Simple Yeast Storage Procedure

[thunderwagn]

I have a case of 1/2 pint jars (8oz) that I'd rather use than my qrt jars if possible just because I can fit them more easily in my fridge. Is it realistic calculating @ 1.5b cells x 236 ml for 355b cells? Just curious because on the OP, Woodlandbrew estimates 300b cells in a pint, so should I estimate half the cells (150b) for a half pint?

 

[rhys333]

I have a case of 1/2 pint jars (8oz) that I'd rather use than my qrt jars if possible just because I can fit them more easily in my fridge. Is it realistic calculating @ 1.5b cells x 236 ml for 355b cells? Just curious because on the OP, Woodlandbrew estimates 300b cells in a pint, so should I estimate half the cells (150b) for a half pint?

I store in 1 pint mason jars, but never use more than half the jar... so first I'd say you're fine using the 1/2 pint jars. If my stored yeast is under a month old I direct pitch the required amount. If its older I make a vitality starter to referesh what I have and build new cells.

For my BIAB process I typically estimate at 1-1.25B cells per ml with 15% cell loss per month of storage, but that's just what works for me from observations. I recommend you go with the 1.5B/ml and observe what happens. If the yeast seems active in the jar, its probably healthy and with a high cell count too (1.5B+). If your fermentation kicks off really quickly (as in 4-10 hours) the same applies. Conversely, if you get a long lag phase, say 36-72 hours, then you either have unhealthy or insufficient cells. For good pitching rates of healthy yeast, I like to see fermentation activity in 12-24 hours.

 

[thunderwagn]

I store in 1 pint mason jars, but never use more than half the jar... so first I'd say you're fine using the 1/2 pint jars. If my stored yeast is under a month old I direct pitch the required amount. If its older I make a vitality starter to referesh what I have and build new cells.

For my BIAB process I typically estimate at 1-1.25B cells per ml with 15% cell loss per month of storage, but that's just what works for me from observations. I recommend you go with the 1.5B/ml and observe what happens. If the yeast seems active in the jar, its probably healthy and with a high cell count too (1.5B+). If your fermentation kicks off really quickly (as in 4-10 hours) the same applies. Conversely, if you get a long lag phase, say 36-72 hours, then you either have unhealthy or insufficient cells. For good pitching rates of healthy yeast, I like to see fermentation activity in 12-24 hours.

Thanks. This go around I went ahead and used some qrt jars that I already had run through the canner with sterilized water. But I think I'll start doing half pints and pints. Full qrts seem to be a bit much for a single batch and the smaller jars will fit better in my fridge. I'd much rather do a vitality starter with smaller portions and have nice healthy cells.

 

[Jim311]

I use 8 ounce mason jars for 5 gallon batches of ales and have lag times that are astounding sometimes. I'm amazed by how fast and vigorous the fermentations are with 8 ounces of trub from the previous batch, even if they were stored 2 or 3 months.

 

[BroStefan]

I use 8 ounce mason jars for 5 gallon batches of ales and have lag times that are astounding sometimes. I'm amazed by how fast and vigorous the fermentations are with 8 ounces of trub from the previous batch, even if they were stored 2 or 3 months.

One thing I'm not yet clear on the density of the yeast in a jar. Say I follow the procedure - I stir up the yeast cake and pour it into 8 oz jars. In a few days it has settled into a dense yeast cake of some volume covered by beer for a total of 8oz. So is the volume that matters the 8oz I added to the jar I added to the jar in the first place or do I need to use multiple jars of dense settled yeast to get 8 oz total?

Yes, I'm probably over thinking this.

 

[rhys333]

One thing I'm not yet clear on the density of the yeast in a jar. Say I follow the procedure - I stir up the yeast cake and pour it into 8 oz jars. In a few days it has settled into a dense yeast cake of some volume covered by beer for a total of 8oz. So is the volume that matters the 8oz I added to the jar I added to the jar in the first place or do I need to use multiple jars of dense settled yeast to get 8 oz total?

Yes, I'm probably over thinking this.

