex A few people have suggested it be stickied; I think TxBrew is the person to contact for that :)
 
Posted: 
February 20, 2013  •  07:23 PM
Good post, this is pretty much exactly like what I've been doing since having similarly suspect results with washing. Since my stir plate and flask are capable of growing very large colonies of yeast (much larger than a 5 gallon
batch requires), it's easy to just make a little extra for later.

I haven't been transferring to the smaller jar with boiled/cooled water though, I'll give that a try.
 
Posted: 
February 21, 2013  •  12:20 PM
Maybe I'm just being really dense here but I'm not really clear on why this is so much easier than "Washing" (read: rinsing) the yeast to begin with. For all intents and purposes it's still seems like the same process,
just nailing it from the starter (and likely hopless) rather than the Primary. I'm not knocking it, I've done the same process previously and just used it as a base for a starter when I had two batches that were going to be down
near simultaneously but brewed at different times.
 
Posted: 
February 22, 2013  •  07:06 AM
@ fall-line: The sterilized/de-O2 water part is done only to provide a more hospitable environment for longer term storage. If you use the harvested yeast within 2-4 weeks, I'm not even sure that part is necessary.

@ Accidic: Not
dense at all! It's not really the same process because there is not yeast washing (really "rinsing") part to this method. You simply pour .5 liter of wort off of a starter and save it for later. This takes me a whopping
3 minutes. Harvesting and rinsing (multiple times) yeast that has already been used in a beer usually took me at least an hour, as I had to wait for the yeast to stratify, blah, blah. Plus I always ended up with 4 jars, which I'd
usually end up tossing 3 of. And yes, I absolutely prefer the fact the yeast I collect using the starter method is hop free, the only junk I collect is a little protein break material from the DME, which is no biggie. Hopefully
that clears some things up. Cheers!
 
Posted: 
February 25, 2013  •  03:36 PM
Brulosopher - good write up! I've been utilizing pretty this exact practice for the last year or so with outstanding results as well. I don't usually store longer than a couple months, so I actually don't decant my saved culture
from under the starter beer and have not had any problems.

Regarding estimating your cell count in the saved slurry that some people have asked about. Here is how I do it: Using the OP's example of 2.5L starter with .5L saved,
20% is kept. So if mrmalty/yeastcalc says my 2.5L has, for example, 220 billion cells, I estimate that I have kept 44 billion and use that + the date for the next batch. Given that is ~1/2 of a smack pack, stepped starters
really become your friend.

@Accidic - it seems a lot easier than washing/rinsing to me because there's very little trub to get rid of in 500mL of starter wort, so I don't bother with it. Also, when making a starter I'm already
in the kitchen with the stove on so getting a jar ready is easy while waiting around for my starter to boil. With washing I found myself either waiting to rack beers, or racking and just tossing the yeast anyhow because I didn't
have various sizes of jars sterilized.
 
Posted: 
February 26, 2013  •  07:01 AM
@ Jbear - I was thinking similarly regarding the cell count thing, I just didn't want to make the erroneous assumption my thinking was right ;). It makes a lot of sense to me, theoretically; however, what doesn't make sense is
that I end up with more yeast slurry in my jar than I've ever seen in a WL vial, which seems to contradict the idea there are only 40 million good cells in there. Also, I've never stepped up a starter using this method, even on
1.065+ beers, and they all get going within 12 hours and turn out fantastic. I'm admittedly confused... in a good way!
 
Posted: 
February 26, 2013  •  04:05 PM
Question - when you make a starter with an extra .5 liter, do you add 25% more DME?

I'm going to try this out 'cause I'm tired of buying yeast vials all the time...
 
Posted: 
February 26, 2013  •  04:19 PM
I don't have a microscope, so all I really have to base my assumptions is doing the math. I do agree with you that my saved batches appear to be at least the size of a vial, if not more. I have always figured it is mainly trub,
since we aren't washing/rinsing the sample. Its pretty clean trub, however, being an unhopped all DME wort only boiled for ~5 minutes so I think it blends with the yeast better. This explanation is my personal experience, but
unless all the yeast calculators out there are off by 100s of billions - I just don't see how we can have more cells than that.

In practice, I have not done many stepped starters either, because I rarely start it far enough
ahead of brew day for the extra chill/decant days. However, I'm brewing more 10 gallon batches these days I am starting to force myself to plan better. As an example starting with 97b cells (the yeastcalc.com default) you can hit
507b cells with a 5L starter. Or you can hit 506b with 2 1.4L starters. (all are stir plate numbers) Over time that 220grams of DME saved will add up!
 
