Preventing oxidation of Hazy IPA's in Howler/Growler

[Rob2010SS]

I know this has probably been discussed/answered in other threads somewhere. However, my google-ability is not very good and I never know the right words to search for to find what I'm looking for, LOL.

Here's the question I'm trying to answer: Is there something that can be added to a keg that can prevent, or help reduce, oxidation in hazy IPAs when filling howlers/growlers?

Here's the backstory....
We have a group of people that we fill howlers and growlers for whenever we put something new on tap. We bought a bunch of these howlers with our logo on them...

In 2020, we brewed a hazy that we shared with the group. At that point, these howlers were fairly new and we didn't have a lot of experience with them. We were filling them up to the very top of the glass and capping them. We were practically capping them on liquid. The thought process was that if we fill them that full, there's no room for air or oxygen, and if we don't have any oxygen in the howler, the beer should be well protected.

We started having a few of these explode. They would all break here in the circled area below...

Ultimately, after more failures and more breaks, we came to the conclusion that we were overfilling the howlers and the CO2 escaping from the beer was causing them to blow out the bottoms right in that crease in the circled area above. Since we have stopped filling to the top of the glass and only filling to the 1L / 32oz mark on the glass, we have had no blow outs.

Fast forward to 2021, we brewed another hazy and shared with the group. We now filled the howlers to the 1L / 32 oz line and people were drinking them fast enough that the flavor wasn't affected too much, but when we got a couple of pictures of the beer, it was clearly oxidized. It went from bright yellow to that well known dark brown, almost purple, oxidized look. We started sticking a CO2 tube in the neck of the howler when filling to try and flush it out and it helped some of them but not all of them.

We're going to be brewing another hazy here in a couple of months. We want to be able to have people enjoy this the way it was meant to - bright and fresh! I know howlers and bottles are not ideal for hazies, and that's why a lot of people just don't bottle them. I've also seen talk of adding different ingredients at time of kegging to help prevent oxidation and improve shelf stability.

What are my options here as far as additions that can be added to the keg to possibly help reduce this - if there are any options at that?
- I know those K-Meta and Na-Meta ingredients are antioxidants but not sure if those can be added to fermented, carbonated beer without affecting flavor.
- Can they just be added to the howler or do you add them to the keg?

As far as how we brew these, we're not doing LODO by any means, but once the beer is in the fermenter, it doesn't see oxygen again. We ferment in a unitank, we're dry hopping after fermentation is complete using an oxygen free, purgeable dry hop apparatus, we carbonate in the tank, we closed pressure transfer to kegs that have been 100% purged of oxygen by pushing full volume of sanitizer out using CO2. The kegs themselves last for months and no oxidation issues. Once we put the last one in howlers, it was a matter of 2-3 days and it was turning that brown/purple.

 

[McMullan]

That goes a long way explaining why it was never done before. It’s just a hunch.

 

[marc1]

Any way to set up a counterpressure filler for them with built in CO2 purging? I know they make them for bottles because I used one years ago at a self brew on premise place.

Other than that, make a batch and test out a bunch of methods.

Do an n of 3 or so of each condition to see how it goes, then when you find something promising, up the number to 10 or 20 to confirm that it works consistently.

You could try dosing citric acid and/or metabisulfite, leaving less headspace but still some, fill while flushing with CO2 and then foaming with the CO2 and capping on foam, or some combination of these.

 

[Rob2010SS]

That goes a long way explaining why it was never done before. It’s just a hunch.

Yeah, I'm not an idiot, I get it. However, I'm asking if there's anything that can be done for it in the case of howlers/growlers? Na-Meta seems to help a little according to Brulosophy but I know how it is when you mention that site around here. So was curious on others' thoughts.

 

[Rob2010SS]

Any way to set up a counterpressure filler for them with built in CO2 purging? I know they make them for bottles because I used one years ago at a self brew on premise place.