Use the settled out volume, not the initial volume. E.g.: If you collect 8oz slurry and it settles to 7oz, then base your cell density calculations on having 7oz yeast.

 

[BroStefan]

Thanks. I finally clear.

 

[phug]

I pitched 250 ml of w34/70 frozen slurry into 3 gal of 1.037 wort yesterday afternoon at 60 f. I haven't seen any signs of activity yet. Trying to rdwhahb but it's difficult. First time that I've repitched from frozen.

 

[bratrules]

I pitched 250 ml of w34/70 frozen slurry into 3 gal of 1.037 wort yesterday afternoon at 60 f. I haven't seen any signs of activity yet. Trying to rdwhahb but it's difficult. First time that I've repitched from frozen.

It's going to take a few days to for that yeast to wake up. And 3 gallons is a lot of wort for amount of yeast. Just give it more time. You should see activity in a few days.

 

[brewkinger]

It's going to take a few days to for that yeast to wake up. And 3 gallons is a lot of wort for amount of yeast. Just give it more time. You should see activity in a few days.

I'm not sure I agree with above. Assume at minimum 1 billion cells per mL, which is conservative and that gives you 250B cells and that is more than enough for 3 gal of 1.037 wort.
Even at half that estimate, you have 125B cells and that is also plenty.

I'm not saying that you should worry phug.
The first time I used yeast that had been frozen, I had a slow start as well. I think that I had wrong ratio of glycerine and that was the culprit.
Are you sure that your process was good?

 

[phug]

Process was pretty straight forward and my glycerin quantity was measured by giant syringe. I'll give it one more day before I pitch some us-05 that I have on hand

 

[phug]

I was ball parking the math and had added 1 oz of 100% glycerin to a 225 ml bottle topped up the rest of the way with slurry. Admittedly this was 13% solution. It was also capped with crown caps. Then it has shaken to thoroughly mix in the glycerin. I placed it in the fridge for 2 days before moving it to the freezer at -20 c ( chest freezer with no defrost cycle)This was however me harvesting from a batch that I had previously harvested in the same manner minus the glycerin and stored in the fridge for a month before reuse and that batch did fine. It was from a 4.4% 12 ibu 12 srm batch and that one worked fine

 

[brewkinger]

I was ball parking the math and had added 1 oz of 100% glycerin to a 225 ml bottle topped up the rest of the way with slurry. Admittedly this was 13% solution.

I am thinking this may be your problem based on the math.

29.6mL of glycerine added to 225mL of distilled water (I assume) gives you a total volume of 254.6mL of glycerine/water.

29.6/254.6 = 11.6% by volume

Which you then further diluted with slurry, so your final concentration was lower than that.

I follow the guidelines in THIS article and it hasn't done me wrong (after my initial failure of course)

It basically starts out with 20% (I have even seen 25% in some literature) glycerine/water mixture and then added to slurry to get a 10-15% final concentration.

I have used vials of WY1318 and WY3711 (4-5 total brews) activated with a starter and they have taken off within 6-12 hours after pitch.
YMMV

 

[phug]

I am thinking this may be your problem based on the math.

29.6mL of glycerine added to 225mL of distilled water (I assume) gives you a total volume of 254.6mL of glycerine/water.

29.6/254.6 = 11.6% by volume

Which you then further diluted with slurry, so your final concentration was lower than that.

I follow the guidelines in THIS article and it hasn't done me wrong (after my initial failure of course)

It basically starts out with 20% (I have even seen 25% in some literature) glycerine/water mixture and then added to slurry to get a 10-15% final concentration.

I have used vials of WY1318 and WY3711 (4-5 total brews) activated with a starter and they have taken off within 6-12 hours after pitch.
YMMV

you're reading me wrong. I placed 29 ml of glycerin into an empty 225 ml bottle, and then topped up to the 225 ml volume with slurry. so 29 ml glycerin, 196 ml of slurry, which settled out to about 130 ml of dense slurry. So 29ml glycerin of a total of 225 ml of volume 12.8% glycerin in the final mixture.

