Harvested yeast - first use and first harvested starter - experiences?

[KookyBrewsky]

Hello,

I randomly harvested this yeast a while back for some reason, at least half a year ago. Wyeast American ale, it’s been sitting in a mason jar in the fridge for a while.

My next brew will feature the same yeast, so I didn’t order a new batch. I have maybe 8-10oz worth of the yeasty, thick sludge.

I’ve been using starters for a while, but this time my stir plate barely latches except at max setting, and it’s the heavier duty one from Stirstarter. This yeast is thick, and I mean sludge supreme. I used just a bit more DME this time and dumped all the yeast in there.

Any advice or is all I can do cross my fingers and hope for the best? That amount of thick yeast sludge shouldn’t be too much?

 

[RM-MN]

While a shaken starter takes longer to get to the full number than a stirred starter the final number of cells will be nearly the same. I'd just shake that starter, at least until sufficient yeast was mixed in. Then I might use the stirrer again.

 

[IslandLizard]

Use a yeast calculator such as this one:
BrewUnited's Yeast Calculator

When you overshoot the inoculation rate (>100 million cells per ml) the growth rate will become lower.
Depending on age and such, your 12 oz of slurry may contain way too many viable cells for appreciable growth, but it will revitalize the cells you have.

Mr. Malty
Especially the "pitch from slurry" tab is handy to estimate viable cells vs. trub (and dead cell) content.

A typical fermentation increases the yeast content 4-5x. So a fully harvested slurry typically contains 4-5 times the number of cells you pitched.

 

[Dog House Brew]

Slurry viability can be tricky IMO. I just started some year old slurry. It took it about 3 days to get going. I generally start older yeast with 1.020 yeast. I then step it with about a quart of wort at 1.040.

 

[KookyBrewsky]

Slurry viability can be tricky IMO. I just started some year old slurry. It took it about 3 days to get going. I generally start older yeast with 1.020 yeast. I then step it with about a quart of wort at 1.040.

The slurry is extremely thick compared to the smack pack it came from though. Are the rates of present yeast the same per volume as a pack of thinner slurry yeast?

 

[VikeMan]

The slurry is extremely thick compared to the smack pack it came from though. Are the rates of present yeast the same per volume as a pack of thinner slurry yeast?

Usually, there's more yeast per volume in a harvested slurry than in a smack pack. But it depends on the thickness of the slurry and the percentage of non-yeast trub in the slurry. And that's before considering viability, which is influenced by the health of the yeast when it was harvested, how long it's been stored, and how it's been stored.

 

[KookyBrewsky]

Usually, there's more yeast per volume in a harvested slurry than in a smack pack. But it depends on the thickness of the slurry and the percentage of non-yeast trub in the slurry. And that's before considering viability, which is influenced by the health of the yeast when it was harvested, how long it's been stored, and how it's been stored.

When I watch videos most people have a thin layer of yeast they dump into the starter wort. Mine must've been mostly trub... it was 8oz + of pure sludge and I decanted it multiple times before storing it in a sanitized mason jar in the fridge where it sat for maybe 6 months. There was maybe a couple centimers of liquid remaining on top after the last decant and when I pulled it out yesterday to warm up and pitch. It smelled plenty yeasty when pitched.

I'm not sure this is feasible for a noob, there are too many guessing variables and I'd rather not destroy my brew, but at the same time, I kind of want to try it.

 

[Dog House Brew]

IMO, it comes down to time/age more than anything. Thick or thin, I have to see the activity in starter wort. When yeast takes 2-3 days to see any activity, I just want to see it alive. That is why you use low gravity wort. Soft start sort of. I visually gauge how healthy it is. Once I decant, I add normal strength wort and watch how quickly it comes on and how strong it is. It is a guess on “cell count”, but I’m more concerned with the activity. At this point the yeast is ready and hungry. I take some wort at 10min, decant the small amount of starter wort, add the batch runnings, and pitch. By the time the boil is complete the starter is already foaming. It isn’t quite at high Krausen though. Yeast health and activity conquers all wort! I always start on Monday when using any older yeast for a weekend pitch.

