Simple Yeast Storage Procedure

[BroStefan]

But what about the beer in the mix? I will always get a different ratio of beer and "stuff." How do you account for that in relation to the numbers the OP found?

 

[WoodlandBrew]

Do I need to wait until I get a "hard pack" of yeast? How long might that take?

A couple of days in the fridge is normally sufficient. The rate at which the yeast settle decreases with time, so as time goes on your error would go down.

The OP is advocating NOT washing our yeast and instead just dumping the remnants from a batch of beer into mason jars and letting it settle out.
So in the mason jar(s) there will be a mixture of live yeast cells, dead yeast cells, hop debris, proteins and possibly other adjunct materials.

There will be "a mixture of live yeast cells, dead yeast cells, hop debris, proteins and possibly other adjunct materials" independent of the yeast being washed or not. Water washing yeast is good at removing compounds in solution but does a poor job of separating suspended particles.

See here for details:
http://www.woodlandbrew.com/2013/01/yeast-washing-revisited.html

But what about the beer in the mix? I will always get a different ratio of beer and "stuff." How do you account for that in relation to the numbers the OP found?

The numbers are averages based on hundreds of cell counts, but the deviation in measurement may be larger than expected. Variation by a factor of two is not uncommon. In the end, a factor of two isn't bad. Here is a paper talking about pitch rate and beer quality:
http://www.mbaa.com/publications/tq/tqPastIssues/1996/Abstracts/tq96ab09.htm

and some exBEERiments by the brulosopher:
http://brulosophy.com/2015/04/20/yeast-pitch-rate-single-vial-vs-yeast-starter-exbeeriment-results/
http://brulosophy.com/2014/09/15/sprinkled-vs-rehydrated-dry-yeast-exbeeriment-results/

 

[brewkinger]

There will be "a mixture of live yeast cells, dead yeast cells, hop debris, proteins and possibly other adjunct materials" independent of the yeast being washed or not.

Lol..
I did know this but since in a previous post I had been chastised for referring to yeast washing, I was hesitant to do so again.

The mixture would exist washed or unwashed yes....but would there still be a better ratio in washed yeast?

ie. More live yeast and less extra junk?

 

[BroStefan]

This has been very helpful for my understanding. This is what I gather this means about process.


Package the beer leaving about an inch behind.

Swirl it up THROUGHLY!

Pour into sanitized jars and let settle for at least a few days.

Decant most of the covering liquid. Stir up what is left and let that settle until it begins to stratifiy a little.

Pitch the appropriate based on the estimates in the first pitch and my desired pitching rate, leaving behind the bottom layer as much as possible.

If I am consistent about all of this I can learn over time how to adjust the assumptions of cells per ML

Is this a correct approach?

 

[christyle]

I'm not positive there is a need to decant until pitching really.

I haven't gotten into worrying about pitching rates....probably should....

 

[brewkinger]

This has been very helpful for my understanding. This is what I gather this means about process.


Package the beer leaving about an inch behind.

Swirl it up THROUGHLY!

Pour into sanitized jars and let settle for at least a few days.

Decant most of the covering liquid. Stir up what is left and let that settle until it begins to stratifiy a little.

Pitch the appropriate based on the estimates in the first pitch and my desired pitching rate, leaving behind the bottom layer as much as possible.

If I am consistent about all of this I can learn over time how to adjust the assumptions of cells per ML

Is this a correct approach?

Your approach sounds just fine.

As far as adjusting your assumption of slurry percentage, I do not bother.
Woodland's advice has not done me wrong on the last 3 batches.

I assume 1.5 million cells per mL of slurry (I wash my yeast) and thus far the starters I have made have been fermenting actively within hours.
There is no one factor that I could pinpoint as being the solution as I have focused on not only the size of the starter but also the temperature of the starter being the same as wort that I am pitching into.

What I do know for sure is that I enjoy harvesting the yeast and then reusing almost as much as actually brewing.
Saving $7 per batch is also a very happy thought provoking aspect as well.

 

[tarmenel]

Just wanted to post back saying I've just started my last batch with harvested yeast and it worked like a bomb.
Next question is how many times I can harvest the yeast like this? I'm not worried about it straying a bit to make my own home strain.

