Exploding Bottles

[ChazMan]

If i am to encounter exploding bottles, about how far into the 2nd fermentation could i expect this to happen?

I'm using Coopers Lager (microbrewery) , PET bottles.

[wambesi]

By 2nd fermentation I gather you mean the bottling stage.
In that case exploding bottles happen for a variety of reasons, two most common are over priming or fermentation not yet complete.

Both will not happen at a certain time or stage but rather when enough CO2 has built up.

[Boonie]

Wont happen with PET, Chazman.

Exploding bottles is fairly uncommon these days and they would be glass.

If you have a Hydrometer, check the brew from the fermenter after 6 days, take note of the reading, check again the next day 24 hours minimum and if it is the same, bottle it.

As stated above, if the ferment is not complete and/or you put too much sugar in the bottles for secondary ferment........kaboom.

PET would just fizz over when you opened, sort of like shaking a bottle of coke and opening immediately.

Cheers

Boonie

[bellboys backyard brew]

Here's a question that goes along with this topic:
How long does everyone let their brews ferment before bottling?

I leave mine go until the airlock stops bubbling. This is usually for about 10 days, sometimes up to 25 days if I'm too busy to bottle. Have been told by homebrew shop, brew is quite safe up to 4 weeks in barrel with airlock. I don't rack my beers at all. As I understand, my glass bottles are in no danger of exploding when bottled at these times. I individually prime each bottle using a level measuring 1/2 or full teaspoon whether stubs or longnecks. I only take gravity readings for alc% calculation.
A mate has found that you can't store homebrew long term in PET as they start to lose fizz longer than 12 months.

(This may not be a problem, am currently shielding my face in preparation for the berating re: not drinking beer fast enough, maybe I should smear myself with AUStealth?)

[KEG]

you've been alright so far, but the ONLY safe way to know when the beer is ready to bottle is to take gravity readings a couple days apart to make sure firstly that it's reached something near the expected final gravity, and secondly that it is stable.

[earle]

but the ONLY safe way to know when the beer is ready to bottle is to take gravity readings a couple days apart

This is true but I don't always take hydro readings. If its a brew that I've done a few times I watch the bubble action that indicates fermentation is taking place and leave in the fermenter for 10-14 days then bottle. The only explosions I've had were my first batch of ginger beer and I figure this was not fully fermented. For this reason when I'm trying a different sort of brew e.g. different types and amounts of fermentables or a different yeast I will use hydro readings.

[Fozzman]

I had 1 random exploding bottle out of a batch probly about 4 months old when i was visiting my cousin. I had left them in the car which got super heated by the brisbane sun and i found the next morning glass everywhere, an all pervading beer smell and a big hole in the ceiling from the cap.
but i believe it was caused by heat.

[ChazMan]

Ok - yeh 2nd fermentation meant that i have bottled it and it is sitting aside in the PET bottles.

I don't think i will have any issues with priming as i used to carbonation drops/lollies - so hopefully they are measured accurately to prevent this..

[rwh]

I never take hydro readings. I just ferment for however long, until it's been stopped bubbling for a day or two, say a total of 7-10 days, then I rack, then I leave for up to another two weeks, then bottle or keg. When you're looking at these timeframes, the risk of incomplete fermentation is almost zero. Of course it helps to have lots of fermenters.

[r.magnay]

Bottles that have not been cleaned properly can cause a further reaction that forms excessive gas as well, I guess you could group that under not fully fermented because the couple of those that I have had in the past, was caused by the yeast setting hard in the bottle, then not being washed out at cleaning time, then when you refill it softens and starts to work again! Usually only causes a mess on opening, but could cause bottles to pop.

[rwh]

In that case it's not actually the yeast that are firing up again, it's the bacteria that the deposit is harbouring. Bacteria have the ability to digest the more dextrinous sugars that are left over after ferementation by yeast. That's what causes the buildup of gas in single bottles if they're not sufficiently clean. For the same reason, the beer will become watery and bitter because the balancing sweetness from the sugars is lost over time as the bacteria digest them.

[Peter Bradshaw]

Put me in the rwh category. I used to check with my hydrometer, but now I simply ferment for 7 days, then rack for a further 7 days before bottling.

Cheers, Pete

[TommyH]

In that case it's not actually the yeast that are firing up again, it's the bacteria that the deposit is harbouring. Bacteria have the ability to digest the more dextrinous sugars that are left over after ferementation by yeast. That's what causes the buildup of gas in single bottles if they're not sufficiently clean. For the same reason, the beer will become watery and bitter because the balancing sweetness from the sugars is lost over time as the bacteria digest them.

I would agree with this. I remember opening a bottle once and froth spewed out the top. On closer inspection I saw a speck of mould on the inside of the bottle.
My question is: Would that mould/bacteria be harmful at all?

[bolwell]

Nah, that mould/bacteria had been swimming in beer for a few weeks and as such was way too drunk to be harmful to anyone except himself.

[warra48]

I leave my brews in the fermenter for 2 weeks. I only rack when it is a lager or pils for lagering, or if the style requires cold conditioning for a period.
I don't always remember to take hydrometer readings. I try to do it now when first into the fermenter, and at bottling, but only to work out the efficiency of my AG brews.

[scanman]

I leave the first fermentation for 2 week minimum usually, mostly because of work and me being to lazy to remember to rack.
If doing any lager I rack and even chuck it in the fridge to help clear the brew ( stuff using fining or anything liek that, I find them not necessary at all )
Ales I just rack for priming and then bottle.
Lagers I try to rack for 3 weeks, depending on how eager I am to try the drop then bottle.
Either way, racking gives you a nice clean looking beer in m opinion. Not so important with Ales I know.

[beerdrinker]

I ferment ales for 5-7days rack 7 days then turn down fridge to 4C for 10 days, ends up nice and clear with minimal crap in bottles