 

[Calder]

6 months is too long to be able to estimate the amount of yeast. Some will say it is dead, but my experience is that you can still use it. As a beginner, I would just pitch it in the beer and be done. Active fermentation may take a while (up to a couple of days), bit it will happen. Once it is going, all is good. It will produce beer, and decent beer if you keep it within the recommended temperature range.

Yes, there can be a discussion about the impact of under-pitching, but that shouldn't concern the beginner. Some yeasts produce desired flavors by under-pitching (Belgians).

 

[KookyBrewsky]

How about over pitching? Because this was a ton of thick trub/yeast so it’s hard to tell how much was there. I highly doubt I could over pitch but who knows how much yeast was in my harvest.

Here it is after 2 days. It really is a guessing game... I think it’s alive? There were no bubbles after 10 minutes of the stir plate being on, so I would imagine no amount of spinning would make bubbles appear unless the yeast are eating. It has tin foil on top so I can’t tell activity from an air lock.

 

[McKnuckle]

^Where is the wort? It seems like you barely used any, as it's up to only about the ~400 mL line. The point of a starter is to propagate new yeast cells, and to do that, you need enough volume for them to perceive that they need to multiply (however yeast do that). In other words, the yeast sample expands to fit its new environment. If you're not providing enough volume and nutrients, I don't think you'll get much (or any, in this case) growth.

If this were me, I'd wash the yeast in boiled/cooled water, let the trub settle for 20 minutes, then pour off the tan colored cloudy water on top into a new, clean jar. Let that settle in the cold, then decant the water and use the much smaller yeast sample to prepare a new starter.

 

[KookyBrewsky]

Do

^Where is the wort? It seems like you barely used any, as it's up to only about the ~400 mL line. The point of a starter is to propagate new yeast cells, and to do that, you need enough volume for them to perceive that they need to multiply (however yeast do that). In other words, the yeast sample expands to fit its new environment. If you're not providing enough volume and nutrients, I don't think you'll get much (or any, in this case) growth.

If this were me, I'd wash the yeast in boiled/cooled water, let the trub settle for 20 minutes, then pour off the tan colored cloudy water on top into a new, clean jar. Let that settle in the cold, then decant the water and use the much smaller yeast sample to prepare a new starter.

I used the same formula I have for every starter I’ve done. A pint of water and 1/2 cup of DME.

I can’t brew until the weekend and I could continue adding 1/2 cup DME + 1 pint for one or two more iterations. I did read about repeating the starter creation process multiple times where I first got my starter info.

Thanks for the tip. I think I might as well do that. It provides a better proof of concept than my haphazard hopes.

 

[VikeMan]

I used the same formula I have for every starter I’ve done. A pint of water and 1/2 cup of DME.

I highly recommend reading up on yeast starters and checking out one or more of the calculators. A one pint starter isn't of much use, unless you either don't need much growth, or you are starting with a very low cell count and the pint starter is step one of a multi-step starter.

 

[McKnuckle]

A more reliable way to prepare starter wort is by using a 10:1 ratio of water to DME. So for 1,000 mL of water, use 100g DME. 1,000 mL water weighs 1,000g, so it's very easy to weigh both the DME and the water on a metric scale. This gives you wort that's between 1.030-1.040 SG.

Your formula yields 473 mL water and 82g DME, 5.77:1 ratio, which is a much higher gravity wort. Just focusing on the overall starter volume for a moment; a 500 mL starter would be okay with a much smaller yeast sample, but not with a pile of slurry like you used.

 

[KookyBrewsky]

I highly recommend reading up on yeast starters and checking out one or more of the calculators. A one pint starter isn't of much use, unless you either don't need much growth, or you are starting with a very low cell count and the pint starter is step one of a multi-step starter.

I see. Well I’ve only used smack packs and that’s what the process revolved around. I suppose the smack and swell is the first step in the process. Otherwise I’ve only used dry yeast which needs no starter.

I’ll have to continue my research I guess. Brewing has always been easy, but yeast goes from knowing nothing to complicated very quickly. Not surprising since it IS the beer, basically.

Regardless I hope to get this harvested yeast primed for a weekend pitch...

