Amazing vanishing beer

[Buzz669]

Hi all, just thought I’d share an experience and see if anything similar has happened to other members.
I bottled Triple Tykes Export back in mid May and, along with various other beers, have been slowly working through the 46 odd bottles. I used 500ml PET bottles for this brew.
Yesterday I noticed that the box holding the last bottles had mould growing around the bottom and, fearing a blown bottle, had a cautious look inside .... 10 bottles looking like they were at max pressure and 5 sealed but very empty bottles.
Bear in mind that out here in Spain even the cellar is about 27c at the moment.
Brought bottles into house and into a sink of cold water and ice to reduce pressure and opened the “empties” ... a good satisfying hiss as pressure released and the heady aroma of export with absolutely no liquid!
So bottles not damaged/burst and can only assume that beer has been slowly forced past screw cap. Bottles stored upright and caps still tight!
Remaining full bottles are, indeed, overpressured but the beer is great and the bottles are now living in the fridge (and will be consumed as a matter of urgency ... ahem).
Glad I didn’t use glass bottles on this occasion but wondered, has anyone else experienced this phenomena?

 

[GerritT]

One would guess that there would be at least SOMETHING liquid left in those bottles!

Obligatory question: do the neighbours have children and how old are they?

 

[Buzz669]

One would guess that there would be at least SOMETHING liquid left in those bottles!

Obligatory question: do the neighbours have children and how old are they?

Honestly, nothing but gas ... drinking one of the full ones now though!
As for kids, beer is in locked cellar and no other beer affected.
Mind you, top tip for thieving kids (as happened to me many years ago) bottle some flavoured water mixed with Epsom salts... they nicked it and drank it and had their systems cleaned out. Police came to visit me as there was concern they had been poisoned ... but coppers saw the funny side and said kids never nicked my home brew again!

 

[cushyno]

I wonder if there has been enough pressure to create microscopic splits in the PET bottles or some other manufacturing flaw that would allow liquid out through the material? It would explain the mould. If they were glass bottles I bet they would have exploded or blown the tops off.

 

[Slid]

I wonder if there has been enough pressure to create microscopic splits in the PET bottles or some other manufacturing flaw that would allow liquid out through the material? It would explain the mould. If they were glass bottles I bet they would have exploded or blown the tops off.

PET bottles are pretty much indestructible (hence Blue Planet 2) and would distort before splitting in any number, unless there were some fundamental issue.

Here is a possible scenario - a few years ago, just as I got back into HB - so late 2013, there was an issue with the Coopers 500ml bottles production line. There were, it seems, five "lines" and on one of them, there were tiny holes in the bottom of the bottles. So every fifth bottle leaked like a sieve from the moment bottled.
Coopers were fantastic at providing replacements, but something like this is a possibility?

 

[Linalmeemow]

The very first time I was involved in homebrewing was back in uni in 1995. Some godawful lager kit that we bottled in 2 litre pop bottles and stuck under the stairs to carb up. Went in there a week later and there was a fine mist of beer - the pressure had got too high for the bottles and micro-holes had formed so the beer was spraying out. I suppose it could be the same thing for you, but I'd have expected there to be some liquid left behind, and for the pressure in the bottles to be gone (unless the holes resealed themselves when the pressure dropped to safe levels for the bottles).

When we tried to move the bottles they exploded, fortunately we'd already got them in the back yard. Found a couple of them in the road out the front of the house - they really went off with a bang.

 

[Nicks90]

My daughter has persuaded me to do a bottle bomb on purpose. Mainly because she helps me measure out priming sugar and I keep telling her how important a job it is.
So the last bitter kit has got one PET bottle with 4 heaped teaspoons of sugar in it.

It's sat outside waiting to go bang. But you can guarantee it'll go off when my camera is having its battery charger or over night when it can't pick it up

 

[Slid]

A 500ml PET bottle with 4 teaspoons of sugar will be a gusher. It won't go "bang" unless a stray firework hits it on November the fifth.

 

[Buzz669]

Thanks for the input folks. I’m using Coopers 500ml bottles so it could be the microscopic holes.
Will mark the bottles affected and see what happens if/when I reuse them.
All my years in physics and engineering I’ve seen nothing like it.

 

[Nicks90]

A 500ml PET bottle with 4 teaspoons of sugar will be a gusher. It won't go "bang" unless a stray firework hits it on November the fifth.

Damn.
Might have to help it along then and shoot the thing in a controlled explosion for the enjoyment of girl child

 

[Llamaman]

Thanks for the input folks. I’m using Coopers 500ml bottles so it could be the microscopic holes.
Will mark the bottles affected and see what happens if/when I reuse them.
All my years in physics and engineering I’ve seen nothing like it.

I’d be tempted just to chuck the bottles. The risk of wasting further beer would put me off.

 

[simon12]

This sounds really weird have there been any UFO sighting in the area.

 

[Duxuk]

I gave up on PET bottles years ago because they would get microscopic holes in them leading to the situation you describe. They were Coopers bottles, not recycled pop bottles. Get into glass. It's reliable and infinitely reusable.

 

[Covrich]

You could attached a PET with 4 teaspoons in to the bottom of your feet loosen them and break the speed limit.

I had one bottle which did this well sort of it was glass and I caught it happening had a hairline crack and it just leaking away.

 

[Buzz669]

Well, I think we have the answer in tiny holes, it’s all it can be other than the supernatural (I may come back as a homebrew drinking ghost myself).
The reason I use plastic bottles (a recent idea for me) is that I worry about using glass in the heat out here and not being able to keep the brew cool during secondary fermentation. Didn’t want to risk a glass blow out!
I will reuse these particular bottles just to see what happens .... I know, a potential waste of good beer but .... I’m an engineer ... I can’t just throw them away and not know for definite!
On the plus side, if I see a similar effect again, I can salvage and drink the beer immediately.... and all in the name of science.
Thanks for the input folks.

 

[RichK]

I've also had a couple of PET bottles (half) empty themselves & leave the contents in the bottom of the crate. Whether that was through over-priming & the cap not being on properly I have no idea (the rest of the couple of batches involved were fine & they were batch primed). As I've moved on to glass (with just a single PET bottle from each batch to check carbonation) I just ditched the errant ones.

 

[stan.distortion]

Well, I think we have the answer in tiny holes, it’s all it can be other than the supernatural (I may come back as a homebrew drinking ghost myself).
The reason I use plastic bottles (a recent idea for me) is that I worry about using glass in the heat out here and not being able to keep the brew cool during secondary fermentation. Didn’t want to risk a glass blow out!
I will reuse these particular bottles just to see what happens .... I know, a potential waste of good beer but .... I’m an engineer ... I can’t just throw them away and not know for definite!
On the plus side, if I see a similar effect again, I can salvage and drink the beer immediately.... and all in the name of science.
Thanks for the input folks.

How about filling 'em full of bad beer and giving them a good shake? Or maybe fizzy pop, not sure the pressure would be as high though. Could be worth brewing up a batch of over carbonated sugary water so no good beer is harmed in the experiment.