Yeast Harvesting: A Novel Approach?

[oldbullgoose]

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?

 

[Brulosopher]

@oldbullgoose - Hmm, I haven't a clue, really... but the second and third gens have produced fantastic beer!!

 

[oldbullgoose]

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?

 

[Brulosopher]

@oldbullgoose - Deja Vu?

 

[barleyfreak]

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.

 

[Brulosopher]

@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!

 

[humpadilo]

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.

 

[Brulosopher]

@humpadilo - I think many of us would truly appreciate a cell count!!!

 

[taekwondd]

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.

 

[mrkrausen]

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!

 

[Brulosopher]

@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

 

[simie]

Awesome thread...Will definately be exploring this process. What a great idea. Will report back on progress.Thanks Bru! and others.

 

[DanPoch]

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.

 

[Brulosopher]

@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!

 

[arborman]

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!

 

[Brulosopher]

@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!!

 

[arborman]

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?

 

[Brulosopher]

@arborman - I see no problem with this at all, in fact, I've done it.

 

[mmonacel]

brilliant! nice job sir.

 

[stvo]

This is great, I too had many jars I couldn't use in a timely manner this the answer!! Thank you!

 

[Brulosopher]

@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.

 

[drtyhbo]

Wow Brulosopher, thanks so much for this novel approach! This is much easier than creating slants.

 

[troutcatcher413]

i finally found pacman yeast locally but they rarely carry it so i will have to try this

 

[sudsstud]

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.

 

[Brulosopher]

@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!

 

[GuldTuborg]

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.

 

[sudsstud]

@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!

 

[santero]

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 !

 

[Brulosopher]

@santero - Those are huge batches! I'd mess around with the options over at YeastCalc.com

 

[imrook]

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.

 

[diodeart]

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.

 

[arborman]

@BDun
how do you test for viability?

 

[Brulosopher]

@arborman - I don't...

 

[Chazmatic]

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?

 

[jeffd10]

Yes I used to wash, but its all about the harvesting... Thanks Brulosopher

 

[Brulosopher]

@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.

 

[Chazmatic]

@Brulosopher

 

[Chazmatic]

@Brulosopher
Good point. True enough, why mess with success?

 

[MachineShopBrewing]

For those who are wondering how many cells are in the slurry that you save. I have always used the mrmalty repitching from slurry tab to estimate the number of cells in my slurrys. If you have a graduated vessel you can measure the number of mls of slurry and use the mrmalty slider to estimate the number of cells based on volume. The default setting will take account for a normal level of trub.
I bought a bunch of 100ml- 1000ml flasks that I use for harvesting and measuring yeast. You can just pour it into a 500ml or 1000ml flask instead of the jar and cap it with saran wrap. Then, once it settles, you can keep in the 500ml or transfer to a 250ml flask with sterile water. The 250ml flask will make it easier to measure.
To use the mrmalty site to estimate yeast solids, just plug in a random beer number until it shows you the same number under "# ml of yeast needed" that you have in slurry. Then the " # of yeast cells needed (in billions)" number should be close to what you have as long as you leave the sliders in the default settings. Then you can plug that number into the yeastcalc.com site and figure out how you want to go about growing up enough for the next pitch.

 

[CraigerBrau]

I tried washing a couple times with the most recent being WLP002 out of an ordinary bitter. For all the reasons you listed, I decided it's not worth the effort.
Your method makes perfect sense and I can't wait to try it with my next starter. Thanks!