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First foray into kegging

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gryphonkd

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I know this topic has probably been done to death, but there are a few things still not clear to me.

Question 1 - Keg Shelf-life

I am reading several articles that kegs must be kept refrigerated at all times or they will sour/spoil/infect etc..
I'm thinking about a beer fridge to store kegs in, which would be nice... can force carb more easily etc... but i'll never serve it out of the fridge when i take kegs to parties etc.

...But must I keep them refrigerated? That doesn't make sense to me at all.
I often rack my brews to secondary for 2 weeks, then to keg - sometimes directly to keg -- and then prime for secondary, allowing them to pressurise in the keg.
If also give them a blast of C02 and blowoff the top layer of air so C02 is sitting on it.
(Although...now that i've just typed that.. does that leave them enough Oxygen for secondary stage?)

In any case, assuming they ferment out the priming sugar and pressurize properly; If my keg is sanitised and the beer is under C02, how is that any different to a bottle?
I store beer in bottles at room temp (20deg) for months, and they dont spoil; so why should a keg?
Even if i dispense over several weeks, the beer is always under C02, so where is the problem?

Question 2 - Keg dispensing pressure / line balancing.

I think i understand the principles here, but still having difficulty.
Firstly an ideal volume of C02 is dissolved to the beer. Lets just say that volume equates to 16psi at room temp. (don't want to get into the table of C02 volumes; pressures, temps etc. that's not the point)

When dispensing, if i drive the keg with anything less that 16psi (or whatever is required to match the primed keg pressure) then pressure will leak back through the bleed valve on the regulator.
Yes I know i can fit a one-way valve; but all that does is ensure that I must be putting enough out of the regulator to overcome the keg pressure; which is going to be about 16psi.
So I don't see how anyone can drive a keg with low pressures, without first bleeding pressure off the beer, which will flatten it, will it not?

If we accept the higher regulator pressure as a requirement; then you need to balance the output of the keg, so that the pressure is dropped over the resistance of the line, leaving you with a useable pressure at the tap, say 2psi.
I know there are a number of factors one can change to achieve this: line material, inner diameter of line, lengthen line, elevate line etc.

My problem is, looking at many guides eg.
http://www.kegking.com.au/balancing%20your%20keg%20system.html

I'm finding that I need a MUCH longer line than suggested to slow the flow rate to acceptable and stop beer foaming.

Scenario1. I have a 9L keg refrigerated to 4deg and saturated at about 15psi. Consequently setting the reg to 15psi, and then running a 3-4m beer line with ID of 4mm - the beer still comes out far too quick and foamy. This of course knocks about half or more of the C02 out by the time it settles in the glass.

I can't lower the pressure on the reg, or the beer will bleed C02 - so, my solution can only be to run more line?

Scenario2. I have a 19L keg at room temp saturated at about 10psi (only forced carbed for 1 day) - Consequently setting the reg to 10psi, i run it out of the keg into 10m of copper coil in an ice-chest ( running though 5m of 3/8 then 5m of 1/4 copper (not by choice, making do with odds and ends))
then out another 2 or so metres of 4mm beer line.
Beer arrives in the glass at about 5deg (nice) and not too fast that it foams.
So a hugely long line has balanced me out.

Is this a good way to do it? Am I missing some key concepts in all of this?
When i have to drive this system harder - which i will with higher volume C02 beers -- i am thinking about an inline flow valve to restrict flow.
Are flow impedances a really bad thing? - they must create turbulance in the liquid - does that create foam?

I trust many of you experienced keggers understand and have overcome these issues one way or another.

Many Thanks.
 

gryphonkd

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Just a further thought... will a reverse flow valve on the gas line actually sort me out here?
i.e. if its just a one way flow valve... then it will only start to push C02 past the valve into the keg when I wind up the regulator to just above the keg back pressure.
Perhaps this way I can wind it up slowly with the beer tap open, until I get an acceptable flow rate out?
 

Amber Fluid

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gryphonkd said:
I know this topic has probably been done to death, but there are a few things still not clear to me.

Question 1 - Keg Shelf-life

I am reading several articles that kegs must be kept refrigerated at all times or they will sour/spoil/infect etc.. Can keep kegs unrefrigerated, no problems. Just keep them in a cool place and they're fine for quite sometime.
I'm thinking about a beer fridge to store kegs in, which would be nice... can force carb more easily etc... but i'll never serve it out of the fridge when i take kegs to parties etc.

...But must I keep them refrigerated? No That doesn't make sense to me at all.
I often rack my brews to secondary for 2 weeks, then to keg - sometimes directly to keg -- and then prime for secondary, allowing them to pressurise in the keg.
If also give them a blast of C02 and blowoff the top layer of air so C02 is sitting on it.
(Although...now that i've just typed that.. does that leave them enough Oxygen for secondary stage?) if you are gassing kegs with the Co2 then no oxygen is needed. If you are bulk priming into the keg then no need to blow of the O2. As you said, the yeast will consume this which in turn helps them to carbonate your keg. If I prime in the keg with sugar then I'll usually just throw the sugar syrup into the keg and rack the beer on top and no need to purge.

