PSA: Please stop carbonating in growlers

[daksin]

Just an FYI- I've been an advocate of NOT bottling in anything other than bottles for a long time, but I had an interesting experience lately that made me want to remind everyone.

We store our harvested yeast from the 3bbl fermenters in glass growlers, the standard screw top variety. Anyway, the more they sat, the more we noticed that trapped CO2 was escaping from the slurry (foaming/popping when opened for a repitch). This particular growler of slurry had been in the yeast fridge for about a month (longer than we like to leave slurry under beer).

Anyway, we got back from a family event and noticed the place smelled like beer. Not good. Upon inspection, a small river of beer was flowing gently from the fridge. Opening the fridge confirmed what we had feared- one of the growlers had let go. I wish I had pictures, but we spent the next two hours cleaning up so there wasn't much time for a photo op.

There was (still is) glass EMBEDDED in the walls of the fridge, and the force from the explosion had taken out another growler of yeast, two bottles of beer and several mason jars with washed homebrew pitches. If anyone has ever seen a growler let go, you would know that had anybody been handling the growler, they would have certainly been seriously injured, and honestly I think someone could have been killed by this bomb. The force that it threw the big hunks of glass was really scary. I'm considering throwing out the freezer because I'm not sure I can get all of the tiny, paper thin shards out of the walls and nooks/crannies.

In any event, we weren't even CARBONATING in these growlers, and they exploded with some seriously violent force. One thing that surprised me was how EXTREMELY inconsistent the thickness of the glass in a standard growler is. Wall thickness ranged from over a quarter inch to probably around a sixteenth of an inch, just on the sides of the growler. These things are NOT DESIGNED TO HOLD PRESSURE.

Anyway, nobody was hurt and the bottle of Westvleteren 12 I had right next to the growler that exploded survived unharmed, albeit with a smudgy label. Please be safe y'all.

tl;dr Was storing harvested yeast in growlers, they exploded in spectacular fashion, could have seriously injured someone

 

[bierandbikes]

Not saving yeast in growlers, but I washed yeast and saved in mason jars recently. After washing and filling the final jars I screwed the lids on tight and put them in the fridge. Do I need to crack them open to release pressure? They are under water, not beer, so hopefull I am not setting up a bomb in the family fridge.

 

[krackin]

If the mason jar lids flexes when you push on it lightly you are good, if it is hard then you have pressure.

 

[johngaltsmotor]

That's why the yeast vials I use have a cap with a hole in the top and a rubber gasket - pressure makes the gasket bow outward so it doesn't get high enough to jeopardize the glass.
I've never seen a bottle bomb but I don't care to, that's why I store everything in kegs. :-D

 

[trboyden]

Why not use a standard screw top and bubbler (such as used in 1 gallon equipment kits) in place of the screw cap? Allows the CO2 to escape and keeps the nasties out of your yeast. No more bottle bomb potential.

As for carbonating in growlers, I've never had an issue. But I only buy high quality growlers designed for beer and adhere to the recommended dosing for fizz drops. I also don't carbonate for long term storage. If I carbonate a growler, it will be drunk in two weeks or less.

That said, your experience does lead to something that should be a common practice for potentially explosive objects - make sure you store them in a container that can contain the explosion and the resulting mess, just like you would for gas tanks. Thick-walled Polypropylene containers are a good choice because the material has good fatigue properties that would absorb the impact of fragments.

All that said, there is a reason the soda industry uses plastic bottles and aluminum cans for highly carbonated beverages... Package weight during transportation is only one...

Just an FYI- I've been an advocate of...

 

[hexmonkey]

Anyway, nobody was hurt and the bottle of Westvleteren 12 I had right next to the growler that exploded survived unharmed, albeit with a smudgy label. Please be safe y'all.

When did Westvleteren start labeling their bottles? I thought all they had was a different cap for each style...

