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Never wash your yeast again!!!!

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Don't seal up your mason jars when you collect yeast cakes. Even if you store them in the fridge. The yeast will continue offputting CO2 for a period of time and build up pressure. The pressure will end up breaking down the yeast cell's walls and killing your yeast. Place the lid on the jars and screw down the rings leaving enough room for gases to escape (like an airlock).

I have never had this problem. There is nothin in the jars left to convert.
 
Don't seal up your mason jars when you collect yeast cakes. Even if you store them in the fridge. The yeast will continue offputting CO2 for a period of time and build up pressure. The pressure will end up breaking down the yeast cell's walls and killing your yeast. Place the lid on the jars and screw down the rings leaving enough room for gases to escape (like an airlock).

If the yeast is done, and no fermentables are added, there isn't any risk of pressure build up any more than a bottled beer would have.

If the lid is loose, and gas can escape, then 02 can get it. For storage, the lid should be on securely.
 
Yes, that's good advice--pressure should not be the main concern, you will get burst jars before you get any pressure worth mentioning. When you are in your fridge or have to move them around, keep an eye out for bulging lids, just in case.

Been collecting straight slurry for a few years now. I screw the lids on tight and store in the fridge. Have never had a problem with a jar bursting. I don't believe enough CO2 is being released at that point to do any damage. At least, I've never noticed any. I currently have about 8 jars in my fridge. No issues. I do also give me beer plenty of time to finish up. I rarely rack/keg/bottle before 3-4 weeks from pitching.
 
I've heard the warnings about pressure build up, but never experienced it. If anything, the lid is hard to remove because a vacuum forms from contraction during chilling.


Note: I pitch cold
 
I use these for yeast storage, after washing and sanitizing. They are 1.75 liters. I was surprised by how much one had bulged and how much pressure was released when I loosened the cap. I leave the cap loose now.

You can write on these with a Sharpie.

simply-lemonade.jpg
 
If the yeast is done, and no fermentables are added, there isn't any risk of pressure build up any more than a bottled beer would have.

If the lid is loose, and gas can escape, then 02 can get it. For storage, the lid should be on securely.

As you can tell from my previous post... I 100% agree and have the history to back it up. The jars won't explode.
 
Don't seal up your mason jars when you collect yeast cakes. Even if you store them in the fridge. The yeast will continue offputting CO2 for a period of time and build up pressure. The pressure will end up breaking down the yeast cell's walls and killing your yeast. Place the lid on the jars and screw down the rings leaving enough room for gases to escape (like an airlock).

Despite what other may say, what mbbransc said above is accurate. There are a couple pages in Yeast that go into specific containers that are considered the best choices for storing yeast slurry. The best container recommended by Chris White is a stainless bucket with lid that fits over the rim of the bucket as it will keep airborne dust/particles out yet allow the venting of co2 which, when allowed to, will continue venting for quite a long time. Both the carbon dioxide AND the pressure inside a sealed container is detrimental to yeast cells. Granted, at the homebrew scale I think a bucket might be a bit overkill :D; however, something that can mimic the effects would suffice.

Sealed glass mason jars are not considered an optimal choice by Chris White due to the potential glass explosion factor and because of the screw-on lid. He states:

"If you use any vessel with a screw-on lid, leave the lid loose. Engage
only the first couple threads, which allows any pressure to escape
easily, but is secure enough that the lid will not fall off. In all cases you
can gain some additional protection by covering the top of the container
with a piece of aluminum foil." [White 2010:157-158]


You want to find out how much pressure/co2 is stored inside your tightly sealed jar? Shake it up, give 2 seconds, and try pushing down on the lid ;).
DON'T ACTUALLY DO THIS UNLESS YOU'RE PROTECTED.
 
Despite what other may say, what mbbransc said above is accurate. There are a couple pages in Yeast that go into specific containers that are considered the best choices for storing yeast slurry. The best container recommended by Chris White is a stainless bucket with lid that fits over the rim of the bucket as it will keep airborne dust/particles out yet allow the venting of co2 which, when allowed to, will continue venting for quite a long time. Both the carbon dioxide AND the pressure inside a sealed container is detrimental to yeast cells. Granted, at the homebrew scale I think a bucket might be a bit overkill :D; however, something that can mimic the effects would suffice.