Posted: 
February 27, 2013  •  07:09 AM
@ViperMan - Not necessarily 25%, as the amount of DME I use ultimately depends on the volume of my starter. Let's say a certain recipe calls for a 2 liter starter, usually I would use 200 grams DME. But if I plan to harvest some
yeast from this starter, I'd make it 2.5 liters and add 50 grams more DME. That said, there's been some very good conversation regarding the actual number of cells we're harvesting using this method... see Jbear's comment below
:)

@ Jbear - You make some good points, man. I'm really excited for someone who has the knowledge, skills, equipment, and interest to step up to the plate and count the harvested cells. It's so weird that multiple small volumes
of wort will result in more cells than a single flask with even more volume than the multiple combined. Huh.
 
Posted: 
March 1, 2013  •  01:04 PM
I stumbled across a fascinating thread that is discussing the very topic of yeast growth in starters. Several people there confirmed what I understood, which is that there is an ideal pitching rate specifically for yeast
propagation (which is different then the ideal fermentation pitch rate).

The thread then goes on to question whether sites like Mr Malty or Yeast Calc are accurate, specifically for stirred starters - which both you and I make.
Of the science oriented folks, the consensus seems to be they are fairly accurate for still/aerated starters, but some are seeing much larger growth than calculated with a stir plate. And that could certainly explain what you and
I see in practice - which is that jar sure looks like more than 40b cells!

Here's the link:
http://www.homebrewtalk.com/f163/stepping-up-yeast-starter-why-393288/
 
Posted: 
March 3, 2013  •  07:18 PM
@Jbear - Thank you so much for that link, I'm looking forward to perusing it. I'm glad I'm not the only one who seems to think I'm pulling way more than 40-50b cells.
 
Posted: 
March 4, 2013  •  10:28 PM
i think the next starter i make may have this in mind. since i usually go back and forth on 3 or 4 ale yeasts.
 
Posted: 
March 8, 2013  •  12:04 AM
Thanks Bru, been trying to decide the best way to get more than a few brews out of a yeast as I brew small batches and yeast is too expensive at one vial a batch. Think this looks like the best option.

Quick question: when you
first pour off 500 ml from the starter and place in the fridge do you have to worry about carb build up in the sealed jar or does the fridge temp stop any fermentation straight away. Don't want any jar bombs in the fridge.
 
Posted: 
March 8, 2013  •  06:46 AM
@RatsoRizzo - Personally, I've never "worried" about that issue or experienced any problems with it, as I only collect yeast after it is at least almost close to fermented out. Also, mason jars can take some pressure.
That said, is it possible to create bombs? Probably, but if your process is good and you're using good jars, I have a hard time seeing how it would happen. Cheers!
 
Posted: 
March 11, 2013  •  09:41 PM
The metal on the lid will fail long before the jar does. I know from experience. As far as I can tell, it's not from additional fermentation, mainly CO2 buildup. Just off gas as best you can before you can your yeast. Only one
lid bulged in the fridge, the other two failed when I took the yeast slurry out to warm up. Both times I got a faceful of yeast.

Bru, I'm using this method from some 1450. Just now coldcrashing a pint of the starter. The other
quart went into a porter I just brewed after work.
 
Posted: 
March 12, 2013  •  10:01 AM
Here's a question: I know breweries will use yeast 6-10 times with the best fermentations happening on the third or fourth round of reusing the yeast. What process is going on that improves fermentation and do you get the same
effect using this process (which I love...) or might this be an advantage to washing yeast the old fashioned way?
 
Posted: 
March 12, 2013  •  10:34 AM
@oldbullgoose - Hmm, I haven't a clue, really... but the second and third gens have produced fantastic beer!!
 
Posted: 
March 12, 2013  •  11:47 AM
Here's a question: I know breweries will use yeast 6-10 times with the best fermentations happening on the third or fourth round of reusing the yeast. What process is going on that improves fermentation and do you get the same
effect using this process (which I love...) or might this be an advantage to washing yeast the old fashioned way?
 
Posted: 
March 12, 2013  •  12:13 PM
@oldbullgoose - Deja Vu?
 
Posted: 
March 20, 2013  •  07:12 PM
Great idea. I'm going to try it with my next vial tomorrow. Is there any particular reason the final decant is into a 1/2 pint jar? Would there be a drawback to using pint jars for the final with air space? I possess way more
pint than 1/2 pint.
 