Other than that, make a batch and test out a bunch of methods.

Do an n of 3 or so of each condition to see how it goes, then when you find something promising, up the number to 10 or 20 to confirm that it works consistently.

You could try dosing citric acid and/or metabisulfite, leaving less headspace but still some, fill while flushing with CO2 and then foaming with the CO2 and capping on foam, or some combination of these.

Thank you for putting some thought into your response, I appreciate it.

I'll have to see about the counterpressure filler for them. Never looked for one but I like that idea, if it exists...

 

[McMullan]

According to Brulosophy! I lost it there.

 

[Rob2010SS]

According to Brulosophy! I lost it there.

Since you clearly don't have anything to add, feel free to see yourself out.

 

[tracer bullet]

Haven't tried it, but I've read here that folks intentionally allow some foam to develop, and let that foam (on the belief it's bubbles of CO2) fill up that last inch or whatever of headspace and push out the "air" that would otherwise be there.

Maybe also consider, post filling to the top via the normal method and waiting and a day or so later, cracking the caps open just a second to let a little CO2 escape? Might get the pressure down to more reasonable or "normal" levels.

There are also of course the mini kegs. Something like this. It's what I use when I have a little extra beer that would otherwise overflow a 5 gallon keg.

https://www.williamsbrewing.com/Gif...eer-Gifts-Under-4000/2-Liter-KegLand-Mini-Keg

 

[Golddiggie]

I would get a counterpressure filler that has a stopper that will work with those growlers. I'd also look to get a ones made by someplace better that could handle the pressures of beer when the thing is filled. I've always filled up, with the tube all the way in (fill from the bottom) and only left the gap from the tube. Zero issues with any bottle breaking.

Are you filling these on demand, as in the ones people bring in, or are you doing swaps of empty growlers for already filled ones? I'd go with the second option if at all possible. That way you can be sure they are cleaned correctly, as well as sanitized, before they get filled.

Something else, the screw tops could be a source of oxidization. IME/IMO, swing top type growlers would have a more positive seal on them. Screw caps have gaps to make them work (between the cap and the glass). where swing tops compress the gasket and create a better seal.

 

[Dgallo]

counter pressure fillers Counter Pressure Filling | The Growler Station | Fresh Craft Beer To Go and Some breweries will wrap electrical tape around their growlers caps to improved the seal.

That said many in my area just invested canners and do 32 oz crowlers because there is so much competition in NEIPA realm that a miss in quality, even due to the customer error (holding on to a growler too long), will cause you to close your doors

 

[Rob2010SS]

Haven't tried it, but I've read here that folks intentionally allow some foam to develop, and let that foam (on the belief it's bubbles of CO2) fill up that last inch or whatever of headspace and push out the "air" that would otherwise be there.

Maybe also consider, post filling to the top via the normal method and waiting and a day or so later, cracking the caps open just a second to let a little CO2 escape? Might get the pressure down to more reasonable or "normal" levels.

There are also of course the mini kegs. Something like this. It's what I use when I have a little extra beer that would otherwise overflow a 5 gallon keg.

https://www.williamsbrewing.com/Gif...eer-Gifts-Under-4000/2-Liter-KegLand-Mini-Keg

I like that mini keg idea!!! Thanks for sharing that!

I've thought about cracking the tops and releasing some of that pressure. However, some of the ones that have blown, literally only took a couple of minutes. We are thinking of going to the standard howler shape where the bottom doesn't have that sharp corner that is susceptible to breaking and we may be able to fill those to the top again, but haven't tested it yet.

Thanks for the ideas!

 

[Rob2010SS]

I would get a counterpressure filler that has a stopper that will work with those growlers. I'd also look to get a ones made by someplace better that could handle the pressures of beer when the thing is filled. I've always filled up, with the tube all the way in (fill from the bottom) and only left the gap from the tube. Zero issues with any bottle breaking.

