Bottle bother!

[Appleyard]

Oh, no! I bottled some cider from garden apples, into 23 empty, clean 2L PET bottles, which used to contain "Crofters" cider.

I put 2 (measuring) teaspoons of sugar in each bottle, wanting a slight sparkle but not a huge fizz.

The bottles stood for a few days on some boards on top of the kitchen range, where it's nice and warm, and became very firm.

I moved the bottles into a cool room (~15C) a few days ago, and just now thought I'd better check in case of possible impending bursts.

All the bottles are now rather floppy, and the sides can be pressed in much more easily. As if the contents are flat.

Argh! What's happened? What to do, if anything? Help!

 

[yrhendystu]

Can't speak for cider but I use 2L plastic for my beers and lager kits. 2 teaspoons will be fine for a little bit of a fizz. It might just need to be left for a bit longer. I'd aim for 2 weeks.

I wouldn't worry about it bursting. I usually prime with around 2 tablespoons of sugar and never had an issue.

 

[Appleyard]

I'll do that. What worries nme is that they were all firm and tight and pressureised before I moved them into a cooler place. Now they are distinctly underinflated. I am tempted to think "leaky caps", but surely not on ALL bottles, which is the case now. I tightened the lids by hand, fairly firmly, but not as tight as possible, and did not touch them between when the bottles were "tight" and now, so if the seal was faulty I would not expect initial pressurisation. I have no idea what's happened, but something has.

I don't want them to start to spoil. I have in the past had problems with film yeast on top of cider stored in 2L glass jug type jars, which was awful.

 

[AXW123]

I would put them back in the warm for a couple of weeks. It’s unlikely they are leaking. Co2 is created initially and if there is some pressure it will then absorb into the liquid and the longer you leave it warm the longer it will ferment. 2tspns will give a gentle fizz if you want more go up to a teaspoon per 500ml.

 

[An Ankoù]

My cider takes ages to condition. It's usually ready in time for Easter.

 

[terrym]

Can't speak for cider but I use 2L plastic for my beers and lager kits. 2 teaspoons will be fine for a little bit of a fizz. It might just need to be left for a bit longer. I'd aim for 2 weeks.

I wouldn't worry about it bursting. I usually prime with around 2 tablespoons of sugar and never had an issue.

Do you really mean tablespoons. 1 UK tablespoon is 3 UK teaspoons and if you are priming at about 1 tablespoon per litre that will give you a CO2 content of well over 4 volumes which is out of the range of all but wheat beers.

I'll do that. What worries nme is that they were all firm and tight and pressurised before I moved them into a cooler place. Now they are distinctly underinflated. I am tempted to think "leaky caps", but surely not on ALL bottles, which is the case now.

I use mostly PET bottles of various sizes. I re-use bottles several times and don't use excessive pressure on the caps. However in nearly six years of brewing beer since I returned to the hobby and brewing over 2000 litres of beer which has gone into PET bottles I have never had a PET bottle leak or lose pressure. So based on my experience you are unlikely to have one let alone all your bottle lose pressure. What you have experienced is normal. PET bottles can be appear pressurised when the beer is at room temperature, but move them into a cold place and the bottles go less tight. Its all down to the CO2 in the headspace being able to be absorbed as the beer gets colder thereby reducing the pressure within the bottle. And the warmer and then colder the beer the more noticeable the difference.

 

[Appleyard]

Oh arr. THAT is very interesting. An experiment should be made, I feel. I will get a sample of bottles out of the sitting-room, and put them back on top of the range, and see what happens!

EDIT: What effect will having the cider "cool" be? Will it lose fizz, or will the CO2 bubble as normal? Any idea?

 

[terrym]

Oh arr. THAT is very interesting. An experiment should be made, I feel. I will get a sample of bottles out of the sitting-room, and put them back on top of the range, and see what happens!

EDIT: What effect will having the cider "cool" be? Will it lose fizz, or will the CO2 bubble as normal? Any idea?

All that happens with any carbonated drink with a given amount of dissolved CO2 within it is the colder it gets the less likely it is to give up its dissolved CO2. Conversely if you warm it up (in an open environment) the CO2 will bubble out of solution since the equilibrium point has been changed. So if you like your cider or beer served chilled it you might consider adding a tad more sugar relative to serving it warm.

 

[yrhendystu]

Do you really mean tablespoons. 1 UK tablespoon is 3 UK teaspoons and if you are priming at about 1 tablespoon per litre that will give you a CO2 content of well over 4 volumes which is out of the range of all but wheat beers.

Yes but I don't actually fill the bottles all the way. It's more like 1.7L and then I squeeze the air out. So I guess some of the CO2 is 'wasted'.

 

[Appleyard]

All that happens with any carbonated drink with a given amount of dissolved CO2 within it is the colder it gets the less likely it is to give up its dissolved CO2. Conversely if you warm it up (in an open environment) the CO2 will bubble out of solution since the equilibrium point has been changed. So if you like your cider or beer served chilled it you might consider adding a tad more sugar relative to serving it warm.

Thanks, that is interesting. I won't be having it, or serving it, if it's chilled - probably just "cool". I will bear in mind about the sugar. Having exploded bottles in the past, I am rather chary about adding too much sugar.

 

[Appleyard]

Yes but I don't actually fill the bottles all the way. It's more like 1.7L and then I squeeze the air out. So I guess some of the CO2 is 'wasted'.

Oh! That's interesting too! I've got air on top of my cider now, I guess, but CO2 would be much better. I can't squeeze glass bottles, ofc, but I had thought of letting a bit of air out to emulate what you do to get CO2 on top. Yours is a much better idea, I like it. I have not used plastic bottles before, so hadn't thought of that (durr... ). Thanks!

 

[terrym]

Yes but I don't actually fill the bottles all the way. It's more like 1.7L and then I squeeze the air out. So I guess some of the CO2 is 'wasted'.

I am interested to know why you only part fill your bottles. I also use PET but almost fill them and like you squeeze the air out. However you appear to use 3 times the amount of sugar I use. And my carbing levels are fine.

 

[Appleyard]

I am interested to know why you only part fill your bottles. I also use PET but almost fill them and like you squeeze the air out. However you appear to use 3 times the amount of sugar I use. And my carbing levels are fine.

Am I leaving enough space at the top of my bottles (the three in the foreground which are cider)?

 

[terrym]

Am I leaving enough space at the top of my bottles (the three in the foreground which are cider)?

I fill my bottles to 20-25mm from the top, squeeze the air out and when they are fully carbed they will end a little below that.

 

[yrhendystu]

I am interested to know why you only part fill your bottles. I also use PET but almost fill them and like you squeeze the air out. However you appear to use 3 times the amount of sugar I use. And my carbing levels are fine.

When I first started I read to leave a gap at the top but that was small bottles so I likely just scaled it up. Maybe wrongly but I just stuck with it. Plus 1.7L is pretty much 3 pints so easier to measure consumption too.

 

[Appleyard]

Result: I took a sample of three bottles, and stood them over the range. They have firmed up nicely. Indeed, there is evidence of action, in the form of a tiny string of bubbles from one point on the bottle bottom of two of them.

I will keep an eye on them, and if they become worryingly tight, I will let a bit of gas out[1]!




[1] NO! Out of the *bottles*!