Filling Growlers

[milo_leon]

Hello all!

My friend and I have a small growler club going on (we all basically chip in for buying grain/hops/yeast/etc and we brew then split the batch).

We keg and fill growlers for "distribution" to our friends. We are struggling with foaming while filling our growlers, as we feel that we are losing a lot of beer to foaming.

I've calculated that a 5gal keg holds about 18900 mL of beer. We use 750mL swingtop growlers, so we should be able to fill about 25 growlers assuming no losses.

We are able to fill consistently about 13-15 750mL growlers. We also do serve maybe ~3 growlers worth in pint glasses before the keg kicks. My math is telling me we should have about 5-7 fills left? Am I really losing that much to foam?

Our process is we drop the psi to 1, vent excess pressure, then start the flow. I will open and close the shutoff valve occasionally to regulate the fill rate, and despite the low PSI we always end up with a lot of foam coming out of the growler before we see beer.

My fill tube is about 1 foot flexible tubing with another 1 foot of rigid plastic that goes inside the growler - should I get a longer tubing as I read that will increase the backpressure and reduce foaming?

Any tips or ideas how we can reduce our losses? Since we brew at a small scale with 5 gal batches, we want to maximize how much beer we can get out of the keg.

 

[mongoose33]

Are your growlers cold when you fill them? When cold beer warms, the CO2 comes out of solution, i.e., as foam. If you're filling warm growlers, you're contributing to foam.

Also, are you filling the growlers from the bottom? The fill tube should be at the bottom of the growler, so that as beer enters it's not exposed to anything other than more beer. I sanitize mine in Star San before using it, and it goes right to the bottom of the growler.

i use a growler filler that plugs into the faucet (it's a Perlick faucet) and the filler tube is about...12 inches long or so. Just long enough to reach to the bottom of a growler. I also occasionally fill bottles this way, so either you're too carbonated coming out of the faucet, the growler is too warm, or you do not have enough back pressure--though if that were truly a problem, you'd see it when you fill pints. Do you?

 

[beernutz]

13 to 15 growler fills plus 3 growler fills in pint glasses is 16 to 18 total equivalent growlers filled per 5 gallons. Since 5 gallons should provide 25 fills of 750 mL bottles it looks like you're losing between 7 and 9 growler fills, not 5 to 7.

Are you sure your growlers aren't 1 liter? That would explain the anomaly.

 

[milo_leon]

Are your growlers cold when you fill them? When cold beer warms, the CO2 comes out of solution, i.e., as foam. If you're filling warm growlers, you're contributing to foam.

Also, are you filling the growlers from the bottom? The fill tube should be at the bottom of the growler, so that as beer enters it's not exposed to anything other than more beer. I sanitize mine in Star San before using it, and it goes right to the bottom of the growler.

i use a growler filler that plugs into the faucet (it's a Perlick faucet) and the filler tube is about...12 inches long or so. Just long enough to reach to the bottom of a growler. I also occasionally fill bottles this way, so either you're too carbonated coming out of the faucet, the growler is too warm, or you do not have enough back pressure--though if that were truly a problem, you'd see it when you fill pints. Do you?

Yes, we chill our growlers prior to fill and fill from the bottom. I also move the tube up so I can fill up close to the brim.

I also tend to pour a small glass of beer prior to filling so the tube is cold/primed as well. How do I gauge if there is enough backpressure as I do see some beer "floating" back to the keg when I turf off the fill?

 

[TheMadKing]

make sure your beer and growlers are cold (but not frosty, If they are frosty they will foam more), reduce your pressure even more, make sure you aren't sucking air into your tubing at the connections, make sure your outlet is submerged in beer but not pressed against the bottom of the growler, and keep the faucet/tap wide open the whole time. That last point seems counter-intuitive but the smoother the flow, the less CO2 is released from solution, so don't try to regulate the flow with anything but pressure.

 

[Terek]

i fill growlers all the time. i see the most foam when i am trying to "regulate" the speed of the fill, by shutting off, and on the valve. do not do this, once beer starts to flow, it will foam less. Also, i would not lower the psi of the co2 while filling. It needs a good flow to keep the foam down. I also notice that as the keg gets closer to empty, i get more foam. I have now started to keep my kegs at 8 psi, instead of 10-12 psi. this has also helped a lot. It seems that 10-12 is too much over 4-5 weeks time. It just gets too carbed up after a while, thus foams more.

