Exploding Swing Tops

[tezcatlipoca]

Hey guys,

I come to you today with a very important question: have you ever had an unopened swing top liter bottle of beer/homebrew explode?

I must ask this as one of mine just did this. No one was hurt thankfully. I bought these cool looking cobalt blue 1 Liters and have rarely use them. Purchased them recently. This has never happened with my brown ones, so I am thinking I have a bad batch or bottles not rated to hold pressurized beer. At this point in time, it isn't worth risking so I'll be smashing and trashing the pretty blue ones. Now, should I keep my brown.

I bottle a lot of beer and pay loads of attention to sanitization, so I doubt these are infected bottles. I also bottle a few 1 Liter and then generally a case of regulars. These regulars never explode and hardly ever turn out infected. I haven't had an infected bottle in the last 20 batches or an overcarbed bottle. Let me know your thoughts and experience.

Charles

 

[RedlegEd]

The pretty blue ones command a premium price...it's a shame it blew up on you. I only have one or two, and have never had an issue. I'm guessing you had a bad one? There should be nothing inherently worse about blue v brown glass, so I'd suspect a bad bottle, or maybe even something in the bottle that created an overpressure situation. How many do you have? If you have more that are filled, you could maybe put them in a Rubbermaid tote, or some other container that won't leak and will contain flying glass.

 

[tezcatlipoca]

I have 9 of 'em. I have three filled. I'm thinking I'm not even going to move them. I'm just going to quarantine that part of my house off for six months. The shards that came from that one are just too scary to think about. Many large shards made it pretty far. The whole bottom came off in one piece and made it 6 feet...so, that was like a 3-4in diameter glass saucer.

 

[tezcatlipoca]

And yes, they were quite expensive, but no where near the cost of an emergency room visit.

 

[E_Rock]

I think my very first post here several years ago was about some 1L flip tops that exploded on me. In my case, the bottles were quite old that were given to me. On 2/3 of them, the bottom blew off in one piece. The third was fine. I had been keeping them in the basement in Feb, but it seemed too cold, so I moved them to an upstairs bedroom. You know, the bed room that was soon to be the nursery to my 2nd child 8 days later. I of course had them on the rug on top of the 90 year old hardwood floors. My wife took it quite well all in all, even if the nursery smelled like a frat house basement for a few weeks.

I never quite figured out what happened. I had soaked all the other bottles in oxy and at the last minute decided to use these flip tops. I washed them with soap and water. So either they got infected or perhaps had hairline cracks. I tossed the rest of them after that and never used them again.

Best I can recommend is to put them in a rubbermaid bin. Should they explode, at least you can contain the mess.

 

[user 214470]

I have over 80 brown flip-tops (1 liter) and use them since I started homebrewing - some bottles already had over 10 beers in them, and believe me or not - I've never lost one due to explosion, and I haven't even shattered one myself - they're pretty strong.
I guess you might have gotten some bad quality bottles or you've just overdid with priming sugar...

 

[tezcatlipoca]

I bottle from a force-carbonated keg, so I know the pressure cannot get over 10Lbs at the same temp. That being said, I also have never had a brown bottle burst. I'm thinking the case of cobalt blue ones I ordered were just not up to snuff. At this point in time, I think three have busted with at least two different beers in them. I must emphasize that I pay the utmost respect to sanitization of bottles before I transfer. Also, the beer stays in the keg for weeks and it definitely isn't infected. I think I'll quarantine that part of my house for a few weeks and then throw them in a Rubbermaid can...

 

[phug]

The advantage to swing tops that are over carbed is that if you can chill them down, you can just release the pressure several times over the course of a few days and alleviate most of the problem

 

[Grantman1]

Correct me if I'm wrong, but I believe these types of bottles are not technically built to hold the pressure necessary for bottle carbing, despite the fact that they often work out fine.

 

[user 214470]

I think the they are built for that pressure. Beer is sold in them, so I don't see why they wouldn't be strong enough. Here, in local supermarkets, they sell unfiltered/unpasteurized Hefeweizen with lots of yeast and lots of pressure in these brown 1 liter swing top bottles. That's pretty much bottle conditioning..

 

[Grantman1]

I think the they are built for that pressure. Beer is sold in them, so I don't see why they wouldn't be strong enough. Here, in local supermarkets, they sell unfiltered/unpasteurized Hefeweizen with lots of yeast and lots of pressure in these brown 1 liter swing top bottles. That's pretty much bottle conditioning..

Doesn't necessarily mean that they are bottle conditioned, though. They would still have pressure, and a hef will always have lots of visible yeast.