Are you filling these on demand, as in the ones people bring in, or are you doing swaps of empty growlers for already filled ones? I'd go with the second option if at all possible. That way you can be sure they are cleaned correctly, as well as sanitized, before they get filled.

Something else, the screw tops could be a source of oxidization. IME/IMO, swing top type growlers would have a more positive seal on them. Screw caps have gaps to make them work (between the cap and the glass). where swing tops compress the gasket and create a better seal.

Yeah, I'm for sure going to look into the counter pressure filler idea. I think that might be the best option.

As far as better glass, we're talking about making that move. Surprisingly, finding someone with them in stock has been a challenge. We've tried ordering from 3 different places now and they come back and tell us they don't have them and they have to refund us!

We're filling on demand, but we are doing the swap. They bring in their old one, we have others that have been cleaned and sanitized and fill those and give them back. We run them all through that cycle.

I'll look into the swing top ones as well. Thank you for the input, I appreciate it.

 

[Rob2010SS]

counter pressure fillers Counter Pressure Filling | The Growler Station | Fresh Craft Beer To Go and Some breweries will wrap electrical tape around their growlers caps to improved the seal.

That said many in my area just invested canners and do 32 oz crowlers because there is so much competition in NEIPA realm that a miss in quality, even due to the customer error (holding on to a growler too long), will cause you to close your doors

Yeah we have heat seals that go around the caps and seal them up pretty well. They do have the perforation on one side for easy opening but 99.9% of the edge of the cap is sealed.

We've been to a couple of places local that also do the canners. Had a couple mess those up too!! Ultimately, I'd love to invest in a canner and just can our beers. You're capping on top of the beer in those cans and ultimately, I think that helps preserve it a bit better than growlers.

Thanks.

 

[Golddiggie]

Supply chain BS is hitting everything still. Maybe reach out to the better companies that offer the swing top types. If they don't have any at that time, get put on the list to be contacted as they get some in. Or get some sample units so you can see how things work out and then decide. IME, swing tops seal really well and you can tell visually (easily). I have a couple of growlers here, one from a regional brewery, another off Amazon that are swing top. Hell, you could get some 1L swing top bottles from a supplier to try once you get the counterpressure filler to see how the beer holds up over time. Would be a shorter investment and give you more information sooner.

 

[Silver_Is_Money]

You could simply try adding nothing more than 0.2 grams of pure Ascorbic Acid powder per Liter at bottling. Try it on a small scale. Fill a few Growlers with and a few without (as controls). See if it eliminates the browning caused by oxidation without being a flavor deterrent, and without transitioning into the feared and dreaded Superoxidizer. Compare against the control group at varying time intervals spanning say 4 months.

If you decide to add either Na or K Metabisulfite, and you are selling the beer commercially, be sure to check all requisite laws at all levels, as it may not be legal for commercial use in beer, even if it is legal in wine. And if you sell across State lines....

 

[Knightshade]

That said many in my area just invested canners and do 32 oz crowlers because there is so much competition in NEIPA realm that a miss in quality, even due to the customer error (holding on to a growler too long), will cause you to close your doors

I’ve seen this as well. You can’t find any breweries in my area that even have glass growlers available anymore. Most are more than happy to sell you their branded HydroFlask/Yeti whatever tho.

 

[Knightshade]

and today...I get this email. Extracting foot...from mouth.

 

[sibelman]

As far as better glass, we're talking about making that move. Surprisingly, finding someone with them in stock has been a challenge.

Best of luck, Rob, finding the right (available!) solution.

Not to pile on, but those lovely howlers seem too risky for any carbonated production use, except maybe for in house testing :-l Though for that, maybe a cap with a pressure gauge will provide more nuanced data.

 

[Rob2010SS]

Best of luck, Rob, finding the right (available!) solution.

Not to pile on, but those lovely howlers seem too risky for any carbonated production use, except maybe for in house testing :-l Though for that, maybe a cap with a pressure gauge will provide more nuanced data.