Sealed glass mason jars are not considered an optimal choice by Chris White due to the potential glass explosion factor and because of the screw-on lid. He states:

"If you use any vessel with a screw-on lid, leave the lid loose. Engage
only the first couple threads, which allows any pressure to escape
easily, but is secure enough that the lid will not fall off. In all cases you
can gain some additional protection by covering the top of the container
with a piece of aluminum foil." [White 2010:157-158]


You want to find out how much pressure/co2 is stored inside your tightly sealed jar? Shake it up, give 2 seconds, and try pushing down on the lid ;).
DON'T ACTUALLY DO THIS UNLESS YOU'RE PROTECTED.

There's theory and then there's real life practice. In theory, communism works great! But in real life, not so much. (Just joking around here. No need for a heated political debate.) The point being I understand the reasoning behind this, but I've never noticed an issue in real life practice. I have seen just the opposite. I've notice a lid one or twice having reverse pressure due to the cold and the lid actually pulling in a bit. Again, nowhere near enough to cause any issues.
 
There's theory and then there's real life practice. In theory, communism works great! But in real life, not so much. (Just joking around here. No need for a heated political debate.) The point being I understand the reasoning behind this, but I've never noticed an issue in real life practice. I have seen just the opposite. I've notice a lid one or twice having reverse pressure due to the cold and the lid actually pulling in a bit. Again, nowhere near enough to cause any issues.

I understand that seeing is believing.... maybe that's why I'm agnostic :D
 
If you're experiencing exploding mason jars, there's a reason for it. Your beer was not done fermenting when you bottled up your yeast.

Personally I've never seen or heard of one exploding and I'm not convinced that it's possible. The lid is designed to relieve pressure after a certain point.
 
If the yeast is done, and no fermentables are added, there isn't any risk of pressure build up any more than a bottled beer would have.

If the lid is loose, and gas can escape, then 02 can get it. For storage, the lid should be on securely.

This is good sense in theory, but when I jar mine there must be some residual dissolved CO2 offgassing from the transfer, because there is definitely pressure. I have had some produce enough pressure to make the bands hard to unscrew. These are batches that are most definitely done, ones that were bottle primed and carbed correctly--i.e. no residual sugar. I am usually a four-week primary kind of guy anyway.

Gravity on the lid will keep O2 out, anyway. Loose bands won't permit inbound air unless you have a hurricane in your fridge, they just permit gas to escape.
 
If you're experiencing exploding mason jars, there's a reason for it. Your beer was not done fermenting when you bottled up your yeast.

Personally I've never seen or heard of one exploding and I'm not convinced that it's possible. The lid is designed to relieve pressure after a certain point.

I haven't had one explode from this, but Mason jars are not pressure vessels and there is nothing whatsoever about a Mason jar lid that should make you think "safe release".

There is probably not enough residual CO2 in the vast majority of jars of slurry to cause an explosion. Probably isn't a word I like to use around pressurized glass vessels that aren't made for pressure.

As you can tell from my previous post... I 100% agree and have the history to back it up. The jars won't explode.

A history of something not happening is unconvincing when held up against that thing happening just once, isn't it? Like I said, I haven't had explosions, but I can a lot and I know "jar under pressure" when I see it, and it's not something to tell people on a forum to ignore when there's a broad base of people saying it's a real risk.

There's theory and then there's real life practice.

Yes, the theory is that there should be no CO2... though I think that's a pretty flawed theory because it assumes the only source of CO2 release would be continued digestion of sugars. I don't know if offgassing dissolved CO2 explains it either, but it's obviously real from reading testimony in this thread (and Chris White) even if its appearance apparently depends on some unknown conditions.

But, as I can't imagine I have anything else to say about this, unless I come with photographic evidence I'm going to step out now.

My warning to anyone reading who hasn't tried this: Leave your bands loose, just in case.
 
A history of something not happening is unconvincing when held up against that thing happening just once, isn't it? Like I said, I haven't had explosions, but I can a lot and I know "jar under pressure" when I see it, and it's not something to tell people on a forum to ignore when there's a broad base of people saying it's a real risk.