 

[VikeMan]

I see. Well I’ve only used smack packs and that’s what the process revolved around. I suppose the smack and swell is the first step in the process.

FWIW, nothing about the little nutrient pack inside a smack pack changes anything about how big a starter is needed.

 

[BlutoA10C]

Agree with VikeMan and McKnuckle - the formula McKnuckle provided

A more reliable way to prepare starter wort is by using a 10:1 ratio of water to DME. So for 1,000 mL of water, use 100g DME. 1,000 mL water weighs 1,000g, so it's very easy to weigh both the DME and the water on a metric scale. This gives you wort that's between 1.030-1.040 SG.

is close to how I prepare my starters. I'm not very concerned with overpitching and I've had good success. I'm still very new to the homebrew team, but I used starters on my last four batches, all with excellent results.

 

[KookyBrewsky]

Agree with VikeMan and McKnuckle - the formula McKnuckle provided



is close to how I prepare my starters. I'm not very concerned with overpitching and I've had good success. I'm still very new to the homebrew team, but I used starters on my last four batches, all with excellent results.

I just prepared a starter with roughly that ratio, slightly less water, maybe 1:9.

Regardless my yeast has been washed, there’s nearly no trub now, there are three smaller mason jars filled with mostly a wort colored liquid, maybe lighter. I am going to pour all of that in the starter and the small bit of trub from one of them.

 

[BlutoA10C]

I just prepared a starter with roughly that ratio, slightly less water, maybe 1:9.

Regardless my yeast has been washed, there’s nearly no trub now, there are three smaller mason jars filled with mostly a wort colored liquid, maybe lighter. I am going to pour all of that in the starter and the small bit of trub from one of them.

Kooky - I admit to some laziness when it comes to washing the yeast. I try to pair the captured yeast with a similar brew. For example, if I capture the yeast from a stout, I pitch back into another stout. I doubt it would make a huge difference in taste at the end given the volume differences between the 5 gallon batch and a 1 liter starter. I also pitch the entire flask. I did try to measure out cells once based on a calculator . . . again, I'm a bit lazy and decided the overpitch wasn't that big a deal. If I start getting off flavors, I may re-evaluate. Cheers!

 

[KookyBrewsky]

Kooky - I admit to some laziness when it comes to washing the yeast. I try to pair the captured yeast with a similar brew. For example, if I capture the yeast from a stout, I pitch back into another stout. I doubt it would make a huge difference in taste at the end given the volume differences between the 5 gallon batch and a 1 liter starter. I also pitch the entire flask. I did try to measure out cells once based on a calculator . . . again, I'm a bit lazy and decided the overpitch wasn't that big a deal. If I start getting off flavors, I may re-evaluate. Cheers!

I am following a Two Hearted IPA recipe and it directly called for one of the only two yeasts I’ve harvested after many brews, so no matter how it turns out, I think the process is amazing. If all goes well I’m hoping I can stretch this yeast out for a very long time. It’s super cool no matter and exciting to try it out. I have a book called Yeast, part of the Brewing Elements Series. I didn’t finish it but I find the little buggers fascinating. Perhaps it’s time I finished it!

 

[BlutoA10C]

Yea, I've now "reused" basically the same batch of Safale US-05 4 times! I agree it's definitely interesting how the yeast does its thing and I get a weird sense of satisfaction from the process. Cheers!

 

[jerrylotto]

I'm following this thread with interest but I didn't see anybody mention how much of the harvested yeast to use. I've got a full mason jar of clean, harvested SO-4. Next batch I make I want to activate it but I don't see using the entire pint!

 

[VikeMan]

I'm following this thread with interest but I didn't see anybody mention how much of the harvested yeast to use. I've got a full mason jar of clean, harvested SO-4. Next batch I make I want to activate it but I don't see using the entire pint!

The amount of slurry to use will depend on what cell count you actually want for the batch, the thickness of the slurry, the percentage of non-yeast trub in the slurry, and the viability of the yeast in the slurry. Some of the yeast calculators support slurry calcs.