Thanks man, appreciate it.

The funny thing is, is we've been to commercial breweries that use them and we have a couple of them that we purchased (galena brewing, for example). That's why we never predicted we'd have that kind of issue. However, after looking at it from a logical perspective, after we had some explode of course, it makes sense why they're all breaking at the bottom because of that sharp corner.

Next ones we get are going to be the typical howler shape, nothing fancy.

Cheers!

 

[sibelman]

So, two possibilities come to mind: you got a bad batch of glass, or your hazy is/was unusually, er, active. Maybe a good idea to test the second thing even after moving to a new howler/growler product. Cheers!

 

[Rob2010SS]

So, two possibilities come to mind: you got a bad batch of glass, or your hazy is/was unusually, er, active. Maybe a good idea to test the second thing even after moving to a new howler/growler product. Cheers!

By active, you mean still fermenting? No, the exploding glass was happening before the hazy on a different batch. On top of that, we take our time and make sure that the beers are done fermenting. We're not rushing them.

We thought it was a bad batch of glass, so we reached out to the supplier and explained what was happening. We walked through our process of cleaning/sanitizing and what not. He sent us a whole new batch at no charge, marked them to know if they were the new batch when they broke, and sure enough we were having those blow up as well.

On those howlers, the 32oz line is about a 3rd of the way up that angle on the top of the glass. We were filling to the very top which when measured out was 40oz. The investigating we did online seemed to point to the fact that we were overfilling them and CO2 had no where to go, except blow out the bottom.

We did find it weird, because we've taken home plenty of growlers that were filled to the top with no issues. But those howlers were never in that shape, they were always the standard shape. My guess is the "lil genie" shape has an inherent weakness in that spot due to the design, but I could be wrong.

 

[VirginiaHops1]

I can't believe you were blowing out the growlers. Wild

I fill growlers now and then to share and find my hazy beers hold up decently if I purge the crap out of the growler and then cap on foam. Hold up decently is still less than a week. I would not trust any hoppy beer in a growler, especially a hazy one, longer than that

 

[Rob2010SS]

I can't believe you were blowing out the growlers. Wild

I fill growlers now and then to share and find my hazy beers hold up decently if I purge the crap out of the growler and then cap on foam. Hold up decently is still less than a week. I would not trust any hoppy beer in a growler, especially a hazy one, longer than that

Yeah it was not good!

I've tried the purging and it maybe got me an extra day or two out of it. However, even with that, it was only like 3 days before they were pouring a dark brown color.

We are going to go back to the standard shape howler because we feel safer with those. Hopefully they'll hold up better when filled up to the top.

 

[VirginiaHops1]

Yeah it was not good!

I've tried the purging and it maybe got me an extra day or two out of it. However, even with that, it was only like 3 days before they were pouring a dark brown color.

We are going to go back to the standard shape howler because we feel safer with those. Hopefully they'll hold up better when filled up to the top.

Are you making sure to cap on foam too?

 

[Rob2010SS]

Are you making sure to cap on foam too?

When we get the new howlers, in the standard shape, then yes we will go back to capping on foam. However, with these, we can't fill them that high to cap on foam. That'll cause more bombs unfortunately.

 

[VirginiaHops1]

When we get the new howlers, in the standard shape, then yes we will go back to capping on foam. However, with these, we can't fill them that high to cap on foam. That'll cause more bombs unfortunately.

Yeah capping on air in the headspace is very bad. I'd be surprised if a hazy beer even stayed fresh a couple days

 

[Silver_Is_Money]

A number of home brewers who freq this forum have been reporting great success with adding Ascorbic Acid. Not one of them has indicated that it led to the dreaded superoxidizer condition. The key seems to be found within adding an adequate amount.

