How much washed yeast to use in a starter?

[Yeastieboy]

After my last pilsner about four months ago, I carefully washed the German lager yeast from the fermenter. I have made plenty of starters from commercial liquid yeast. However, I have never made one from washed yeast. I will be brewing another 1.050 pilsner and would like to make an adequate starter. How in the world do I know how much of this washed yeast to use in the starter? I included a pic below. Any input is greatly appreciated!

View attachment ImageUploadedByHome Brew1484492197.596275.jpg

 

[drunkinThailand]

Your yeast looks pretty clean, I would say it has 1.5-2 billion cells per mL, call it 1.5 to be safe. Plus figure over 4 months you lost about 50%. So figure out how many mL you have, multiply that by 0.75 and that is how many billion cells you have (at least an educated guess about how many you have). Then use a yeast starter calculator to figure out your starter.

There are others here with much more experience/knowledge in this area, so if you're not in a rush maybe wait for one of them to chime in.

 

[jtratcliff]

Without cell counts your viable yeast amounts are just a WAG (wild ass guess) but DiT's estimates above as as good as any...

I tend to collect in 1/2 pint jars, decant the liquid after the yeast settles out then pitch whatever is left in the starter...

I don't get too hung up on how many billion cells I have... Since it's wildly inaccurate anyway

 

[IslandLizard]

What @drunkinThailand said.

It's 4 months old, so you probably want a fresh starter.

I'd say start from the end. According to your yeast calculator, how many cells do you need for your new pitch? Then plug in the starter size you want to make and see how many cells you need to start with. Fill in the harvest date to calculate actual vital cells.

Using an estimated 1.5 billion cells per ml of that thick slurry you have is probably conservative. This is before factoring in age. I'd look for pitching the minimum cells needed to make a starter that will yield your needed cell count in the end. That means you get maximum growth, maximum new cells. IOW, don't heavily overpitch your starter.

I prefer to use the calcs at Brewunited and Yeastcalc.

 

[Yeastieboy]

Thanks for the replies. I expect to make a starter versus pitching the washed yeast directly. Beersmith says I need 355B cells. I will probably just make a 2.5L starter (1.035) and inoculate it with half of the yeast from the large jar (about 100ml). Any major concerns with that plan?

 

[BitterSweetBrews]

That looks like a lot of yeast. Is that everything from the washing? I think you are on the right track. Using about half of it in a 2 - 2.5l starter should be plenty. Give it 2-3 days and if you have enough time in advance cold crash it a couple days and pour off the starter beer so you aren't diluting your wort.

I usually figure that if I have well washed yeast, I think of it in terms of the volume I would get and need in a White Lab or Wyeast vial and add 10-20%. This isn't very scientific but I like to keep it simple.

 

[KeninMN]

If I was brewing that beer I'd pitch the whole jar of yeast into a 1 liter vitality starter at the start of brew day and pitch the whole flask as soon as the wort is cooled to your preferred fermentation temperature. More information here:

http://brulosophy.com/2016/08/15/yeast-pitch-rate-pt-4-vitality-starter-vs-viability-starter-in-a-lager-exbeeriment-results/

I've had great success with this method using Saflager 34/70 slurry.

 

[Yeastieboy]

If I was brewing that beer I'd pitch the whole jar of yeast into a 1 liter vitality starter at the start of brew day and pitch the whole flask as soon as the wort is cooled to your preferred fermentation temperature. More information here:

http://brulosophy.com/2016/08/15/ye...ility-starter-in-a-lager-exbeeriment-results/

I've had great success with this method using Saflager 34/70 slurry.

I have never heard of a Vitality Starter. Intriguing for sure. Maybe this is a good opportunity to do exactly what you suggest above! Did I really read that you aren't supposed to aerate the batch? I assume that was talking about the starter and not the batch of wort?

 

[JONNYROTTEN]

I go against the norm, I almost always use a slurry and have never washed or made a starter with it. I just decant swirl and dump it in. With an low ABV 1.050 beer you would normally be fine. The 4 month of part is what could possibly give you an issue. Although probably fine I would never risk using yeast that old. Ive had slurry get funky after sitting to long.Also for whatever reason my slurries take off faster if left out overnight and pitched the next day like there revved up and ready to go.Getting it to room temp and pitching shortly after seem to have slower take off times.

 

[Yeastieboy]

Hopefully a starter will assist with the long time in the fridge. Visually, it looks good and i will definitely give it a good whiff before using [emoji6]

 

[sky4meplease]

Thanks for the replies. I expect to make a starter versus pitching the washed yeast directly. Beersmith says I need 355B cells. I will probably just make a 2.5L starter (1.035) and inoculate it with half of the yeast from the large jar (about 100ml). Any major concerns with that plan?

