How much infection is too much infection? Swollen Cube.

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kahlerisms

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hello folks

been happily AG brewing and cubing for about three years now (time goes fast!) but I find myself with my first swollen cube.

In November I did a double batch of Janet's Brown into two cubes. When I went to ferment a week or so later I found one of the cubes had swollen right up. I fermented and drank the non swollen one and thought I'd keep an eye on the swollen one as a bit of an experiment to see how it tasted when it was done doing whatever it was doing.

Since that day in late November I have released the pressure on this cube two or three times a week. The cube is pretty round now, it'll never be a cube again. What is interesting though is that the gravity has barely dropped - I kinda expected whatever is producing CO2 in there would've eaten all my sugar by now.

Grav was 1070 when it went in the cube, now it's about 1060 and not moving (though the cube appears to keep swelling).

I want to give whatever this is a crack but I don't want to destroy any other equipment while I'm at it (I'm a plastic bunnings fermenter and Better Bottle kinda guy).

I'm now resigned to the fact I probably have to throw some yeast into this guy to get it to finish out. Does anyone have any thoughts on if whatever is was growing in my cube will also render a plastic fermenter no good? I guess the alternative is to just ferment in the cube (there's heaps of headspace now after four months of swelling). Hmm maybe I've solved my problem just by writing it down.

Anything else I should be aware of or does anyone have any expertise on swollen cubes or other infections to keep in mind?


Cheers
 
[SIZE=12pt]Oh mate, I just love this. [/SIZE]

[SIZE=12pt]There has been a lot of speculation on here regarding swollen cubes. How much did yours swell up before it stopped fermenting? [/SIZE]

[SIZE=12pt]Your cube may still be OK, does it have any stretch marks? [/SIZE]

[SIZE=12pt]I have been using the same cubes as casks and letting the swell for years now.[/SIZE]

[SIZE=12pt]Take a look at this thread. [/SIZE]http://aussiehomebrewer.com/topic/70056-carbingconditioning-in-a-cube-before-keg/

[SIZE=12pt]I don’t suppose you have any pictures do you?[/SIZE]

[SIZE=12pt]Cheers [/SIZE]
[SIZE=12pt]Sean[/SIZE]
 
I would think the fermentor would be fine given that it would be vented via glad wrap or air lock.
 
The cube is pretty round now. I reckon it'll now have a capcity of 26 litres or something. It's huge. I'll post a pic compared to some other cubes tonight.


My concern around the fermenter is permanently infecting it with whatever is producing CO2 in my cube - not blowing up a fermenter :)
 
[SIZE=12pt]Please do post pictures. You could just loosen the cap a little and let it ferment out in the cube. You don’t need to put it in the fermenter and risk transferring an infection.[/SIZE]

[SIZE=12pt]I would be interested in what would happen if it’s left it as it is though and see what happens. [/SIZE]
[SIZE=12pt]Maybe put it somewhere safe and see if the pressure stops it fermenting or if it keeps going till it bursts. [/SIZE]
 
Hi,

If you want to see how it turns out being that it is infected (known)

Why not tip out 2 litres to make some headspace, throw in some packet yeast, convert the lid to have a grommet and blow off hose and let it ferment in that cube?

No need to risk the FV.

B)
 
Have you smelt it?

My experience of swollen cubes is not something I would want to ferment. Personally I'd say goodbye to cube and wort.
 
I agree with the experimental aspect.
Even with infection in a fermentor a good rigorous clean would fix it no.
If not a bunnings fermentor is 20 bucks isn't it?
Or get a bung and airlock and put some yeast in and ferment in the cube and see how she goes.
 
Pratty1 said:
Hi,

If you want to see how it turns out being that it is infected (known)

Why not tip out 2 litres to make some headspace, throw in some packet yeast, convert the lid to have a grommet and blow off hose and let it ferment in that cube?

No need to risk the FV.

B)

If it was mine I would just chuck it.

But if you really want to try, as Pratty1 said, just dump out enough wort to allow fermenting and pitch some yeast into the existing cube. Cover the lid opening with some gladwrap and an elastic band. Then no fermenters etc are used, and the only thing lost is a pack of yeast (or even dump some yeast cake from another batch)
 
Even with infection in a fermentor a good rigorous clean would fix it no.
I've had repeat infections I've narrowed down to a cube or fermenter. Even one repeat has cost more than a replacement in ingredients and time.