Posted: 
March 21, 2013  •  07:36 AM
@barleyfreak - I don't think it'd matter a single bit, I wrote this up for the person (ahem, myself) who would be purchasing new jars. Actually, if you have the ability and you plan to use the yeast rather quickly, it'd probably
be good if you collected a full pint of the starter, which you could then pitch directly into your next batch. Cheers!
 
Posted: 
March 26, 2013  •  04:09 PM
I am pretty new to brewing, 3 months. I think this is really great article and idea. I am deffinately going to start trying this. My wife is just about done with her Medical Lab Tech school and she said she can probably give me a
good count of the yeast cells. I think I will try this next week and hopefully post a good count.
 
Posted: 
March 28, 2013  •  10:48 PM
@humpadilo - I think many of us would truly appreciate a cell count!!!
 
Posted: 
April 3, 2013  •  10:25 AM
I've made a few starters using yeast I've harvested and every single one has been really aggressive. I used to be able to make a 2L starter in my 2L flask but all of the starters I've made with the harvested yeast have blown my
foil lid off and made a nice little mess on the counter. I'm assuming it's just because the yeast is much younger than it would be from the vial? I think it's time to buy that 5L flask I've been eyeballing.
 
Posted: 
April 11, 2013  •  08:01 AM
I love this idea. I've already got a mini fridge filling up with washed yeast as we speak. I wish I would have known about this sooner. And I agree with Taekwondd, I'm gonna need a bigger flask!
 
Posted: 
April 12, 2013  •  06:55 AM
@taekwondd - Haha. Yeah, I find myself using my 5L flask for lager/hybrid yeasts or for older yeasts. It works quite well. If 2L is the right size, pick up some FermcapS for about $2 and add a drop or 2 to your starter, it'll kill
that blowoff right good!

@mrkrausen - You go, boy, get that bigger flask ;)
 
Posted: 
April 14, 2013  •  11:07 AM
Awesome thread...Will definately be exploring this process. What a great idea. Will report back on progress.Thanks Bru! and others.
 
Posted: 
April 29, 2013  •  12:56 PM
I've been contemplating this lately. I was thinking about making a starter as soon as I get my yeast and then put part into a few jars to save for the next batch.
Thanks for the write up, this is a big help. I can do this right
when I get the yeast and have a few jars to use for my next few beers.
 
Posted: 
April 30, 2013  •  07:21 AM
@DanPoch - Right on, dude. While we're still unaware of exact cell counts, I tend to think pulling off a full pint will get your right around 100 billion cells (the same amount in the commercial packages); when my 1 pint mason jar
is in use, I'll simply fill two 1/2 pint jars then combine them later. Or, you could easily get away with building up a starter from the 1/2 pint pull, but I would recommend setting your "initial cell count" in whatever
calculator you use to 50 billion cells, just to be safe. Cheers!
 
Posted: 
May 2, 2013  •  10:18 AM
This is awesome, and I want to do this...

My question is this: How do you really know how many cells you have when you pour it off into your mason jar? Based on .5 liter, should we assume this equates to one vial of yeast if
bought? And, when you make a starter with this new yeast, what date are you entering in for production to calculate vitality when making a new starter? The date that you harvested?

Thanks for posting this!
 
Posted: 
May 3, 2013  •  07:36 AM
@arborman - Answers, in the order you asked:

1. We don't really know, we can just estimate. Using Kai's stirplate setting at YeastCalc.com, we can estimate there's approximately 100 billion cells. Anecdotal evidence suggests
however many cells are there works beautifully ;)

2. ! vial/smackpack has 100 billion cells... we estimate there's approximately 100 billion cells in our "pull" off the starter. Make of that what you will.

3. I enter
the date I harvested the yeast from the starter, yes.

Hope that helps. Cheers!!
 
Posted: 
May 6, 2013  •  02:06 PM
Great, thanks for the feedback.. So, lets say I have a vial of yeast that I want to bank.... If I do a 2500 liter starter with it, I can then break that down into 5 mason jars, and roughly go by each jar as if it was a vial of
yeast? If so, sounds like an easy way to build up a bank of yeast at home... Seems like more people would just do a starter for a batch, then add a bit extra to harvest... anything wrong with just doing a starter with the
purpose of harvesting all of it for future batches?
 
Posted: 
May 6, 2013  •  02:18 PM
@arborman - I see no problem with this at all, in fact, I've done it.
 