 

[ncsuwerewolf]

I pour mine straight from the faucet into room temp growlers with no issues thoI am dropping the pressure to about 3 psi vs the 11 i normally pour at.

 

[TheMadKing]

i fill growlers all the time. i see the most foam when i am trying to "regulate" the speed of the fill, by shutting off, and on the valve. do not do this, once beer starts to flow, it will foam less. Also, i would not lower the psi of the co2 while filling. It needs a good flow to keep the foam down. I also notice that as the keg gets closer to empty, i get more foam. I have now started to keep my kegs at 8 psi, instead of 10-12 psi. this has also helped a lot. It seems that 10-12 is too much over 4-5 weeks time. It just gets too carbed up after a while, thus foams more.

Few issues:

Lower pressure/flow reduces foam due to the reduced friction with the tubing walls. Higher pressure/flow = more foam. No getting around the physics of it.

There should be no change in carbonation levels with less beer in the keg at all if the head pressure is constant

You can check exactly how much carbonation is in your beer for a given pressure at a given temperature.


Time and volume have nothing to do with it at all. Once your beer is carbonated, that carbonation level will not change unless the temperature or the pressure change.

I agree with the "don't try to regulate flow" advice though.

 

[pvpeacock]

I had the same problem until I bought this: http://brulosophy.com/2016/07/14/the-bru-bottler-update-how-to-build-your-own/

You can build your own and it works like a charm. The ability to hold the pressure in the growler with the stopper and then slowly bleed it out while it fills prevents foaming. Yes, some foam/beer spills out when you stop the flow and remove the wand, but that is minimal compared to using a wand or hose without the stopper.

 

[milo_leon]

13 to 15 growler fills plus 3 growler fills in pint glasses is 16 to 18 total equivalent growlers filled per 5 gallons. Since 5 gallons should provide 25 fills of 750 mL bottles it looks like you're losing between 7 and 9 growler fills, not 5 to 7.

Are you sure your growlers aren't 1 liter? That would explain the anomaly.

Yes, I am using 750mL growlers swingtop from HF/Treehouse/Tired Hands. I am filling to the very brim so that should be giving me 750mL?

 

[milo_leon]

make sure your beer and growlers are cold (but not frosty, If they are frosty they will foam more), reduce your pressure even more, make sure you aren't sucking air into your tubing at the connections, make sure your outlet is submerged in beer but not pressed against the bottom of the growler, and keep the faucet/tap wide open the whole time. That last point seems counter-intuitive but the smoother the flow, the less CO2 is released from solution, so don't try to regulate the flow with anything but pressure.

My PSI is at 1, how do I reduce this even further

The last time we did fills, I left faucet wide-open and used the shutoff valve at regulator to cut off pressure if I needed to slow down the fill. Process was much smoother that time, but still lost some to foaming. Will double-check the connections to make sure no air is getting in.

 

[milo_leon]

I had the same problem until I bought this: http://brulosophy.com/2016/07/14/the-bru-bottler-update-how-to-build-your-own/

You can build your own and it works like a charm. The ability to hold the pressure in the growler with the stopper and then slowly bleed it out while it fills prevents foaming. Yes, some foam/beer spills out when you stop the flow and remove the wand, but that is minimal compared to using a wand or hose without the stopper.

I have the very same thing but I don't have the stopper. Does the stopper really help with foaming?

 

[pvpeacock]

Yes, the stopper is the key to preventing/minimizing foaming.

 

[TheMadKing]

My PSI is at 1, how do I reduce this even further

The last time we did fills, I left faucet wide-open and used the shutoff valve at regulator to cut off pressure if I needed to slow down the fill. Process was much smoother that time, but still lost some to foaming. Will double-check the connections to make sure no air is getting in.

Disconnect the gas from the keg while filling, and just give it a burst of CO2 when flow gets too slow.

There should be no reason to slow down a fill. Your growler is either empty or full. If it's not full, just keep filling it at the same speed until it is.

If it's filling so fast that you don't have time to react, then something is wrong with your regulator. 1 PSI should take about 30 seconds to a minute to fill a growler. It should be slow and smooth.

