Bottle Bombs

[John MacKinnon]

Had my first ever bottle bombs after 20 odd brews. It was a stout that finished early in fermentation, cannot remember numbers. I , as I found out, stupidly calculated the sugar to add based on the expected FG....result, a messy fridge. No bottles exploded though, but dressed as a character from the hurt locker to clear it out. Guess the CO2 sugar woke up the yeast and it set to work again on the wort!

 

[John MacKinnon]

Is there a calc to take into account low FG when calculating co2 sugar?

 

[Slid]

Is there a calc to take into account low FG when calculating co2 sugar?

Not that this is a silly question - it is a recurring one for all brewers.
However, the simple answer is just - NO!

This is in the sense that beer will continue to ferment, if in contact with its yeast, as long as there are still some sugars left.
It continues in a fridge at 3C (a bit slowly) and more so in a garage at 10C.

Best advice I can offer is never bottle a beer at a high finishing gravity. What a "high finishing gravity" is, may be part numbers and part recipe and yeast.

Perhaps best to address on a brew by brew basis as some are done at 1.020 and some at 1.002.

 

[dad_of_jon]

I always do one plastic bottle per batch as a carbonation tester. once the bottle is hard it's done, if it goes uber hard chill and protect immediately :tinhat:. a builders trug with an old jumper slung over it will keeps things reasonably mess free and safe if a bottler goes off. - I've had a couple of cracked bottles, of the same type - cant of been designed to hold higher carbed beer, bottled conditioned or wheat beer bottles are stronger. as slid says it depends on the recipe, bottling a beer at 1.020 using mj's saison yeast would be more risky than some other yeasts because the saison yeast is a high attenuator.

 

[Nicks90]

Benefits of using pet bottles is you don't end up with a bomb.
However you will still end up with an impressive gusher.
My cranberry TC is a bit "lively" - after opening a bottle I got 1/4 pint after it had finished spraying my entire kitchens........
I'm now releasing a bit of pressure everytime I go in the cellar. Hoping in a few weeks it'll be sensible enough to try opening without wearing most of it.

 

[ITMA]

Timely thread this. I had a batch which just would not carb. Totally flat even after weeks of testing. In the end I forgot about the batch, left a crate in the loft. I rediscovered yesterday, probably about 3 months old and cracked a bottle open last night.

Mount Etna all over the place.

I've had a previous batch which was a bit lively, but this was clearly a new ball game. So just now I decided to let the gas out of every single bottle. One of them was particularly violent, the force of the cap blowing off pushed my bottle holding hand back a foot or so. Must have been close to exploding.

I guess this resulted in about 3-4 pints of ullage from the batch of 20pts.

I've recapped them and will see if they're in any way drinkable. More as an experiment than anything else. I'm not expecting the batch to be savable, and it wasn't nice anyway.

Lessons have been learned...

 

[John MacKinnon]

Perhaps adding some simple sugars to a stuck ferment in FV may be a way to kick start things. If it worked in the bottle, should work in the FV?

 

[BeerisGOD]

I would still bottle a batch with a high fv with pet bottles but not now I use glass as well .
I think as long as you try your best to get the dormant yeast up again and at a warmer temp then a second reading after a few days should be the 'FV' rather than an 'SG'

 

[John MacKinnon]

Bit of sucrose.... bit of a warmer bath might just rouse the lazy beasties.

 

[BeerisGOD]

Don't talk to me about baths
Ive ruined my temp strips on the FV!
I rely on these like a whore to a curb crawler

 

[GerritT]

I had a 1 gallon batch of gusher that I fed to the garden (sounded a good thing to do), an since the kitchen ceiling incident I'm quite strict in my FG. If it's too high, I add a dash of champagne yeast and wait another week to see if it's the same Brix 3 days in a row.

 

[eltei]

I have a similar problem with a batch of Wilko cab sav wine I made for the good lady. Made dozens of times before so really shocked when it shot out of the bottle like a shook up can of tizer. Had clearly finished fermenting (not sweet to taste) hydrometer reading steady, put stabiliser in, left to clear with finings swilling dj to get rid of co2. Bottled as per usual, left for a fortnight, invited family round and soaked the wife opening the first bottle. Since then 2 bottles have exploded and rest are in quarantine in a wooden box under the stairs. At a complete loss as to what went wrong.

 

[BeardedMag]

I honestly think this is the best thread I've read as I reminisce of one of mine and @Manxnorton rogue bottles blasting across my mother in laws caravan like summit out of a war film resulting in wor lass doing her best impression of summit out of jurassic park.

Great read

 

[eltei]

Think I’m going to empty them into a brewing bucket (good luck there!) make a batch of turbo cider and mix them together to make a “summer fruits cider”.....no carbonation required!

 

[John MacKinnon]

BeardedMag....if you had filmed that you would be a Youtube millionare!

 

[BeardedMag]

Oh I wish!

 

[ukphiltr7]

This is very interesting to read. As yet I have not had any bottles go off, but in saying that I have not had any highly carbinated end products. My last batch resulted in the pet bottles going very hard, but no bonbs.