Just posting my experience with probably somewhere a little under 100 jars of yeast saved. Never had one explode. Maybe I shouldn't say "It won't explode".... but I have never seen it.... again, after close to 100 jars. I'd say that's a good sample size, no?

EDIT: So why not ask? Has anyone ever had a sealed mason jar of yeast, in the fridge, explode?
 
Yes, the theory is that there should be no CO2... though I think that's a pretty flawed theory because it assumes the only source of CO2 release would be continued digestion of sugars. I don't know if offgassing dissolved CO2 explains it either, but it's obviously real from reading testimony in this thread (and Chris White) even if its appearance apparently depends on some unknown conditions.

People love to add words and thoughts to quoted posts. Always cracks me up. I never said no CO2 is released. There may be. I don't know. All I know is my experience. My beers sit on the yeast cake for an average of 3-4 weeks (occasionally 2 weeks, but extremely rare). I swirl the cake, pour into 3-4 sanitized jars, seal the lid, and pop them in the fridge. I've done this somewhere around 25-30 times, 3 - 4 jars each time = around 100 jars. I have never had one explode and usually the lids aren't even tight to remove. Yes, occasionally they are a little tight, but there is no where near enough pressure to make the jar explode. That is all I'm saying. And these are MY experiences. No scientific data. No blanket statements. Just my experiences. Take from it what you will.

EDIT: My bad... this wasn't quoting me. My apologies, but the rest of my statement is still accurate.
 
OK, I promised to step out not five minutes ago, but for real: Are you debating whether there can be pressure buildup, or just the extreme point about explosions? Because if you admit pressure you have to admit there's risk (unless it's just rhetorical debate game and we're keeping score).

A relevant question: Has anyone ever seen obvious signs of considerable pressure buildup in a sealed mason jar of yeast, in the fridge?

Oh hey we have an answer, yes, more than one of us. So if you like your fingers where they are, be careful and consider loosening those bands. Done now, pinky swear.
 
OK, I promised to step out not five minutes ago, but for real: Are you debating whether there can be pressure buildup, or just the extreme point about explosions? Because if you admit pressure you have to admit there's risk (unless it's just rhetorical debate game and we're keeping score).

A relevant question: Has anyone ever seen obvious signs of considerable pressure buildup in a sealed mason jar of yeast, in the fridge?

Oh hey we have an answer, yes, more than one of us. So if you like your fingers where they are, be careful and consider loosening those bands. Done now, pinky swear.

I'm not debating anything. As I've stated repeatedly, I'm simply sharing my experience. Not everything on here is a debate.

And yes, you'll be back with a comment.
 
I haven't had one explode from this, but Mason jars are not pressure vessels and there is nothing whatsoever about a Mason jar lid that should make you think "safe release".

The lid will lift enough to relieve some pressure at a certain point.

If you know of one that has exploded, please share that with us.
 
The lid will lift enough to relieve some pressure at a certain point.

If you know of one that has exploded, please share that with us.

It will skip out of the threads? How? Every time? We can test this out with dry ice if you'd like. I uh, mean to say you can test it! I'll be over here. :)


And yes, you'll be back with a comment.

And yes, here I am replying. I don't mean to seem confrontational, it's just weird to see so many people not urging caution. Mason jars are simple, simple containers, the lids do not have some kind of invisible pressure failsafe! Scary stuff, man.
 
Hello, That cost way to much at $8 a vial especially when your using liquid yeast and brewing a 10 gallon batch every other weekend. :D

Cheers :mug:

Agreed and even for 5 gallon batches. I currently have 2 large jars of lager yeast, 3 medium jars of belle saison yeast, 1 large jar of irish ale yeast, and 1 large jar of wheat yeast. So they started from 4 original packs at $8 each. That's $32. I've already repitched or traded some of the collected yeast for others, but lets forget about that. Those 7 jars are equal to another $56 worth of yeast and probably more considering the large jars. One large jar of lager yeast is WAY more yeast than a packet of yeast. So really, those jars probably all equal close to 12-13 packs of yeast. 12 packs at $8 pack.... you're now pushing close to $100 worth of yeast. The amount of money that can be saved is just ridiculous.
 