In any case, assuming they ferment out the priming sugar and pressurize properly; If my keg is sanitised and the beer is under C02, how is that any different to a bottle? bottles are smaller and you will have troubles connecting a tap them. Kegging is convenient.
I store beer in bottles at room temp (20deg) for months, and they dont spoil; so why should a keg? 1 keg = about 27-30 bottles i.e. far less work and as mentioned above, convenient. Your keg shouldn't spoil either so why should you bottle?
Even if i dispense over several weeks, the beer is always under C02, so where is the problem?Who said there is a problem?... I have had 1 particular keg on tap now for 13 months now and there is no problem.

Question 2 - Keg dispensing pressure / line balancing.

I think i understand the principles here, but still having difficulty.
Firstly an ideal volume of C02 is dissolved to the beer. Lets just say that volume equates to 16psi at room temp. (don't want to get into the table of C02 volumes; pressures, temps etc. that's not the point)

When dispensing, if i drive the keg with anything less that 16psi (or whatever is required to match the primed keg pressure) then pressure will leak back through the bleed valve on the regulator. Use a one way valve (NRV) but Co2 should not bleed back through your regulator anyway. If the C02 has nowhere to go then it will be absorbed into solution until the headspace of the keg is the same pressure as the volume of C02 in solution.
Yes I know i can fit a one-way valve; but all that does is ensure that I must be putting enough out of the regulator to overcome the keg pressure; which is going to be about 16psi.No, a NRV will stop C02 being returned up the lines. Their purpose does not ensure that you must put enough out of the reg to overcome keg pressure.
So I don't see how anyone can drive a keg with low pressures, without first bleeding pressure off the beer, which will flatten it, will it not?You can drive a keg at low pressures without having to bleed pressure off the beer. Just carbonate the beer to your desired volume whether that is high or low makes no difference.

If we accept the higher regulator pressure as a requirement; then you need to balance the output of the keg, so that the pressure is dropped over the resistance of the line, leaving you with a useable pressure at the tap, say 2psi.
I know there are a number of factors one can change to achieve this: line material, inner diameter of line, lengthen line, elevate line etc.

My problem is, looking at many guides eg.
http://www.kegking.com.au/balancing%20your%20keg%20system.html

I'm finding that I need a MUCH longer line than suggested to slow the flow rate to acceptable and stop beer foaming. Generally most people can get away with starting at about 3m and cutting back to find your suitable length. If your kegs are positioned a long way away then start with more line.

Scenario1. I have a 9L keg refrigerated to 4deg and saturated at about 15psi. Consequently setting the reg to 15psi, and then running a 3-4m beer line with ID of 4mm - the beer still comes out far too quick and foamy. This of course knocks about half or more of the C02 out by the time it settles in the glass.

I can't lower the pressure on the reg, or the beer will bleed C02 - so, my solution can only be to run more line? Lower the pressure. You seem to be worried about things not worth the worry. If you can't pour at 15PSI, in this scenario, then don't. Just back it off to a pressure you want to pour at.

Scenario2. I have a 19L keg at room temp saturated at about 10psi (only forced carbed for 1 day) - Consequently setting the reg to 10psi, i run it out of the keg into 10m of copper coil in an ice-chest ( running though 5m of 3/8 then 5m of 1/4 copper (not by choice, making do with odds and ends))
then out another 2 or so metres of 4mm beer line.
Beer arrives in the glass at about 5deg (nice) and not too fast that it foams.
So a hugely long line has balanced me out.

Is this a good way to do it? Am I missing some key concepts in all of this? If you want less line then use a tap with a flow restrictor.
When i have to drive this system harder - which i will with higher volume C02 beers -- i am thinking about an inline flow valve to restrict flow.
Are flow impedances a really bad thing? - they must create turbulance in the liquid - does that create foam? Well, yeah... turbulence will create foam. However, flow restrictors are made for that purpose so why do you think you will have a problem if using one. If it doesn't do what it is intended then send it back and get one that does.

I trust many of you experienced keggers understand and have overcome these issues one way or another.

Many Thanks.
To top it off, I reckon you are worrying more than you have to....

1/ NRV's are cheap considering the possible outcome if not using one; they are a must imo. If you don't have one then you should get at least one.
2/ if you don't like having the length of line then use a restrictor of some sort. I'd recommend a tap with a flow restrictor on it and you can get them cheap these days.
 

gryphonkd

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Continuing the kegging experiment.