Posted: 
May 7, 2013  •  07:55 PM
brilliant! nice job sir.
 
Posted: 
May 7, 2013  •  10:47 PM
This is great, I too had many jars I couldn't use in a timely manner this the answer!! Thank you!
 
Posted: 
May 8, 2013  •  07:31 AM
@stvo - Glad you appreciate it! I currently keep between 4-6 strains of yeast on hands at all times, which allows for a great variety of beer. I also really enjoy sharing pulls with buddies.
 
Posted: 
May 8, 2013  •  12:14 PM
Wow Brulosopher, thanks so much for this novel approach! This is much easier than creating slants.
 
Posted: 
May 8, 2013  •  09:35 PM
i finally found pacman yeast locally but they rarely carry it so i will have to try this
 
Posted: 
May 9, 2013  •  06:50 PM
The advantage to pitching the proper amount of cells to an appropriately oxygenated wort, and letting it ferment to completion is to allow the yeast to complete the cycle and build up it's cell walls and and reserves and go
dormant as healthy as possible and be ready for the next batch.

One vial or smack pack is enough for 5 gallons of 1.040 wort. If you pitch that into 5 liters, won't the larger amount of cells use up the resources before they can
complete their cycle and go dormant in a healthy manner? Won't crashing before the yeast can complete it's cycle compound this issue? I believe you may be simply growing a bunch of very stressed yeast cells. A starter will grow
more cells from a new pack or vial or slurry but should be pitched while active.
 
Posted: 
May 9, 2013  •  10:14 PM
@sudsstud - I'm not sure where you get your info, and I'm certainly no microbiologist, but some of the best homebrewers out there crash their starters before pitching. Also, I know it's anecdotal, and I certainly know what a beer
made with stressed yeast tastes/smells like, but my beers are coming out very well. Cheers!
 
Posted: 
May 10, 2013  •  09:33 AM
This sounds so much easier than harvesting from a carboy after racking/bottling. It's obvious, in retrospect, though I never would have thought of this myself. Thanks for sharing...I know how I'm going to be harvesting my yeast
from now on.
 
Posted: 
May 10, 2013  •  10:13 PM
@Brulosopher - sorry I must eat my words. After 19 years of brewing, sometimes I think I know everything. After some research, I concluded that your method is legit.
I'll stick to rinsing my yeast post-fermentation just the same
but that's a nice article and technique. Kudos!
 
Posted: 
May 12, 2013  •  10:13 PM
thanks for the info brulo ! my question is ? I usually do a 36 gallons batches and I use 2 flask of 5000 ml I usually do a 3 lts starter with 3 vials per flask , if I using only one flask do I have to do a 4.5 lts starter and
then fill 3 jars and the remainder do it as I usually do ? or what will the best approach in this case ?

thank you !
 
Posted: 
May 12, 2013  •  10:17 PM
@santero - Those are huge batches! I'd mess around with the options over at YeastCalc.com ;)
 
Posted: 
May 13, 2013  •  03:59 PM
Nice post. I actually started doing this a little while back too. I bough a few expired tubes of White Labs yeast dirt cheap. I started with a very small starter and began stepping up. During the process, I realized that I had
nursed the yeast back to health and I could harvest directly from the starter and have a pretty good quality sample to bank for the future. I like the fact that it is an easier and cleaner harvest process and I store much less
volume of yeast in my beer fridge.
 
Posted: 
May 13, 2013  •  04:03 PM
I really like this method, i've been doing it for a few months. I then pour the yeast back into a white labs vial and it gives me a ballpark on my yeast numbers as related to the amount i buy.
 
Posted: 
May 16, 2013  •  09:13 PM
@BDun
how do you test for viability?
 
Posted: 
May 16, 2013  •  09:39 PM
@arborman - I don't...
 
Posted: 
May 17, 2013  •  11:11 PM
Have you ever let your starter wort settle & stratify, then decant off its trub before pitching yeast to collect the purest samples? That said or asked as the case may be, I've read articles that suggest there is some nutrient
value in the trub that benefits health yeast growth. Have you come across any information like this in your research?
 
Posted: 
May 22, 2013  •  12:00 AM
Yes I used to wash, but its all about the harvesting... Thanks Brulosopher
 
Posted: 
May 22, 2013  •  08:45 AM
@Chazmatic - I haven't... and I don't plan to. I'd be afraid I'd harvest only the least flocculant cells. Plus, this method has been working great.

@jeffd10 - Stop buttering me up.
 
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