My experience would tell me if you made a 2.5L starter with 100ml of 4 month old yeast you might wind up with 200 billion cells.
If you can turn 50 billion cells into 355 billion with one step of 4 month old yeast I will buy tickets to watch you perform in Las Vegas.

 

[Yeastieboy]

My experience would tell me if you made a 2.5L starter with 100ml of 4 month old yeast you might wind up with 200 billion cells.
If you can turn 50 billion cells into 355 billion with one step of 4 month old yeast I will buy tickets to watch you perform in Las Vegas.

I take it you are still working on the constructive part of your reply? What would you suggest?

 

[sky4meplease]

I take it you are still working on the constructive part of your reply? What would you suggest?

You asked if there were any major concerns with your plan I merely expressed mine.
I personally would do a 2.5L starter of 1.020 wort, cold crash decant and do a 4L starter of 1.036 wort to get closer to your goal.

 

[Yeastieboy]

Fair enough. Would you suggest using the entire available yeast volume; about 300-350ml? ... or are you basing that on the 100ml of yeast?

 

[IslandLizard]

Needed 387 b cells of lager yeast for 5.5 gal of 1.050 wort.

Pitching 180 b cells (120 ml harvested slurry, estimated 1.5 b/ml) in 2.5 liter of 1.040 starter wort should yield around 432 b cells. Harvest date set at 8/1/16 (28% viability). It's a little low on the inoculation rate (20 m/ml). Growth rate would be ~7.6, although a little optimistic, I think that should work in one step.

 

[sky4meplease]

Fair enough. Would you suggest using the entire available yeast volume; about 300-350ml? ... or are you basing that on the 100ml of yeast?

I had you at about 75 billion viable cells to start.
If you have more than 100ml of clean slurry go ahead and use it.
With a sample that old I would play it on the safe side. Why push it?
I would suggest a lower gravity wort on your first step to wake things up. Your not going to gain that much by pushing the yeast hard straight away.
Given the wide range of potential viabilities I would still step the starter. The worst thing that could happen is you slightly over pitch.

 

[Sadu]

I just made a 1.060 pale ale with 3 month old slurry from another 1.060 hoppy beer. The 1 liter starter fermented out in about 4 hours and have never seen krausen like that in a starter before (made a big mess too). The cool thing about starters and allowing yourself some time is you can evaluate the yeast yourself and judge if it looks up to the job. In this case the calculators had it at 20 something percent viable but you could see it was healthier than that. I like to have the option to do another step if it looks necessary.

 

[jan_b19]

Just make a big starter with some yeast nutrient in it. 2-4 days you will have plenty of yeast.

 

[KeninMN]

For what it's worth, I've done overnight 2 liter starters (meaning 1 liter of starter wort + 16 oz of yeast slurry in a 2 liter flask) on a stir plate (this is key!) with yeast slurry that has been in my fridge for up to a year with no real problems (Wyeast 1084 Irish Stout). The average age of the repitched yeast I've used is around six months, as I currently stock seven different strains and don't typically brew the same styles back to back to back. I've done this for the majority of my brews over the three years that I've been brewing. I will say that I'm not a fan of repitching Safale US-05 or S-04. For that matter, I'm not a fan of US-05 or S-04 period, but I digress. The yeast in your picture looks great. Don't be afraid to use it or overly concern yourself with cell counts. Unless you're set up with the equipment to actually count cells you're only really guessing anyway. Your most significant contributors to success on a homebrew scale are sanitation, the quality of your ingredients, sound brewing and packaging practices and proper recipe design. The next step up from that is testing your water source or using RO or distilled water and building your mineral profile from zero, measuring everything you can with quality, calibrated equipment (temperature, weight, pH, specific gravity) and keeping detailed notes.

One final For What It's Worth, I don't wash yeast. In fact, what we call washing isn't actually washing at all (a process that requires the use of acid), and what you're actually doing is dumping the most viable yeast down the drain. I simply pour 16 oz of yeast slurry into a clean, sanitized pasta sauce jar and put it in the back of my refrigerator until I need it for a future brew. When I'm ready to use it I'll decant off most of the clear liquid, pitch it into a starter and spin it overnight if it's older, or start it the morning of brew day if it's younger (which I'll also do for fresh smack packs). Pitch the whole starter when your wort is ready.

Here is a really good article with more information: http://tobrewabeer.com/index.php/2015/06/24/yeast-viability-over-time/

 

[sky4meplease]

Your most significant contributors to success on a homebrew scale are sanitation, the quality of your ingredients, sound brewing and packaging practices and proper recipe design.

At what scale are those things not contributors to success? And...

Isn't Yeast one of the ingredients in beer?

One of the first things yeast do in wort is lower the PH. This is important for the yeast as well as providing an unfriendly environment for beer ruining organisms. The more viable yeast cells you have going in the faster this happens. So just from a sanitation standpoint pitch rates are important.
While revitalizing a 4-6 month old harvested sample will work and obviously a lot of people do it, it is not the practice or recommendation of professional brewers and brewing scientist.
I don't advocate using old ingredients including yeast even though you will technically still make beer with them. The older the sample of yeast the more care and feeding that should be done to bring it back to the proper health (if that is possible) and amount needed for the job.