I did see s low start with this yeast when it was dry pitched, but I had attributed that to it being my first 50F lager fermentaion and that the wort could absorb far more carbonation, as well as slower temps leading to more sluggish yeast activitiy. but this time I'm basically at Ale temps. so, I'll check again this afternoon, it will have been about 48 hours post pitch.

 

[brewkinger]

you're reading me wrong. I placed 29 ml of glycerin into an empty 225 ml bottle, and then topped up to the 225 ml volume with slurry. so 29 ml glycerin, 196 ml of slurry, which settled out to about 130 ml of dense slurry. So 29ml glycerin of a total of 225 ml of volume 12.8% glycerin in the final mixture.

Ha ha, I was literally just coming back to edit my previous post because that explanation occurred to me.

HOWEVER, this still makes me wonder.

You have 13% by volume in your method, but I wonder if that makes the actual glycerine/water ratio MUCH higher than expected. That article mentions that concentrations higher than 15% can actually be detrimental to yeast health.

 

[phug]

Yeah, it is higher than I was shooting for. Future batches will be lower concentrations, with better math

 

[brewkinger]

Like I said, use that article that I posted as a guideline.
1 part glycerine to 4 parts distilled water (20%).
Put slurry in 50mL vials and top off with the 20% glycerine and you will be golden.

 

[phug]

well, I'll definitely be trying this again, and we'll see if either the S-04 yeast, or the Vermont Ale yeast that I did on separate occasions stored any better. Who knows, I may be picking up some DME to actually use the stirplate I built and proof some of the stuff that I still have.

 

[brewkinger]

well, I'll definitely be trying this again, and we'll see if either the S-04 yeast, or the Vermont Ale yeast that I did on separate occasions stored any better. Who knows, I may be picking up some DME to actually use the stirplate I built and proof some of the stuff that I still have.

On that topic, I always make a small starter to wake up the little buggers from their frozen slumber.
It's just my preference.

 

[TurnipGreen]

Thank you all for the I for on this sticky. I successfully saved yeast using this method quite a few times. It's really fun and like all thinks brewing can be as simple or complex as you want to make it. I'm not doing anything too fancy. Usually just racking to a secondary and harvesting fresh slurry, storing it in the fridge and using it in within a month or so.

I have a batch that I was not planning to save from but I'm wondering if I still can. It's been sitting in the basement for about a month in the primary. Temperatures where controled for about two weeks (to hit the active fermentation) but over the last two weeks have been in the mid 60s and waiting to be bottled.

So, I'm certain there's still some good yeast in there, but is it worth salvaging? From my point of view if I need to make a starter I might as well get fresh yeast to avoid the gamble. But if there is still supper healthy fresh yeast like when I do it after a week of fermentation this could save me having to make a starter and in the future save a step of racking my regular easy drinkers that I want to save yeast from.

Any one have experience like this?

 

[rhys333]

Thank you all for the I for on this sticky. I successfully saved yeast using this method quite a few times. It's really fun and like all thinks brewing can be as simple or complex as you want to make it. I'm not doing anything too fancy. Usually just racking to a secondary and harvesting fresh slurry, storing it in the fridge and using it in within a month or so.

I have a batch that I was not planning to save from but I'm wondering if I still can. It's been sitting in the basement for about a month in the primary. Temperatures where controled for about two weeks (to hit the active fermentation) but over the last two weeks have been in the mid 60s and waiting to be bottled.

So, I'm certain there's still some good yeast in there, but is it worth salvaging? From my point of view if I need to make a starter I might as well get fresh yeast to avoid the gamble. But if there is still supper healthy fresh yeast like when I do it after a week of fermentation this could save me having to make a starter and in the future save a step of racking my regular easy drinkers that I want to save yeast from.

Any one have experience like this?

I've harvested and then repitched yeast that's been in primary 5-6 weeks without any issues. That said, it's also good practice to make a small starter for yeast that's been stored at room temp for that long. I wouldn't bother buying a fresh batch as long as your sanitation process on this batch was good.