 

[Rob2010SS]

Yeah capping on air in the headspace is very bad. I'd be surprised if a hazy beer even stayed fresh a couple days

Yeah it was really disheartening. The first hazy we did, we capped on foam and the ones that didn't blow, they kept for a long time. We'd actually fill it so that there was hardly any foam on top and that the liquid was at the top right under the cap. That ended up being 40oz of beer in the howlers that are rated for 32oz.... That's why I want to get back to that and I hope with the standard shape howler, they won't blow like that.

Ultimately, I want us to get a canner. I think that's the best solution personally, but haven't pulled the trigger on a seamer yet.

 

[Rob2010SS]

A number of home brewers who freq this forum have been reporting great success with adding Ascorbic Acid. Not one of them has indicated that it led to the dreaded superoxidizer condition. The key seems to be found within adding an adequate amount.

Yep, you made that comment earlier and I'm going to try it. Hell, if that even gives us an extra 1-2 days, worth it in my opinion.

 

[whattabrau]

We were filling them up to the very top of the glass and capping them. We were practically capping them on liquid.

[...]

Ultimately, after more failures and more breaks, we came to the conclusion that we were overfilling the howlers and the CO2 escaping from the beer was causing them to blow out the bottoms right in that crease in the circled area above.

More likely the culprit was the thermal expansion of the liquid, if you filled cold and let it warm up. The pressure induced by CO2 is self-limiting in the sense that once you reach the equilibrium pressure, the pressure stops rising. Liquids, on the other hand, will increase the pressure [almost] as much as they need to be able to expand. The gas in a container acts as a cushion against the liquid expansion. You can observe thermal expansion by drawing a line on a [long-neck] bottle before moving it in/out of the fridge. It's observable even for the some-degree winter/summer basement temperature swing here.

If you're willing to sacrifice another container, fill it with cold water, cap on liquid, and let it warm up. If it explodes, CO2 wasn't the problem.

tl;dr capping on liquid in an inflexible container is a bad idea regardless of carbonation

(besides cap-on-CO2-foam don't have good suggestions for your actual problem, sorry)

 

[Rob2010SS]

More likely the culprit was the thermal expansion of the liquid, if you filled cold and let it warm up. The pressure induced by CO2 is self-limiting in the sense that once you reach the equilibrium pressure, the pressure stops rising. Liquids, on the other hand, will increase the pressure [almost] as much as they need to be able to expand. The gas in a container acts as a cushion against the liquid expansion. You can observe thermal expansion by drawing a line on a [long-neck] bottle before moving it in/out of the fridge. It's observable even for the some-degree winter/summer basement temperature swing here.

If you're willing to sacrifice another container, fill it with cold water, cap on liquid, and let it warm up. If it explodes, CO2 wasn't the problem.

tl;dr capping on liquid in an inflexible container is a bad idea regardless of carbonation

(besides cap-on-CO2-foam don't have good suggestions for your actual problem, sorry)

Good info! I don't think that was the issue though. Because once filled, they were kept in a fridge, never allowed to get warm, and they were exploding in the fridge (what a mess!).

I talked to the wife about a can seamer. I think that's the best way to solve the issue. Instead of filling 32oz glass howlers, everyone gets (2) 16oz cans! She was not against it!!! LOL.

 

[Golddiggie]

I talked to the wife about a can seamer. I think that's the best way to solve the issue. Instead of filling 32oz glass howlers, everyone gets (2) 16oz cans! She was not against it!!! LOL.

IMO/IME, canning is going to be the better option. Especially with opting for the 16oz can for a standard fill. Instead of trying for the crowler size (32oz can). Lower cost to package means the customers will spend less without having to purchase an empty growler earlier (and do the swap). Add to that lower operational costs for you in that you won't need to clean/sanitize turned in growlers moving forward.

Maybe offer people that bring in the old issue growlers an extra can (or two) for the exchange (whatever equates the $$ they spent on them).