 

[Artifishal]

These other guys know way more about it than me but fwiw, I just kegged number 8 last night. Number seven was good, number six was amazing. I took number seven to my lhbs and they said a bit sweet. We dialed in to the fact that maybe my yeast are getting old and tired. Haven't tasted eight yet but of its not too sweet, I'm going to go with it for number nine.

It's a 7% IPA I keep doing over and over btw.

 

[brewkinger]

Just wanted to post back saying I've just started my last batch with harvested yeast and it worked like a bomb.
Next question is how many times I can harvest the yeast like this? I'm not worried about it straying a bit to make my own home strain.

5 harvests was the "suggested" rule of thumb in all of the reading that I did when I first started researching yeast.
I personally am on #7 harvest of WY1272
4th of 1056

11th of a Nottingham.

Like the above post, I found great success with all of the 3rd thru 5th harvests.

Someone in this thread indicated that they were up in the 20-30 harvest range of their yeast.
ymmv

 

[brewkinger]

Double post

 

[KartRacer54]

Part of these post suggest that the harvested yeast lose some through generations. If that is true wouldn't a starter cure that?
I have been reusing 1098 and 1056 but so far only a couple generations.

 

[tarmenel]

Great. So I'll just keep it going till it stops working. I'll save a bundle. Yeast is all dry here but still really expensive. Now just need to figure out how to grow hops in a Mediterranean climate

 

[tgmartin000]

I've harvested wy1450 quite a bit. I have a series of winter beers that all use it. Something like cream stout-oatmeal stout-black ipa-imperial stout, over the course of about 4 months. I think I went up to 6 generations, and at the end there was a marked difference in the flocculation of the yeast. But my imperial stout has been in secondary for 3 months now, so I'd imagine even a low flocculator will be settled by now.

I've also got some jester king slurry, as well as wy3724 Belgian saison. I've heard with that yeast, it doesn't stall out on generation 2, like with the first pitch. Looking forward to testing that theory.

 

[rhys333]

I've harvested wy1450 quite a bit. I have a series of winter beers that all use it. Something like cream stout-oatmeal stout-black ipa-imperial stout, over the course of about 4 months. I think I went up to 6 generations, and at the end there was a marked difference in the flocculation of the yeast. But my imperial stout has been in secondary for 3 months now, so I'd imagine even a low flocculator will be settled by now.

I experienced the same recently with ~9th gen 1469. I top-cropped that though and attributed the change to an ill-timed harvesting a couple generations before. Still flocc'd clear for me eventually, but it took 5 or so days longer than usual.

Edit: oops, you said 1450, not 1469.

 

[brewkinger]

Part of these post suggest that the harvested yeast lose some through generations. If that is true wouldn't a starter cure that?

It's not the quantity that gets lost as you harvest yeast.
The cells themselves can mutate with successive repeoductions. Get a wild strain or bacteria in with them and then as they are reproducing something happens and the resulting cells are "not quite the same "
This phenomenon occurs all throughout genetic biology.

 

[AnOldUR]

The cells themselves can mutate with successive reproductions. Get a wild strain or bacteria in with them and then as they are reproducing something happens and the resulting cells are "not quite the same. " This phenomenon occurs all throughout genetic biology.

Genetic mutation is rare without outside intervention. The change in finished beer character is more likely to come from harvesting methods. As you mentioned, wild yeast or bacteria is a big part of that, but sanitation aside, your harvesting technique will play a bigger part in consistency from batch to batch.

From Wyeast:

There are genetic variations within any population and these variations cause some yeast cells to exhibit different characteristics. Cells that flocculate early tend to be less attenuative and will settle to the bottom of the tank with trub. Cells that stay in suspension and flocculate later tend to be more attenuative and will end up at the top of the yeast bed. Repeated selection of either of these extremes will change the profile of the culture and alter fermentation characteristics.

 

[CGish]

Genetic mutation is rare without outside intervention. The change in finished beer character is more likely to come from harvesting methods. As you mentioned, wild yeast or bacteria is a big part of that, but sanitation aside, your harvesting technique will play a bigger part in consistency from batch to batch.