 

[phug]

I pitched some of my "failed?" w-34/70 into a starter made of Malta Goya on my stirplate (first time I've used it for anything other than stirring water) and I'll be using that to see if they were totally toast, or just mostly toast. I used Malta because I didn't want to shell out criminal prices for DME locally, and i didn't want to spend a lot of time kicking off a starter I wasn't likely to actually use. SG of the Malta is calculated at 1.037 but man oh man is it dark. I wish it weren't so dark. Maybe I'll invest in some DME, or save some leftover wort and freeze it next time I brew.

 

[TurnipGreen]

I've harvested and then repitched yeast that's been in primary 5-6 weeks without any issues. That said, it's also good practice to make a small starter for yeast that's been stored at room temp for that long. I wouldn't bother buying a fresh batch as long as your sanitation process on this batch was good.

I pitched last night and I don't see any visible signs of activity. Every other time I've use this amount of saved yeast, activity has been visible within a couple hours. I'm trying my best to wait until tomorrow to start worrying.

 

[rhys333]

I pitched last night and I don't see any visible signs of activity. Every other time I've use this amount of saved yeast, activity has been visible within a couple hours. I'm trying my best to wait until tomorrow to start worrying.

First signs of activity in 12 -24 hours is ideal for me. Don't start worrying unless you pass the two day mark without activity. To clarify my earlier point though, smaller amounts of fresh, active yeast is better than large amounts of old yeast.

 

[phug]

I pitched some of my "failed?" w-34/70 into a starter made of Malta Goya on my stirplate (first time I've used it for anything other than stirring water) and I'll be using that to see if they were totally toast, or just mostly toast. I used Malta because I didn't want to shell out criminal prices for DME locally, and i didn't want to spend a lot of time kicking off a starter I wasn't likely to actually use. SG of the Malta is calculated at 1.037 but man oh man is it dark. I wish it weren't so dark. Maybe I'll invest in some DME, or save some leftover wort and freeze it next time I brew.

And today I checked the gravity on that starter and it was at 1.014. So clearly some of those cells made it through freezing and thawing. So I guess my last batch really got fermented with two strains of yeast

 

[thunderwagn]

Man, are Mr Malty viability rates just way out of whack? I've got about 800 ml of slurry that's 2 months old, and Malty's viability rate is like 10%. That seems incredibly low.

 

[rhys333]

Man, are Mr Malty viability rates just way out of whack? I've got about 800 ml of slurry that's 2 months old, and Malty's viability rate is like 10%. That seems incredibly low.

Yes, Mr Malty is overly conservative. I never use it anymore. You can estimate about 15% cell loss per month. So at 2 months yours is somewhere near 70%. If you bring it out of cold storage, crack the lid and air bubbles form in a few minues, viability is likely higher still.

 

[rhys333]

Help me make a judgement call guys. I pulled a jar of 3711 slurry out of the fridge thats about a year old. Top 1/8 inch layer is dead (dark cells). Under the lid there's a ring around the lip that's either yeast or a bug/lacto. I harvested this strain from a commercial beer ages ago and it always shows a very mild lacto film after fermentation, but never shows in the final beer. That said, the jar and top layer of contents look a bit sketchy. All that stuff around the rim is definitely new growth. Smells just fine though!

Anyone experienced this? Use or toss it?

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[David_Trucks]

Help me make a judgement call guys. I pulled a jar of 3711 slurry out of the fridge thats about a year old. Top 1/8 inch layer is dead (dark cells). Under the lid there's a ring around the lip that's either yeast or a bug/lacto. I harvested this strain from a commercial beer ages ago and it always shows a very mild lacto film after fermentation, but never shows in the final beer. That said, the jar and top layer of contents look a bit sketchy. All that stuff around the rim is definitely new growth. Smells just fine though!

Anyone experienced this? Use or toss it?

I vote toss it. At 1 year old, probably won't be very effective yeast anyway.

 

[daveMN]

I agree with tossing it. I tried making a starter with year old yeast, and it had a weird smell even after I stepped it up. Dark brown is not a good yeast color.