Depending on your batch sizes, you might want to look into one of the setups that fills cans, then seals them without you needing to perform all of the tasks. From my earlier research, there are some choices that are pretty reasonable in price. Especially for the features. It would shorten the time it takes to package the batch as well. Less time you need to spend doing that is more time you can spend on other things (or having a pint ).

I'm waiting for the LHBS I shop at to get the KegLand label applying machine in (ordered last week). Lower cost (to me) than from MoreBeer (who wanted $200 for 'freight shipping' BS).

 

[Rob2010SS]

IMO/IME, canning is going to be the better option. Especially with opting for the 16oz can for a standard fill. Instead of trying for the crowler size (32oz can). Lower cost to package means the customers will spend less without having to purchase an empty growler earlier (and do the swap). Add to that lower operational costs for you in that you won't need to clean/sanitize turned in growlers moving forward.

Maybe offer people that bring in the old issue growlers an extra can (or two) for the exchange (whatever equates the $$ they spent on them).

Depending on your batch sizes, you might want to look into one of the setups that fills cans, then seals them without you needing to perform all of the tasks. From my earlier research, there are some choices that are pretty reasonable in price. Especially for the features. It would shorten the time it takes to package the batch as well. Less time you need to spend doing that is more time you can spend on other things (or having a pint ).

I'm waiting for the LHBS I shop at to get the KegLand label applying machine in (ordered last week). Lower cost (to me) than from MoreBeer (who wanted $200 for 'freight shipping' BS).

I don't think I've seen one of those setups that fills and seals. I've only seen the seamers that do just that - seal the can. I'll have to search for it. Our typical batch size is 1/2 bbl. But on occasion, we'll do a smaller batch in our 7 gal uni.

 

[Golddiggie]

Might not be worth it for 1/2bbl and smaller batch sizes. IIRC, the setups range in the $20-30k range (to start). With those filling four cans at a shot, then sending them to the seamer section. Some also apply shrink wrap labels to the cans before filling them. LOTS of options out there to pick from. I'll be looking to get something when I hit the 1bbl batch size (and above). Since it will seriously shorten the time it takes to package a batch.

One from these guys might do the trick for you:
https://www.sskeg.com/can-filling-machine

 

[jwhazel]

Not an answer to "something that can be added to a keg" but rather for "something added to the growler" - argon gas. It displaces oxygen rather than just mixing with it like co2. I've had success bottling with just a few quick squirts in the headspace, no oxidation for months.

 

[Rob2010SS]

Not an answer to "something that can be added to a keg" but rather for "something added to the growler" - argon gas. It displaces oxygen rather than just mixing with it like co2. I've had success bottling with just a few quick squirts in the headspace, no oxidation for months.

Where the hell do you even get that at?? LOL.

We took, what I believe to be, the best step in preventing/slowing/eliminating oxidation - we bought the Cannular Pro Seamer. It'll be here Friday. We're going to move away from the howlers all together. We'll fill 1 keg for us to have on tap and can everything else. We'll see how that goes.

 

[jwhazel]

Where the hell do you even get that at?? LOL.

At the homebrew level: Amazon.com: ArT Wine Preserver | Premium Wine Preservation | Argon Gas | Wine Saver Spray | Eliminate Oxidation: Home & Kitchen
Larger scale/commercial level: pretty much any airgas or welding supply shop. Just like buying a co2 tank.

 

[wepeeler]

I know this has probably been discussed/answered in other threads somewhere. However, my google-ability is not very good and I never know the right words to search for to find what I'm looking for, LOL.

Here's the question I'm trying to answer: Is there something that can be added to a keg that can prevent, or help reduce, oxidation in hazy IPAs when filling howlers/growlers?

Here's the backstory....
We have a group of people that we fill howlers and growlers for whenever we put something new on tap. We bought a bunch of these howlers with our logo on them...