 

[jerrylotto]

Well that's fair enough but assuming that I have clean yeast and that it's settled out so that the slurry is basically nothing but a thick yeast paste - and it's only a couple of weeks old, what would the minimum amount be for a 5 gallon batch? I'm not doing a calculation for a specific batch I'm just trying to understand approximately what the ratio is.

 

[VikeMan]

Well that's fair enough but assuming that I have clean yeast and that it's settled out so that the slurry is basically nothing but a thick yeast paste - and it's only a couple of weeks old, what would the minimum amount be for a 5 gallon batch? I'm not doing a calculation for a specific batch I'm just trying to understand approximately what the ratio is.

So, you'd use a fairly high slurry density and a fairly low non-yeast solids percentage, and 14 days age in a calculator, along with your batch size and gravity. Even without the complications of a slurry, there's no standard answer for "How many packs of yeast do I need for 5 gallons?" And slurry makes the starting cell count a bit harder to estimate (vs. a new pack).

Sorry, but if you want to figure out how much to use for certain estimated pitch rate, you can't get there without the math. Calculators make it pretty easy.

All that said, if you don't care about pitch rate, use a half a cup. Or use the whole thing. Or use 2 tablespoons. There are plenty of threads where you'll see all of those recommendations.

 

[jerrylotto]

I'm not shy about using a calculator, and I'll take a look at a few of them. Since one pack of dry yeast generates close to a liter of slurry in clean wort when I ferment, I was just trying to figure out how much of the harvested yeast to save for my next batch. There's not much point keeping it beyond a single batch if I'm using the same strain.

 

[BlutoA10C]

I'm not shy about using a calculator, and I'll take a look at a few of them. Since one pack of dry yeast generates close to a liter of slurry in clean wort when I ferment, I was just trying to figure out how much of the harvested yeast to save for my next batch. There's not much point keeping it beyond a single batch if I'm using the same strain.

Jerry, I used this calculator: https://www.brewersfriend.com/yeast-pitch-rate-and-starter-calculator/ the first couple times I went through the process as I had the same questions as you. To be honest, given my conical fermenter, I usually capture 2 jars of predominantly yeast along with a little wort/beer as I change out the jars. When I make my starter, I simply pitch one 16oz jar - the jar usually contains about 4oz of "pack" at the bottom and the rest is liquid.

There are many recommendations available for "how to make starters", etc. and some involve decanting the jars, washing the yeast, etc. Refer back to my original comments - I'm lazy . Given I brew a 5 gallon batch, on average, every 4 weeks or so, I always have plenty of yeast for starters. I suppose if I was more rigorous in my process my beer would be "better", but I'm the only judge that counts and so far, I've been happy . Cheers!

 

[KookyBrewsky]

Well, I made a starter of 200ml total and used up all the yeast I had harvested after I washed it. I dumped the whole thing in. It was about 3 tiny mason jars worth of harvested yeast, I can’t recall the size. Had to be 4-6 oz. small thin layer of solids on the bottom of each, I mixed them in with one jar I poured in.

I brewed out front for a Halloween effect with my Hellfire burner and a glowing mask lol.

Here’s to hoping the yeast works... it smelled more like bread than bread does when I pitched it! About 9 hours later and no noticeable activity. But if this works I will be both amazed and ecstatic and begin learning more about how to correctly go about this process and how to calculate my needs better. Also, I will hopefully use this round’s harvested yeast sooner than 6 months in a fridge.

 

[VikeMan]

Well, I made a starter of 200ml total and used up all the yeast I had harvested after I washed it. I dumped the whole thing in.

Three mason jars of yeast into a 200 ml starter. That's not going to result in significant cell growth. Or did you mean 2000 ml?

 

[BlutoA10C]

Kooky, sounds awesome! Usually I have activity within approx. 12hrs or so. This depends, of course, on the yeast and type of brew, but that seems to be the norm for me. I mostly do ales, stouts, and wheat beers. There tends to be a little variance in the duration of "active" fermentation, but they all seem to start around the same time. Good luck!

 

[BlutoA10C]

Three mason jars of yeast into a 200 ml starter. That's not going to result in significant cell growth. Or did you mean 2000 ml?