Mason jars can and will pop if pressurized! I had a litre of trub/yeast/liquid spill all over my fridge when the "safety release glass" exploded due to residual yeast activity.

Just leave it slightly open and learn from my mistakes.
 
Hello, I read what most people are doing, I do a combo.

1. With a new vial of yeast I make a huge yeast starter like the OP was saying and divide that into 6 to 8 quarts and 2 pints, then store in fridge until needed, this would give me 8 to 10 batches from 1 vial.

2. I start off using a jar of yeast with the first batch of beer being a wheat beer, after racking, I transfer right on the yeast cake with a bit stronger batch of beer like a amber, then next time a dark beer, I only use the yeast cake a maximum of 4 times then toss it out.

Now add this to the 8 to 10 batches by doing #1 and you get 32 to 40 batches out of 1 vial of yeast.

This has cut my yeast cost tremendously and I have had not had any off flavors from doing this.

It dose take some beer brewing planing though !

Cheers :mug:
 
I pitched (2) mason jars of yeast this past weekend that were harvested 3wks prior. I screwed the lids on tight. Both mason jars were pressurized and one was evident by its bulging lid. Did I cold crash and bottle too soon? Maybe. Oddly enough, that beer is undercarbed. Figure that one out.

But I pitched those two jars into a 1.100 imperial stout and a 1.048 APA and have had no activity for 5 days. So I did some research and found that yeast trapped in a pressurized vessel with CO2 will rupture their cell walls and die. So I'll be pitching some US-05 in those batches.

My point that sparked all of this was not exploding mason jars (which I do believe is possible) but yeast health. Maybe the best practice should be to harvest the yeast and maintain in a mason jar with a loose lid for 1-2 days, then tighten it down. That way you're sure the yeast are dormant if there were still active yeast and fermentables at harvest time.

Glad some are positive there are no dangers and bank on theories. Likewise, I'll use my experiences and adjust accordingly.
 
Hello, I read what most people are doing, I do a combo.

1. With a new vial of yeast I make a huge yeast starter like the OP was saying and divide that into 6 to 8 quarts and 2 pints, then store in fridge until needed, this would give me 8 to 10 batches from 1 vial.

2. I start off using a jar of yeast with the first batch of beer being a wheat beer, after racking, I transfer right on the yeast cake with a bit stronger batch of beer like a amber, then next time a dark beer, I only use the yeast cake a maximum of 4 times then toss it out.

Now add this to the 8 to 10 batches by doing #1 and you get 32 to 40 batches out of 1 vial of yeast.

This has cut my yeast cost tremendously and I have had not had any off flavors from doing this.

It dose take some beer brewing planing though !

Cheers :mug:


I do something similar to this but skip starters. Let's use WLP090 as an example.

I'll brew a 6gal batch of 1.050 APA and split it between (2) vessels. In one I'll pitch the vial of WLP090. When I rack off the yeast cake, I'll dump a 5.5gal 1.060+ IPA on top of it. When I rack that IPA off, I'll harvest half the yeast cake in a couple mason jars and dump fresh IIPA on the other half. I'll usually throw it out after that and start with my (2) harvested jars back with another IPA on each jar. So I'm thinking I get about 6.5 batches of 5gal beer off a vial of yeast. I guess that gets the cost down to nearly $1 a batch.
 
Any effects using a slurry that came from a dry hopped batch?

If you mean dry hopped with pellet, I haven't/don't because I'm concerned that too much vegetable matter for too long is probably not a positive. I don't know how bags would impact that either. I usually dry hop with bagged leaf and have had no difficulty.
 
If you mean dry hopped with pellet, I haven't/don't because I'm concerned that too much vegetable matter for too long is probably not a positive. I don't know how bags would impact that either. I usually dry hop with bagged leaf and have had no difficulty.



Yes, meant with pellets. I dry hop with pellets directly in primary, no bags.


Sent from my iPhone using Home Brew
 
It's not a debate to me. I believe what Chris White wrote in Yeast.