Your process should be:

Charge keg to 1-2 PSI and disconnect gas
Insert tube into a cool/sanitized growler about 1cm from the bottom
Open the tap to full open
Wait for the growler to fill to the top
close the tap
remove the tube
cap it

If flow stops during the fill, just give your keg a quick burst of CO2 at 1PSI

This is what I do, and I fill growlers and bottles with a party tap and lose maybe a tablespoon of beer per fill and have no issues with flat beer or anything.

One other question, are you trying to fill your growlers until there is liquid at the very very top of the bottle? or are leaving headspace/foam in the neck?

 

[pvpeacock]

If you use a stopper, you do not need to reduce the psi in the keg because the pressure will equalize between the keg and the growler. Once equal, the beer will stop flowing to the growler. You then release a little pressure at a time by letting the stopper push slightly out of the growler or squeezing it a little to release the pressure and beer flow continues until the pressure equalizes again.

 

[Yesfan]

If you use a stopper, you do not need to reduce the psi in the keg because the pressure will equalize between the keg and the growler. Once equal, the beer will stop flowing to the growler. You then release a little pressure at a time by letting the stopper push slightly out of the growler or squeezing it a little to release the pressure and beer flow continues until the pressure equalizes again.

This is what I do. I bottle at full pressure with no issues this way.

 

[mongoose33]

I have the very same thing but I don't have the stopper. Does the stopper really help with foaming?

It's hugely helpful. It works just as described above. I hadn't thought about connecting that to my growler filler, but I'm sure going to try it.

Here's what my bottling wand looks like; the vinyl tubing at the top fits over a picnic tap snugly. The plastic tube is from a bottle filler, just cut off the tip and angled the part that goes into the bottle so it can ground and then fill.

I actually have a "last straw" bottle filler from NB, but this approach is just about as slick.

 

[TheMadKing]

It's hugely helpful. It works just as described above. I hadn't thought about connecting that to my growler filler, but I'm sure going to try it.

Here's what my bottling wand looks like; the vinyl tubing at the top fits over a picnic tap snugly. The plastic tube is from a bottle filler, just cut off the tip and angled the part that goes into the bottle so it can ground and then fill.

I actually have a "last straw" bottle filler from NB, but this approach is just about as slick.

View attachment 377983

Agreed that this is a good system, and superior to adjusting pressure in most cases, but I have growlers with 5 different mouth sizes, so on my system, it's easier just to disconnect the gas and fill with a bottling wand from a party tap... Different strokes as they say

In the end you'll probably have to experiment and figure out what works on your system.

 

[beernutz]

Yes, I am using 750mL growlers swingtop from HF/Treehouse/Tired Hands. I am filling to the very brim so that should be giving me 750mL?

That just seems like too big of a difference between the theoretical amount of growlers you can fill compared to the actual to be accounted for by foam.

Good luck.

 

[Terek]

Few issues:

Lower pressure/flow reduces foam due to the reduced friction with the tubing walls. Higher pressure/flow = more foam. No getting around the physics of it.

There should be no change in carbonation levels with less beer in the keg at all if the head pressure is constant

You can check exactly how much carbonation is in your beer for a given pressure at a given temperature.


Time and volume have nothing to do with it at all. Once your beer is carbonated, that carbonation level will not change unless the temperature or the pressure change.

I agree with the "don't try to regulate flow" advice though.

you can "science it up" all you want, but when I watch it happen in front of me, its hard to deny. You can brush off my methods if ya want. Ill just be over here filling my growlers with very little foam.

 

[TheMadKing]

you can "science it up" all you want, but when I watch it happen in front of me, its hard to deny. You can brush off my methods if ya want. Ill just be over here filling my growlers with very little foam.

.."science it up?"

Good lord, and here I thought we lived in 2016 not 1145.

The nice thing about science is that it's true whether you want it to be or not.

I never once claimed that you were lying, or that your method did not work for you. In 90% of cases however, your advice was wrong.

If you are filling at full pressure with no foam there is something else going on that explains it. You may have very long 3/16" ID lines that provide enough back pressure to prevent foaming, your regulator may be off, your beer may be undercarbonated, you might have a leak in your kegs... There's any number of things that could explain how foam can be reduced at serving pressure. Just please don't claim that physics doesn't apply to you, that's asinine.