From Wyeast:

Is this part of why overbuilding the starter and setting part of it aside for next time allows for more generations than harvesting after fermentation? I have read that hops and stress play a part as well, but overbuilding does result in a cleaner looking yeast. Perhaps less opportunity to introduce impurities?

 

[AnOldUR]

Is this part of why overbuilding the starter and setting part of it aside for next time allows for more generations than harvesting after fermentation? I have read that hops and stress play a part as well, but overbuilding does result in a cleaner looking yeast. Perhaps less opportunity to introduce impurities?

Personally I think it's just the opposite, but would like to hear WoodlandBrew's thoughts.

I don't find that keeping trub to a minimum when harvesting from a fermenter that difficult, so don't see that as being relevant. Making a starter is making beer with the same chances for sanitation and selection related issues. Every time you handle the yeast (making a starter, splitting and storing a portion, making another start) you increase the risk. I believe that contamination is the biggest place where we see change in beer character from generation to generation and like brewing any beer, every time you make a starter should be considered as yet another generation away from the original yeast.

The lower gravity of a starter should give you more viability and vitality, but my thought is that direct pitching a large amount cleanly harvested yeast from your previous batch will offset this advantage.

For me, it's all about technique and timing. I can't just dump everything from the boil into my fermenter. I can't leave my beer on the yeast for 4+ weeks. I cold crashing my primary to aid in collecting more of the less flocculant yeast along with what has already dropped. The only drawback is leaving beer behind at various points, but by accounting for that up front I end up with the same amount of beer to the keg.

"Cleaner looking yeast" can also be had harvesting from your primary . . .

 

[rhys333]

I believe that contamination is the biggest place where we get change in beer character from generation to generation...

In my experience, another biggie is harvesting technique. As noted in the Wyeast quote above, selecting either early or late floc cells will change fermentation characteristics, sometimes dramatically. Woodland's simple yeast storage procedure addresses this by swirling the trub up before harvesting, evenly distributing early/late floc yeast cells. This helps preserve fermentation characteristics through the generations.

 

[AnOldUR]

In my experience, another biggie is harvesting technique.

I agree. That's why, like I said above, I cold crash before harvesting, although I've had better luck swirling with boiled water than using beer left behind after transfer like suggested in the OP.

It should be noted that those promoting taking a portion of yeast from a starter are subject to the same need to be mindful of harvesting technique. You have the same potential for selective collection.

 

[Yesfan]

I brewed an IPA that called for US-05 last night. Instead of using the packate that came with the brew, I used my slurry from a previous batch. The slurry is less than 5 weeks old, I didn't make a starter, but pitched the amount suggested by Mr Malty.

I pitched the yeast last night and was hoping to come home to some activity, but nothing. I know 05 can start out slow, but I was hoping the slurry would start a bit faster than the dry pack. Does the slurry usually start off slower?

 

[ahariton]

After reading through the thread I have a couple of questions - sorry if I missed the answers somewhere in the 18 pages:

1. If I'm using Mr. Malty to calculate how many ml of a slurry to pitch, how do I determine the viability? Do I use the harvest date? I primarily used liquid yeast and do all-grain BIAB if that makes a difference.

2. Once I know the slurry size from #1, how do I calculate the correct starter size to use? I use a stir plate

3. Some people have mentioned using chilled, boiled water to store the yeast instead of the inch or so of beer. Would reverse osmosis water be just as good if not better?

4. Is the harvesting exponential, meaning if made a starter with say 200 ml of slurry and used that in a beer, would the yeast continue to propogate, resulting in additional harvested yeast, or would I end up with same amount or less yeast after the beer?

Thanks

Andy

 

[christyle]

After reading through the thread I have a couple of questions - sorry if I missed the answers somewhere in the 18 pages:

.......

4. Is the harvesting exponential, meaning if made a starter with say 200 ml of slurry and used that in a beer, would the yeast continue to propogate, resulting in additional harvested yeast, or would I end up with same amount or less yeast after the beer?

Thanks

Andy

I can't give you good answers on 1-3 so I won't bother to introduce hearsay, but #4 I can: YES

The process of fermentation causes yeast to eat 02/sugar, poop C02/Alcohol, reproduce and die. This happens many times. Look at any beer you've brewed. Did you start with a packet and end with a packet? The yeast are multiplying greatly in this process. Thats the purpose of a starter, to increase cell count in preperation for being introduced into the larger main brew. You will get multiple mason jars full of good slurry you can then use in multiple other beers.