I don't have a keg fridge; not for storing kegs, or dispensing them, and i'm not likely to get one. Lack of space and permission!
What I have is a shower in the guest ensuite in the middle of the house; so very stable temperature of around 18deg -- but up to 25 after a string of HOT days.
This is where my kegs are stored.

Now comes the issue of how to dispense.
I have to cool on delivery; so to achieve as this, I run each beer line through cooling coils (about 10m of thin 1/4" copper tubing) immersed in ice in an insulated esky, before delivery to the tap.
This has proven to drop the temperature nicely by as much as 20degrees (25 -> 5) as it is pulled through.

I would reckon this would be a reasonably common scenario for many enthusiast brewers that dont have keg fridges and wish to dispense kegs in a portable manner.

Now i'll bring the topic back to force/artificial carbonation; according to charts, if I want to impart approx 2.5 CO2 vols, in a 25deg environment, I need 33psi (230kpa) to sufficiently carbonate.
Ignoring the rapid absorption method, and sticking with the idea of just setting it to the pressure required to reach the desired volumes over time.
As a side note; even if I was naturally carbing to 2.5 vols - at this temperature of 25, the pressure in the keg must also equal 33psi.


The downside of carbing without a fridge, is of course dealing with these higher pressures when dispensing.
In order to serve these kegs, theory would say that I need to serve at 33psi to ensure the beer in keg doesnt flatten in any way during the session.
Of course balancing 33psi; by way of line resistance to take 30+psi out before the tap means some seriously long and small lines.

As I mentioned, I already have long lines, necessistated by the use of the cooling coil length; which is great - and from a flowrate perspective, everything is working really nicely anywhere between 15-20psi (haven't pushed it higher yet; as my current dispensing reg only goes up to 20)
In theory though; if I try to dispense at anything less than the starting pressure on the keg; the beer will run without the regulator until the keg pressure drops to below what is dialled on the reg (NRV fitted), at which point the reg will start to drive.

Either that, or I suppose you just 'bleed' the keg off a bit down to a pressure the dispensing setup can handle (eg 15 psi) and go from there.
I imagine by the end of the session though, the keg would need to sit back on 33psi for a few days to get it ready for the next session.

So far I havnt had a problem as I don't think i've actually had much more than 1.5vols in keg (for reasons that I am now addressing) So 15psi has worked fine, and the beer doesn't flatten any further.

So this post is really about potential problems and solutions with 'room temperature' kegs, carbonated to 2.5vols, then being served at room temperature and cooled on delivery.
I am expecting I will have to 'bleed' pressure off before serving, and then pump them back up after a session.

I suppose like a bottle of coke - once you take the lid off - i.e. zero pressure, the carbonation stays dissovled in solution for an hour or so.
So i'm guessing if i'm halving the pressure on the keg before serving, i'll get away with several hours -- but will have to recarb before the next session.
 

GalBrew

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The lower the temp of your finished beer the longer it will last (or the slower it will degrade). Chemical reactions (spoiling) are slowed down by lower temperatures, that is why the fridge and freezer exist. What is Charlie Bamforth's formula anyone? Something like for every 10deg drop in beer temp the rate of decay halves??
 

felten

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The rule of thumb is for every 10c increase, the rate of many reactions will double. But again it's only a rule of thumb.
 

gryphonkd

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Am I the only one storing, carbing and serving (with realtimecooling) at room temp? really?
If everyone bottles and stores bottles at room temp for months - why is it so different for kegs?
 

felten

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Because setting up an ice bank every time you want to pull a pint is a massive PITA?
 

GalBrew

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gryphonkd said:
Am I the only one storing, carbing and serving (with realtimecooling) at room temp? really?
If everyone bottles and stores bottles at room temp for months - why is it so different for kegs?
Thanks Felten,

Most people force carb their kegs, so the beer is in a finished state once in the keg. Bottled beer however is bottle conditioned and needs to be at a higher temp to properly carbonate in a reasonable time. The active yeast in a bottle conditioned beer also allows for the consumption of any oxygen in the beer thus preventing oxidation. Up to a certain degree, the beer will improve in the bottle with increasing time (that's why it is called conditioning), you will notice Coopers beers have a best after date rather than a best before for the same reason. When a forced carbed, kegged beer is stored at fridge temps that will put any remaining yeast to sleep (not that they have any sugar to eat) thus removing this layer of protection from kegged beer.

You will also notice in different threads people complaining (rightly so) about bottled beer transported and stored at high temps, which can make it taste like crap (see the Sail and Anchor thread for example) for an array of reasons, try it yourself it does the beer no favours. So really it is ideal to always store beer in a coolroom or fridge to get maximum shelf life. If you ever go to a you brew it style place, put some of the beer in a fridge and some at room temp. The difference will shock you, the cool-stored beer will remain 'drinkable' (I use that term loosely) and the rest will end up tasting full of off flavours and even develop gushers.