Or get a bung and airlock and put some yeast in and ferment in the cube and see how she goes.
No need for bung and airlock - as suggested above - just back the lid off a few turns. Gas will escape.
 
kahlerisms said:
hello folks

been happily AG brewing and cubing for about three years now (time goes fast!) but I find myself with my first swollen cube.

In November I did a double batch of Janet's Brown into two cubes. When I went to ferment a week or so later I found one of the cubes had swollen right up. I fermented and drank the non swollen one and thought I'd keep an eye on the swollen one as a bit of an experiment to see how it tasted when it was done doing whatever it was doing.

Since that day in late November I have released the pressure on this cube two or three times a week. The cube is pretty round now, it'll never be a cube again. What is interesting though is that the gravity has barely dropped - I kinda expected whatever is producing CO2 in there would've eaten all my sugar by now.

Grav was 1070 when it went in the cube, now it's about 1060 and not moving (though the cube appears to keep swelling).

I want to give whatever this is a crack but I don't want to destroy any other equipment while I'm at it (I'm a plastic bunnings fermenter and Better Bottle kinda guy).

I'm now resigned to the fact I probably have to throw some yeast into this guy to get it to finish out. Does anyone have any thoughts on if whatever is was growing in my cube will also render a plastic fermenter no good? I guess the alternative is to just ferment in the cube (there's heaps of headspace now after four months of swelling). Hmm maybe I've solved my problem just by writing it down.

Anything else I should be aware of or does anyone have any expertise on swollen cubes or other infections to keep in mind?


Cheers
ferment it out and put it in all the comps as a specialty :) Or bring some to the next meeting and say it's an English beer :)
 
S.E said:
[SIZE=12pt]Please do post pictures. You could just loosen the cap a little and let it ferment out in the cube. You don’t need to put it in the fermenter and risk transferring an infection.[/SIZE]

[SIZE=12pt]I would be interested in what would happen if it’s left it as it is though and see what happens. [/SIZE]
[SIZE=12pt]Maybe put it somewhere safe and see if the pressure stops it fermenting or if it keeps going till it bursts. [/SIZE]
Waiting was my original intention but we're around month five now - how long would you propose I wait? I'm done waiting, time to make a decision.


It still smells fine though I haven't tasted it. Sounds like I'm on the right track with the ferment-in-cube idea. Might throw a pack or two of US05 in there and come back in a fortnight
 
Update: rehydrated some US05 and threw it in the cube. Took another grav reading before I did. 1052. So in four months, somehting has eaten about 8 gravity points worth of sugar.

Had a taste, tasted pretty normal. Perhaps a very slight rotten fruit aroma/tang like if you leave a few oranges in your fruit bowl too long.

This thread makes me think I maybe should've have bothered
http://aussiehomebrewer.com/topic/80011-cube-swollen/#entry1171463

Oh well.
I'll report back again once we're done.
 
It is in all probability a wild yeast, one that isn't very alcohol tolerant, so its pulled up when the alcohol is only about 1.3%, no surprise there.
I would under no circumstances put it in my fermenter, the bug may be low in alcohol tolerance but it has survived whatever you did to clean/sterilise the cube and the pasteurisation that the wort underwent in the no-chill process so it is a tough little bugger and I very much doubt that you want it taking up residence in your brewery - where you will get to enjoy it again and again...

The cube will continue to stretch while ever there is enough pressure, think of thermoplastics like HDPE as very slow moving liquids, if you keep pushing they will keep moving and as they get bigger they get thinner and it takes less and less pressure to stretch them more and more until the inevitable happens - pop.

Personally I would have tossed the whole lot as soon as I saw the first sign of swelling and the odds that the beer will be good are pretty low, but there is no way to tell, out of the millions of wild yeast strains out there you might have lucked onto one that isn't too bad - the odds that it will taste better than a proper brewing yeast are a lot lower than the odds of winning lotto - but there are lotto millionaires out there so who knows.
Mark
 
If you're doing yourself something as an experiment and in the name of science and don't intend on serving to your best mates or enemies then all good. Just inform yourself of what the possibilities are, how you can measure and verify them etc. No point going off smells and tastes when you don't know.

Do you have any sciencey friends who could test for C.Botuli? Does anyone on here possess such equipment/skills? It could be a way of proving something and contributing further to the knowledge of something which is serious, yet gets undermined with people ignoring the true risks based on anecdotal evidence.
 
Yeah it is an experiment. $4 worth of yeast after $40 of ingredients seems a small contribution in comparison to see how things go.

As per the comments on infecting other equipment, I elected to ferment in the cube for exactly this reason (though the cube is in one of my fermenting fridges)
 
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