VikeMan, I hadn't noticed the quantity, I was think 2 liter starter as well. I typically make 1 - 1.25 liter starters. Cheers!

 

[KookyBrewsky]

Three mason jars of yeast into a 200 ml starter. That's not going to result in significant cell growth. Or did you mean 2000 ml?

I dumped all the washed yeast I managed to salvage into a 1:10 ratio starter, using 1/2 cup DME and whatever the grams x 10 equivalent is in water, I believe around 650 grams.

There was bubbling and the smell was potent yeast/bread. There is now activity in my airlock.

Wouldn’t adding a half gallon starter negatively impact FG?

I have never had an issue in at least 10 starters worth, of using 1/2 cup DME and 2+ cups of water.

 

[VikeMan]

I dumped all the washed yeast I managed to salvage into a 1:10 ratio starter, using 1/2 cup DME and whatever the grams x 10 equivalent is in water, I believe around 650 grams.

There was bubbling and the smell was potent yeast/bread. There is now activity in my airlock.

Wouldn’t adding a half gallon starter negatively impact FG?

Again, it would really be a good idea to read up on starters and check out the calculators. A 200 ml starter is, in most cases, pointless. All it's really doing is proving you have live yeast.

And no, I wouldn't recommend adding a half gallon starter to your beer wort. I would cold crash when finished, then decant it, adding only (mostly) yeast to the beer wort.

 

[KookyBrewsky]

Again, it would really be a good idea to read up on starters and check out the calculators. A 200 ml starter is, in most cases, pointless. All it's really doing is proving you have live yeast.

And no, I wouldn't recommend adding a half gallon starter to your beer wort. I would cold crash when finished, then decant it, adding only (mostly) yeast to the beer wort.

I didn’t make up that information myself unfortunately

http://howtobrew.com/book/section-1/yeast/preparing-yeast-and-yeast-starters

 

[VikeMan]

I didn’t make up that information myself unfortunately

http://howtobrew.com/book/section-1/yeast/preparing-yeast-and-yeast-starters

I recommend reading the last paragraph on that page.

 

[KookyBrewsky]

I recommend reading the last paragraph on that page.

“for moderate strength beers 1-1.5 quart starters are sufficient.”

 

[VikeMan]

“for moderate strength beers 1-1.5 quart starters are sufficient.”

Right. Not pints or even less (200 ml). Also, understanding of growth curves and pitch rates has advanced quite a bit since 1999. That's where the calculators come in. For any desired pitch rate and estimated starting cell count, there's a particular starter size (or multi-step starter) to get there.

 

[KookyBrewsky]

Right. Not pints or even less (200 ml). Also, understanding of growth curves and pitch rates has advanced quite a bit since 1999. That's where the calculators come in. For any desired pitch rate and estimated starting cell count, there's a particular starter size (or multi-step starter) to get there.

This has been a multi step starter, the total water I’ve used is at least over 6 cups, 8 including washing after the fist starter.

Prior to this though I’ve not once had an issue with getting almost exact final gravities save for one partial all-grain batch that I had never done before using extract and all grain (before I switched to BIAB). I will possibly adjust for the future but I see no reason to change what is working based on experiential findings. Worst case I do multi step starters from now on because this batch is going nicely.

should a 2 cup starter with a smack pack be useless, perhaps I won’t use a starter at all with them because things have always been fine. Again this is my first non-new snack pack starter.

 

[VikeMan]

Prior to this though I’ve not once had an issue with getting almost exact final gravities save for one partial all-grain batch that I had never done before using extract and all grain (before I switched to BIAB).

That's cool. Reaching final gravity is not usually an issue, even when underpitching. There are, however, more common (off flavor) effects from underpitching.

But my point was that pint sized starters aren't increasing your cell count significantly. (i.e. regardless of how many cells you think you need, you're not really growing them.) But since this will be about the fourth time I've said this in this thread, I'll go on mute.

 

[KookyBrewsky]

Harvested yeast seems to be working without any noticeable sign of infection which is quite exciting, it smells absolutely amazing, possibly the best smelling brew I've done, then again I've never done an all-grain IPA until now. Today I added the dry hops.