View attachment 758209

In 2020, we brewed a hazy that we shared with the group. At that point, these howlers were fairly new and we didn't have a lot of experience with them. We were filling them up to the very top of the glass and capping them. We were practically capping them on liquid. The thought process was that if we fill them that full, there's no room for air or oxygen, and if we don't have any oxygen in the howler, the beer should be well protected.

We started having a few of these explode. They would all break here in the circled area below...

View attachment 758210

Ultimately, after more failures and more breaks, we came to the conclusion that we were overfilling the howlers and the CO2 escaping from the beer was causing them to blow out the bottoms right in that crease in the circled area above. Since we have stopped filling to the top of the glass and only filling to the 1L / 32oz mark on the glass, we have had no blow outs.

Fast forward to 2021, we brewed another hazy and shared with the group. We now filled the howlers to the 1L / 32 oz line and people were drinking them fast enough that the flavor wasn't affected too much, but when we got a couple of pictures of the beer, it was clearly oxidized. It went from bright yellow to that well known dark brown, almost purple, oxidized look. We started sticking a CO2 tube in the neck of the howler when filling to try and flush it out and it helped some of them but not all of them.

We're going to be brewing another hazy here in a couple of months. We want to be able to have people enjoy this the way it was meant to - bright and fresh! I know howlers and bottles are not ideal for hazies, and that's why a lot of people just don't bottle them. I've also seen talk of adding different ingredients at time of kegging to help prevent oxidation and improve shelf stability.

What are my options here as far as additions that can be added to the keg to possibly help reduce this - if there are any options at that?
- I know those K-Meta and Na-Meta ingredients are antioxidants but not sure if those can be added to fermented, carbonated beer without affecting flavor.
- Can they just be added to the howler or do you add them to the keg?

As far as how we brew these, we're not doing LODO by any means, but once the beer is in the fermenter, it doesn't see oxygen again. We ferment in a unitank, we're dry hopping after fermentation is complete using an oxygen free, purgeable dry hop apparatus, we carbonate in the tank, we closed pressure transfer to kegs that have been 100% purged of oxygen by pushing full volume of sanitizer out using CO2. The kegs themselves last for months and no oxidation issues. Once we put the last one in howlers, it was a matter of 2-3 days and it was turning that brown/purple.

I'm banking on faulty growlers. I've never had a bottle/growler crack from filling to the tippity top from a picnic tap in over 5 years. I'd say I fill them weekly to share.

Could there be some sort of secondary fermentation happening? Infection?

Just saw that you bought a canner. Best of luck with that!

 

[Rob2010SS]

I'm banking on faulty growlers. I've never had a bottle/growler crack from filling to the tippity top from a picnic tap in over 5 years. I'd say I fill them weekly to share.

Could there be some sort of secondary fermentation happening? Infection?

Just saw that you bought a canner. Best of luck with that!

I'm with you on the faulty growlers. We've taken growlers home from breweries and they fill them up to the brim and cap them, and no issues. However, we've never had one of the lil' genies from a brewery. It was always the standard shape howler.

I'm still a firm believer that something with the design of this particular shape makes it susceptible to breaking there.

I don't believe there's a secondary fermentation or infection happening. Reason being is that we had some explode as fast as 5-10 min after filling. They didn't even make it off of my kitchen counter before exploding. That's too fast for that to be the cause.

Yep, I think the canner will be a great addition! Thanks for the input.

 

[rizziot]

I've have this issue when I brew Hazy IPA's and want to take it places . I was looking at pressurized growlers, but when getting a hazy from a brewery there would still be 'some' oxidation when the fill it right? Would just having a pressurized growler be enough (via purging after fill) to keep it fresh? I've been trying to figure this out for a bit and found this cap at craft master growlers. It 'looks' like it would let you do a oxygen free transfer from keg to growler, Yes / No? Keg Cap | Ball Lock Draft Adapter For Pressurized Growlers .

I've also read that Ascorbic Acid at packaging works pretty well too, just haven't tried it personally.