 

[STMF]

One final For What It's Worth, I don't wash yeast. In fact, what we call washing isn't actually washing at all (a process that requires the use of acid), and what you're actually doing is dumping the most viable yeast down the drain. I simply pour 16 oz of yeast slurry into a clean, sanitized pasta sauce jar and put it in the back of my refrigerator until I need it for a future brew. When I'm ready to use it I'll decant off most of the clear liquid, pitch it into a starter and spin it overnight if it's older, or start it the morning of brew day if it's younger (which I'll also do for fresh smack packs). Pitch the whole starter when your wort is ready.

This is more or less exactly what I have switched to doing. I get quick, nice and clean fermenting and it fit nicely into my brewing schedule.

The only thing I sometimes do a bit diffrently is a quick rince before I pitch into the starter if there seem to be bit much trub in the jar.

 

[Yeastieboy]

This is all great information and I appreciate all your input on this topic. I practice pretty darn good sanitation and agree that visually, the jars of yeast appear "clean". I'm gonna give it a whirl this time. I will probably do something comfortably between those who make a starter the morning of brewing and those who suggest slowly building the starter. I may even build a starter using one of the jars just to see how quickly the yeast comes around. If it reacts well, I will have the other jar allocated for my wort.

 

[Yeastieboy]

View attachment ImageUploadedByHome Brew1485221401.434927.jpg
Well, here it is after a day. It looks super thick and creamy... like maybe too much yeast at this point. Maybe i will crash it and then build one more fresh starter the day before brewing (this Friday). Pretty much guesswork at this point. I feel like there is tons of yeast in there.

 

[Yeastieboy]

View attachment ImageUploadedByHome Brew1485262654.311429.jpg
...and this morning. Looks pretty good I think.

 

[sky4meplease]

If you want a cheap easy way to estimate cells get yourself a 10ml graduated cylinder with stopper, a10ml pipette and a pump (total estimated cost $25.00 all available on eBay). After your starter has completed, homogenize well and pipette 10ml of starter into the cylinder cap and refrigerate to settle and compact the yeast/trub.
After the sample has settled for 24 hours look through the cylinder to see how many ml is yeast/trub.
You will notice the different layers just like the ones in your last photo here. Dark layer on bottom is dead yeast and trub, middle layer is probably still suspect being higher floc yeast and dead yeast and the top layer being most viable.
Determine what percent is viable yeast and do the math to determine cells based on 1.5 billion cells per milliliter.
Example:
1,500 ml starter.
From your sample you determine .035 is viable yeast.
1,500 x .035 = 52.5ml
52.5 x 1.5 billion cells/ milliliter = 78.750 billion cells.
You would notice a starter built from fresh yeast would be mostly viable while these old harvested samples will yield more dead cells and trub.
View attachment ImageUploadedByHome Brew1485270166.560307.jpg

 

[Yeastieboy]

If you want a cheap easy way to estimate cells get yourself a 10ml graduated cylinder with stopper, a10ml pipette and a pump (total estimated cost $25.00 all available on eBay).

Great input. I may do that. So are you telling me that the only viable used in the picture below is the super thin white layer on the top!?

View attachment ImageUploadedByHome Brew1485349197.622302.jpg

 

[sky4meplease]

Certainly everything dead from your original sample is in that jar.
That could be up to 125-150 billion dead cells so yes it is possible those are your only vital and viable cells.
Looking at your last picture though when your starter was still in the flask it looked like you had a higher percentage of creamy white layer so it is also possible you have viable cells mixed in with the bottom layer.
Going back over this thread and your process I would guess you would have 75-100 billion cells at this point. Again only a guess.

 

[Yeastieboy]

The above is from the starter flask. I planned to make another 2L starter from this.

 

[sky4meplease]

The above is from the starter flask. I planned to make another 2L starter from this.

I think your on the right track.
When I max out my glass (3L) I go to making starters in buckets.
My 2 gallon buckets (for 1-1.5 gallon starters) fit right on my stir plate with a large stir bar and spin just fine.
I have done 2 gallon starters in a 5 gallon bucket and since I can't put that on the stir plate I just hit it with pure oxygen a few times during propagation.
This might seem excessive but I have found it real easy to max out my glassware and only get around 350 billion cells so I keep on going.
Some of my bigger beers and Lagers call for 600 billion cells and I don't think I could get that without moving up in volume.
Good luck and let us know how things work out.

 

[Yeastieboy]

Thanks. I think I'm on the right track tonight after the starters took right off. Thanks again!

View attachment ImageUploadedByHome Brew1485397499.271937.jpg