 

[daksin]

Not saving yeast in growlers, but I washed yeast and saved in mason jars recently. After washing and filling the final jars I screwed the lids on tight and put them in the fridge. Do I need to crack them open to release pressure? They are under water, not beer, so hopefull I am not setting up a bomb in the family fridge.

Washing yeast should pretty much get rid of any trapped CO2. I'd say you're fine.

 

[PoorInRain]

The Westy 12 that I have has a label that is emblazed on the bottle. A bottle bomb of this magnitude would certainly scuff it.

 

[bknifefight]

I dont see the need to stop using growlers, just a need to use an airlock.

 

[Misplaced_Canuck]

We store our harvested yeast from the 3bbl fermenters in glass growlers, the standard screw top variety. Anyway, the more they sat, the more we noticed that trapped CO2 was escaping from the slurry (foaming/popping when opened for a repitch). This particular growler of slurry had been in the yeast fridge for about a month (longer than we like to leave slurry under beer).

This sounds more like you had an incomplete fermentation in the 3bbl fermenter, or that the yeast was harvested too early - not so much a glass container issue.

This incident would just as likely have happened in a beer bottle, if that's what you had used.

MC

 

[Nightshade]

I too store yeast in glass containers from a 3bbl system, but I do not put a solid lid on them and would never consider that to be a safe or reasonable practice...and I brew an average of once a week or better with single and double batches.

What I would consider is using growlers with a couple layers of plastic wrap over the opening held on by rubber bands and extra plastic left for co2 expansion. Having yeast in a solid sealed container even in a cooler (fridge) is unthinkable in my mind.

Glad you weren't hurt and all you lost was yeast but seriously think about the properties of what you are storing and how it functions as an organism.

 

[Grannyknot]

Wow, that's a crazy story.
I can't even get a screw top growler to hold enough pressure to carbonate. Much less hold enough pressure to explode. Seems to just escape right through the threads.

 

[VaBrewer]

Yeah, I had a similar explosion. Thankfully no one was around when it blew. I am still finding pieces of the growler months later.

 

[daksin]

This sounds more like you had an incomplete fermentation in the 3bbl fermenter, or that the yeast was harvested too early - not so much a glass container issue.

This incident would just as likely have happened in a beer bottle, if that's what you had used.

MC

The beers were definitely done, and they wouldn't have been refermenting in the fridge. You can actually see CO2 evolving when we harvest our yeast, but we generally leave foil on for a while before we cap them off to let most of it out (we thought).

 

[daksin]

When did Westvleteren start labeling their bottles? I thought all they had was a different cap for each style...

Mine was one from the US release, it has a gold painted label on the front and a paper label on the back with the US req'd warnings and stuff.

 

[Phunhog]

I was reading somewhere that you don't want to put a tight lid on your yeast for two reasons....1. For the potential safety hazards of exploding glass 2. Yeast don't do well under pressure. I would imagine that if you had enough pressure to explode a growler the health of the yeast would be suspect. Now I still store my yeast in mason jars but I just barely engage the threads and cover with foil. Bacteria and wild yeast don't crawl so it should be fine.

 

[jrgtr42]

I used to bottle my homebrew into growlers.
Out of the couple dozen batches, probably 50 fills into growlers, I only ever lost one, a hefewiezen that I realized was in a bottle (growler) that really wasn;t designed for that - the glass was far thinner than any of my others. It also didn't explode into shards like that, it just went in almost a perfect circle around the circumference. Just a pain cleaning up sticky beer in the morning before going to work.

 

[daksin]

Just wanted to let folks know that because the growlers aren't designed for pressure, the wall thickness can vary hugely. As I said, some growlers from a prominent supplier varied by over a quarter inch in wall thickness.

 

[elkshadow]

Anytime I store yeast, no matter what vessel, I put a sanitized paint strainer bag between the vessel and the lid. Sounds like you learned your lesson.

 

[Billy-Klubb]

back in the early '60s, my granny & grandpa had a similar experience with cider jugs. grandpa bottled too soon & added too much priming sugar. that an cider jugs not being made for pressure made for a bunch of 1 gallon bottle bombs.