 

[user 214470]

Well, I personally still don't agree with you
Here in Europe these bottles are pretty common, especially in craft breweries, I'm pretty sure many of these bottle condition in them. I'm not sure if the designer of this bottle actually intended it for conditioning, though But it's #1 choice for homebrewers here who bottle - 1liter, almost free when buying with beer, and I actually never heard of bottle bombs from these, unlike the 17oz crown cap ones (which are made from thinner glass btw)...

I guess if you want to be super safe when bottle conditioning - go with Champagne bottles - you can use either bigger crown caps, plastic self fastening corks, or regular corks with wire. I make sparkling wine in them, had pressure gauge hooked up on one, and once I overdid with priming sugar ("dosage") - the pressure reached over 100psi, but didn't blow up. That was scary of course - I immediately (and carefully) popped all of them once I saw that pressure...

 

[wired247]

Hefeweizen is not normally bottle conditioned at the breweries . In many cases the yeast that is in the bottle is not the yeast that was what the beer was fermented with and it is added just prior to bottling for no other reason than often times brewery yeast is bred to floc out too efficiently and the haze you expect with hefeweizen isn't there. At Pyramid ales I'd introduce a fine pasteurized lager yeast addition just before bottling to beer that had been sub micron filtered because that yeast stayed in suspension with minimal floc. .

 

[tezcatlipoca]

Just to reiterate. I don't bottle condition. I bottle already carbed beer from a keg. I haven't had a brown bottle do this, only the blue cobalt ones. I thinking these bottles might not be strong enough. At the very least, they seem weaker than my brown ones. When I get home I might see if I can take some thickness readings of the blue ones and compare against the browns. Would be nice to know if the bottles just can't handle them or if I just got a bad bottle.

 

[IslandLizard]

Sad to hear you lost a nice bottle and the beer in it, then had to clean up all the mess, shards, etc. Be glad no-one got hurt.

Last year at a beer meeting someone opened one of those skinny tall brown flip top containing his Belgian Dubbel, and the emerging pop was unbelievably loud, like old fashioned soda. That bottle must have been very strong!

Have you considered that the beer may not have been fermented out when you bottled?

 

[Chaotic_Goodness]

Just to reiterate. I don't bottle condition. I bottle already carbed beer from a keg. I haven't had a brown bottle do this, only the blue cobalt ones. I thinking these bottles might not be strong enough. At the very least, they seem weaker than my brown ones. When I get home I might see if I can take some thickness readings of the blue ones and compare against the browns. Would be nice to know if the bottles just can't handle them or if I just got a bad bottle.

Yeah, I've learned to be careful with the 1L size swing tops. Some are not manufactured to hold carbonated beverages, but fancy flavored oils and vinegars. Measuring the thickness is a pretty good indicator, but I usually compare by weight. An EZ-Cap weighs noticeably more than a light-duty bottle.

 

[tezcatlipoca]

OK, so I measured the thickness of the exploded bottle to be between 0.12 to 0.14 inches depending on the spot. What do you make of that guys? What's the typical thickness?

I'm pretty certain it fermented all the way out. This was my Grodziskie, so it had a FG of 1.014, which is what I aimed for. It is possible that a couple bottles picked up an infection, but I do pay close attention to sanitization. I am thinking it is more likely I have a case of decorative bottles not meant to hold any pressure. If this is the case, I need to know as I have several filled blue bottles left. I appreciate all y'alls help in getting to the bottom of this.

In the meantime, I think I'll weigh 1 brown bottle against 1 blue bottle and see what that tells me.

 

[tezcatlipoca]

With swing tops on, the blue bottle weighs 727 grams, the brown weighs 733 grams.

Without swing tops, the blue weighs 706 grams and the brown weighs 712 grams.

This leads me to believe that this was solely caused by some kind of over pressurization, despite only blue bottles suffering. It is possible though to have an infection and the high FG would mean an infection would have driven the pressure up even higher. So, I guess I need to pay even more attention to sanitization..?

I think my browns are EZ-Caps, just FYI.

 

[z-bob]

Wearing leather gloves, jeans, long sleeved heavy shirt, and a full face shield (I have that stuff anyway) I would transfer the unopened bottles to a fridge. Or a Rubbermaid tote and cover with ice. Once they are nice and cold, they should be safe to open.

 

[wallenda]

I had a bunch of bail type bottles and didn't really use them but found that Kambuchi brewers really like them and are willing to pay a decent price for them. Apparently during their fermenting process they need to "burp" the bottles and these work best for them. So don't throw them away put them on Craig's list and sell them or pass them on.