 

[Yesfan]

1). My last batch called for about 237 billion yeast cells. The amount of yeast in a slurry per 1 mil varies, so I stayed conservative and went with 1 billion/milliliter. Going with that, I just pitched about 300 mL of slurry from one of my jars. I've got a good krausen going on now when I checked it earlier today.

2) Look back in this thread as I think there was mention of how much DME you need per mL of slurry for a starter. Another way (just a guess on my part) is look and see if the Wyeast/White Labs packs tells you the amount of yeast cells in the pack. Maybe use that number to go by to give you an idea of how much slurry to use for a typical starter.

 

[ahariton]

2) Look back in this thread as I think there was mention of how much DME you need per mL of slurry for a starter. Another way (just a guess on my part) is look and see if the Wyeast/White Labs packs tells you the amount of yeast cells in the pack. Maybe use that number to go by to give you an idea of how much slurry to use for a typical starter.

Thanks.

Let me rephrase my starter question. How do you calculate how big of a starter you need to make to "wake up" the yeast. Is there a guideline for how big of a starter you need per billion (or 100 billion) yeast cells?

I think I remember reading somewhere that you can overwhelm a starter with too much yeast, eg you shouldn't pitch 300 billion yeast cells into a 1L starter.

Once I know the starter size I use 1the standard 10/1 water dme ratio.

 

[tgmartin000]

Thanks.

Let me rephrase my starter question. How do you calculate how big of a starter you need to make to "wake up" the yeast. Is there a guideline for how big of a starter you need per billion (or 100 billion) yeast cells?

I think I remember reading somewhere that you can overwhelm a starter with too much yeast, eg you shouldn't pitch 300 billion yeast cells into a 1L starter.

Once I know the starter size I use 1the standard 10/1 water dme ratio.

Why not use the yeast calculator at brewers friend?

http://www.brewersfriend.com/yeast-pitch-rate-and-starter-calculator/

Enter in the slurry amount and density, and it tells you what size starter to make.

 

[rhys333]

Why not use the yeast calculator at brewers friend?

http://www.brewersfriend.com/yeast-pitch-rate-and-starter-calculator/

Enter in the slurry amount and density, and it tells you what size starter to make.

That's what I do too. If I'm using relatively fresh slurry (i.e.: 1-2 weeks old) I just plug in the 1.5B cells/ml density Woodland recommends. He notes in the first post a half life of 3 months, so I've been guestimating approximately 17% cell loss per month (17×3 months =51%). On average I get the first signs of activity in 12-24 hours, which is about right I think. If fermention was to kick off in 4 hours though, I'd assume I over-pitched my yeast and the cell density was higher than the 1.5B estimate. Knowing that, I can adjust my calculations the next time I pitch a jar of the same yeast.

 

[ahariton]

Why not use the yeast calculator at brewers friend?

http://www.brewersfriend.com/yeast-pitch-rate-and-starter-calculator/

Enter in the slurry amount and density, and it tells you what size starter to make.

Exactly what I needed. Thanks!

 

[ahariton]

That's what I do too. If I'm using relatively fresh slurry (i.e.: 1-2 weeks old) I just plug in the 1.5B cells/ml density Woodland recommends. He notes in the first post a half life of 3 months, so I've been guestimating approximately 17% cell loss per month (17×3 months =51%). On average I get the first signs of activity in 12-24 hours, which is about right I think. If fermention was to kick off in 4 hours though, I'd assume I over-pitched my yeast and the cell density was higher than the 1.5B estimate. Knowing that, I can adjust my calculations the next time I pitch a jar of the same yeast.

Do you make a starter to "wake up" the yeast, or just pitch the slurry?

 

[rhys333]

Do you make a starter to "wake up" the yeast, or just pitch the slurry?

For anything under 8 weeks old I just pitch it directly. I've done it with older yeast too. I was hesitant to try it the first time, but the proof is in the pudding as they say. Longest lag time I experienced was about 36 hours, but once fermentation started, it went as normal and the beer tasted great. I would say do it and observe results. In the unlikely event you experience issues, you can always adjust next time.