You are flying in the face of hundreds of years of traditional cellaring wisdom if you store your beer at room temp if you wish to keep it for more than a couple of months (give or take).
 

Nick JD

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gryphonkd said:
I don't have a keg fridge; not for storing kegs, or dispensing them, and i'm not likely to get one. Lack of space and permission!
Why not just get a carbonator cap or two. Transfer off your warm beer (1.5L) into a couple of 2L PET bottles, put them in the fridge. When they are cold, pop on the carbonator cap and force carbonate them.

If you don't finish the whole bottle, just put some more CO2 in.
 

GalBrew

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gryphonkd said:
I don't have a keg fridge; not for storing kegs, or dispensing them, and i'm not likely to get one. Lack of space and permission!
So why are you kegging?
 

gryphonkd

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I'm trying to keg, with the hope that I can serve with more ease and convenience at BBQs/Parties, than bottles.
I'm expecting/hoping to be able to serve any given keg across a couple of events, maybe over 2-3mnths max.
Plus its pretty damn cool to have a couple of taps running at a BBQ compared to a load of bottles hanging around.

I am not wanting to fly in the face of standard practice for the sake of it.
Just trying to understand the underlying principles and limitations so I can maximse the result.

Setting up an IceBank could be a PITA, but i'll only be using these Kegs for social events, so not a big deal to spend $5 on ice each time.
I drink from bottles for my own purposes at home - don't drink enough to warrant having it on tap.

I will experiment between force carbing (purging the headspace of 'air'). AND sugar priming , leaving 'air' in the headspace and the keg conditioning for a few weeks.
Either way, it should not oxidise, and once carbonated, by either means, should be protected by CO2.

The biggest downside I can seen with roomtemp kegs is the pressures you need to carb at; and deal with when serving.
 

GalBrew

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You should probably stick to keg conditioning then, but the keg needs to be full. To force carb, the beer needs to be chilled as a cooler liquid will be able to hold more CO2 in solution, so that is not going to be an option for you. Just put your dex into the keg, fill as per normal purge the headspace with CO2.

Just plan your keg brews to be ready right when you need tham and don't have them hanging around for extended periods and you should be ok.
 
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If you don't have a fridge to keep your kegs chilled, then force carbonating isn't really an option for you, as GalBrew explained.

Natural carbonation should work perfectly. Add your dextrose and beer to the keg, apply co2 under pressure, (to ensure the keg is sealed) and leave it until you are having a party.

To purge or not is probably debatable, I have purged the air and my kegs still carbonate, however I can see that it might not be necessary or even best practice.

Chill and serve.
 

gryphonkd

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As for whether or not to purge with natural carbing - my understanding of the theory is this:

1 - Naturally carbing the keg; the beer will need oxygen to ferment out the priming sugar.
2 - If carefully xfering the beer to keg - there will be very little oxygen in solution.
3 - if injecting Co2 into keg; even if you dont purge the headspace; it is heavier, and will sink to sit directly onto the beer; so even if there is O2 in the headspace, the beer can't use it as there is CO2 sitting directly on top of the beer.
4 - if using a half full keg; or worried about a lack of seal from low pressure; I could always send some filtered 'air' into keg under pressure to seal, and then there is still O2 available for conditioning. AND there the vessel is pressurised so any production of CO2 from conditioning should go into solution.

more experience and time will tell whether these bits of theory stack up.
 
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It's all been discussed before.

http://aussiehomebrewer.com/topic/42436-oops-forgot-to-purge-keg-before-beer-went-in/page-2

If you do number 4 you might as well just tip your beer into the gutter imo.

4 - if using a half full keg; or worried about a lack of seal from low pressure; I could always send some filtered 'air' into keg under pressure to seal, and then there is still O2 available for conditioning. AND there the vessel is pressurised so any production of CO2 from conditioning should go into solution.
 

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Looking at the OP's linked KegKing chart, what's with the insistence that beer be refrigerated to 5c max?

Is there really no hope for people that brew proper beer and would like to taste it?
 

GalBrew

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Ok, you really have to get the idea of pumping any sort of gas that contains oxygen (ie. Air) into your fermented beer. It is going to ruin it, you can argue as much as you like, but you will oxidise your beer and it will taste like ass. How much O2 do you think is in the headspace of the average beer bottle used for conditioning? Not a hell of a lot, remember your yeast don't need a second growth phase they just need to ferment the tiny amount of priming sugar you add to your keg. Even if you filtered the beer, enough yeast would remain to facilitate this.

Can you even find another source of info anywhere on Earth that suggests pumping oxygen into beer? If you look at the ads for the picnic keg pump, which pumps the beer with air it will clearly state that this will reduce the life of your beer to a couple of days tops.
 

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