 

[tezcatlipoca]

Wearing leather gloves, jeans, long sleeved heavy shirt, and a full face shield (I have that stuff anyway) I would transfer the unopened bottles to a fridge. Or a Rubbermaid tote and cover with ice. Once they are nice and cold, they should be safe to open.

I basically did this last night. Carhartt jacket, jeans, full face helmet, deer skin gloves. Opened them all up on the shelf, then transferred to a container. Everything happened pretty safely. Nothing exploded. I measured the gravities of the beers. Most were 1.010 with a few being above that. Of course, I had to pour between glasses to get the carbonation out.

 

[ncbrewer]

Bottling at 1.014, and going to 1.010 in the bottles would explain the over-pressure.

 

[tezcatlipoca]

The 1.014 was in the keg. It sat in the keg for at least another few weeks before I bottled.

I'm starting to wonder if the temperature is a factor. Someone correct me if I'm wrong. I'm bottling beer at 33 degrees around 2.2 volumes of co2. If I warmed this beer up to 70 degrees, the pressure would increase in the bottle, forcing the beer to carbonate even further. I do store some at this temp, but I always cool back down before I drink them. Last night, I opened them at this temp. Would the pressure and volumes of CO2 be a lot higher at 70 degrees? I am thinking some of my bottles were infected: maybe 2/8. One read a pretty low FG when I measure from the bottle. The other suspected one would be the one that exploded. Thoughts now?

 

[ncbrewer]

"One read a pretty low FG when I measure from the bottle." Were others higher? I'd say different gravity in the bottles points to an infection in some of the bottles. It could be a little crud that you missed when cleaning, or maybe fruit flies got into some - I'm seeing way more of these than previous years.

 

[tezcatlipoca]

"One read a pretty low FG when I measure from the bottle." Were others higher? I'd say different gravity in the bottles points to an infection in some of the bottles. It could be a little crud that you missed when cleaning, or maybe fruit flies got into some - I'm seeing way more of these than previous years.

I should say they were different brews. American porters were 1.010. American amber was 1.006. It's six months old. Rauchbier was very low at 1.002 and I think the one that exploded was a Rauchbier but it really is impossible to tell. 3 Amber's, 2 porters, and 1 rauchbier and the mystery explosion.

I am really thinking that my rauchbier got infected and that is what lead me here. Maybe I was lax that bottling day. If I had to blame anything I would say not clean enough beer gun, though I haven't infected bottles since the rauchbier.

I would say this is a case closed. I am still interesting in changes of pressure on non-infected bottles. Can't help but think if I kept the 1 liters in the fridge, I wouldn't even know about this potential to explode.

 

[Chaotic_Goodness]

Yes, temperature is definitely a factor. Google "Ideal Gas Law." pV=nRT (pressure)(Volume) = (number of moles)(Gas Constant)(Temperature), so a large rise in temperature can significantly increase the volume required to maintain a particular pressure. More CO2 will stay dissolved in the beer at lower temperatures, so warming the beer up doesn't add more carbonation to the final product, but does increase your chances of bottle bombs.
As far as your Rauchbier being infected, does it taste/smell off? What method of pasteurization did you use?

 

[tezcatlipoca]

I know of the ideal gas law, but it only applies to gasses-->my chemistry teacher would be so proud! So, I did a little experiment very recently with bottles of my Belgian golden strong ale. One at 33, one around 55, and one around 72. While the warmer one had more of a pfft when I popped the top and it was more carbonated, it wasn't drastically different. When poured, the warmest one had a head of maybe 1/8" bigger than the coldest. Warmest one was still not over carbonated to me, though I couldn't finish all of it warm.

Rauchbier tastes infected? Gosh, this is a really hard one for me to tell. There is a subtle twanginess but not much overpowers smoke flavor for myself. I don't pasteurize as I very rarely get infections. That being said, after the different bottle tests, I'm thinking the rauchbier had to be infected. Bummer.

 

[z-bob]

I would say this is a case closed. I am still interesting in changes of pressure on non-infected bottles. Can't help but think if I kept the 1 liters in the fridge, I wouldn't even know about this potential to explode.

I think the main issue is the solubility of CO2 in water as a function of temperature. Gases (I think all of them) are much more soluble in cold water, so less tries to leave solution and pressurize the headspace. And if there's any fermentable sugars left in the beer, the cold temperature will slow down the yeast so the pressure doesn't rise as fast.