I, personally, use glass canning jars to store my refrigerated yeast. I choose to keep the bands tightened to a point where they contact the lid with ever so slight pressure. I do this to allow co2 to escape during the storage period. I can hear a faint trickle of hissing/sputtering from co2 escaping some of my yeast jars going on for weeks after storing in the fridge. I also don't worry about exploding jars because I doubt that under refrigeration there will be sufficient pressure to cause an explosion PLUS my lids are not cranked on tight so pressure can easily escape. Most of my jars all have positive pressure which is easy to tell by simply pressing on the lid. The reason why we always have some amount of co2 buildup in stored yeast is because yeast cells bind to co2; however, some strains have a tendency to bind less. Generally speaking, the more flocculant the strain, the less it binds.

CO2, pressure, container choice, storage length, etc. I only pay attention to these things as much as it affects my yeast quality, viability, and vitality. I have learned a lot from reading scientifically-oriented blogs and books on the subject of homebrewing and yeast. I have changed some of my practices in yeast handling because of it. Some others I should change but they're not worth the effort for me at this time. Simple things like keeping a lid ever-so-lightly snug is an easy change to make with a potentially large payoff, IMO.

Here's something I just did the other day while a beer was boiling. I pulled a pint jar of harvested yeastcake out of the fridge. It was about 2/3 full of yeast with beer sitting on top. I poured the beer into a glass and drank it (mmm, it was really good). I sealed up the 2/3s-full jar of yeast and gave it a good shake to break it up and get it ready for pitching. I knew the pressure would build so I gave it 30 seconds to let the yeast slide down from around the rim of the jar and loosened the band to relieve the pressure, and left it this way until pitching time. When pitching time came around about 90 minutes later, the yeast was almost up to the lid due to the sheer amount of carbonation contained within the jar. You could literally see that the yeast was in a foamy slurry due to the amount of co2. It's pretty amazing really because you wouldn't think there's that much co2 contained within a jar of harvested yeast. If you're willing to waste a jar of yeast slurry, and a little bit of time, try this out yourself; if for no other reason to see the foam slurry.

One last observation I've noticed throughout my yeast harvesting procedural changes is that well-rinsed yeast does not retain the co2 like yeastcake does. I suspect that part of the co2 is evacuated through the rinsing process itself, and after crashing, I used to replace the top rinse water with sterile water which is obviously void of co2. I don't practice the rinsing and sterile water change-out any more simple because I want to simplify my process, and it was extra effort. I recently cleaned out my yeast storage fridge from old jars that were 9-15 months old and noticed that those jars stored under beer smelled much worse (lysed yeast smell) than those that were well-rinsed and stored under sterile water. I highly suspect this was due to the co2 and pressure the cells were stored under for that long of time. I tasted all of the jars (nasty-smelling or not) and the smellier the jar the worse the taste (none of what I tasted was actually swallowed though). I found this sampling very interesting. I leads me to believe that if I was going for short-term storage, say 0-4 weeks, then storing under beer is easy and safe; however, if I'm going for longer-term storage (2-6 months) then rinsing the yeast and storing under sterile water might prove more successful as long as you keep things extremely sanitary. I have since switched to freezing yeast for long term storage and have been very pleased with the results - no failures yet but they do take a extra 1-3 days to come back from freezing when spinning on the stirplate.

Hope someone finds this informational because my wife certainly doesn't :p
 
I love the yeast threads here. I get so many great ideas from them.

After making my first starter with my self made stir plate for my brown ale, I found it to be a great success. This is because my yeast was past its expiration date. That sucker was off and running in less than 12 hours.

Again after reading several threads here about yeast I was thinking about using the freezing approach. Now there is a strong possibility that using multiple mason jars and a large starter might be the way to go. Since I have a dedicated refrigerator that once upon a time was used as a one tap keezer, I am now considering using it as a yeast bank and for lagering. Maybe, I will just use of for a yeast bank now, because I don’t lager anyway (although I would like to try someday). It’s just not my kind of beer.
My thinking is that it should be below the recommended fermentation temperatures for that particular yeast strain. If so then it the future (if so inclined) this would not pose a risk to any particular batch of lager. Of course I could see me filling the whole fridge with yeast,,,,who knows? So having said that, my question is at what temperatures are optimal for storing yeast?
 

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