Force Carbing And Increased Bitterness.

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What a load of rubbish Dr K.
You may well be correct browndog, but having re-read my post , on the whole I find, to my understanding no factual error, of course as my father often pointed out a fact is a small thing on the back of a flea.
I am always willing to learn so..for the benefit of the readers, you might point out the particular rubbish that makes (or made) up my load.

K
 
but you should never increase the pressure above serving pressure at your serving temp

Lies!
I force carbed a keg at 300kPa this afternoon and was pouring it at 70kPa 15 mins later. Why shouldn't I have done that?
 
Just as turning your oven thermostat to 250C is not going to get your oven to 170C any quicker than just setting 170, beer is just not going to get carbonated quicker at a higher pressure, put simply its a function of temperature (colder more gas dissolves) and time. Sure you speed things up by rolling or shaking or rattling the keg but you should never increase the pressure above serving pressure at your serving temp.
RDWHAHB

K

So you're saying that when i have two kegs of flat beer sitting at 3 degrees, hook one up to a reg at 80 kpa and the other to a separate reg at 300 kpa then both beers will reach a pressure of 80 kpa at the same time?

i would have thought that this is in fact different to an oven thermostat, so the keg being charged at 300 kpa reaches 80 kpa much quicker, like adding another heating element to one of the ovens instead of just setting the dial to 250 degrees.

please correct me if i'm wrong.
 
If there was a prize for over-complicating shit and then being vocal about the resulting failure, you'd be on the top of the podium, Truman.

Just do it like everyone else does it. FFS.
 
Lies!
I force carbed a keg at 300kPa this afternoon and was pouring it at 70kPa 15 mins later. Why shouldn't I have done that?
No reason why you should not have done so, and of course you did. The more inquisitive reader might ask how you read the equivalent pressure from carbonation in your glass...
K
 
As florian has stated, pressure does affect the time at a constant temperature , but the statement " you should never increase the pressure above the serving the serving pressure at your serving temp" is a bit strange, what will force carbonating do to the beer that carbonating at serving pressure won't?

-browndog
 
So you're saying that when i have two kegs of flat beer sitting at 3 degrees, hook one up to a reg at 80 kpa and the other to a separate reg at 300 kpa then both beers will reach a pressure of 80 kpa at the same time?

i would have thought that this is in fact different to an oven thermostat, so the keg being charged at 300 kpa reaches 80 kpa much quicker, like adding another heating element to one of the ovens instead of just setting the dial to 250 degrees.

please correct me if i'm wrong.
To the first question....yes (of course the keg at 300 will have pressure in it, as it would were it void of beer)
To the following (from the question) statement....heat is somewhat different from pressure
 
. . .
I am always willing to learn so..for the benefit of the readers, you might point out the particular rubbish that makes (or made) up my load.

:icon_offtopic: Or nearly so anyway. At least it contributes very little to the original question.

Dr K

Snipped from IBD material on gas transfer into beer - you might note that the rate of transfer of gas into liquid depends on an equation that has the equilibrium concentration on its top line. The equilibrium concentration is higher for a given temperature, at a higher headspace/gas pressure. So - the higher the pressure, the bigger the difference between the current concentration of CO2 in solution and the equilibrium concentration and therefore the higher the rate at which CO2 will go into solution. ie: Increasing the pressure will speed up carbonation.

And therein lies your load - unless its just me adding my load, in which case I have no doubt some kind soul will point that out too and we'll both be unburdened.

The Institute of Brewing and Distilling said:
Transfer of Gases into Solution

As seen previously, Dalton’s Law describes how, under equilibrium conditions,
a gas will exert a partial pressure above the liquid proportional to its molar
fraction.
If the gas is in contact with beer at a pressure above its equilibrium pressure,
gas will pass from the gas phase (headspace) into the liquid phase at a rate
described by the equation:
dc/dt = kL * A * (CE – C) / V
where:
kL is the mass transfer coefficient
A is the interfacial gas: liquid area
CE is the equilibrium concentration
C is the concentration of the gas in solution at time t
V is the volume of the liquid (beer)
and dC/dt is the rate of change of concentration with time
The rate of gas solution into liquids has a number of implications with respect
to beer, notably carbonation, but also dispense of keg beer and avoiding air
pickup.

So what are the factors that will lead to rapid gas pickup into beer?
Or, what can make dC/dt large?

• Interfacial Area (A) - if the size of the bubbles injected is very small, then
the interfacial area will be large and the rate of transfer high. We will see
later how this can be achieved in practice by the choice of carbonation
equipment.
If the beer is in a tank or a keg, then it is the surface area of the beer that
will have an effect on gas pickup.
• Mass Transfer Coefficient (kL) - this can be increased by having highly
turbulent flow at the gas injection point.
• Volume of Beer (V) - if the volume of beer is small, the rate of increase of
dissolved gas concentration will be faster. This is seen in dispense of keg
beer. As the volume of beer in the keg decreases, there is a rapid increase
in the ratio A/V and carbonation can quickly reach the equilibrium level
determined by the applied dispense pressure.
• Concentration Gradient (CE/C) - the further the carbonation level is from
equilibrium, the faster will be the transfer rate. We will see later how this
can also be affected by temperature and pressure.
 
If there was a prize for over-complicating shit and then being vocal about the resulting failure, you'd be on the top of the podium, Truman.

Just do it like everyone else does it. FFS.

I havent overcomplicated anything Nick. My original question was just simply does force carbing cause bitterness? It appears due to carbonic acid it does. It just happens that I made an error in force carbing which probably made things worse by reading the gauge wrong.

As for my force cabing method it was shown to me by a very experienced home brewer from here and works well. No different to what a lot of other Hbers on here do.

Add 300kpa to keg on day 1 and disconnect gas. Do the same 24 hours later, leave for a couple of days and check gas in keg and if below 100kpa add another 300kpa and disconnect gas. I cant leave my gas connected all the time as I dont have a hole through my fridge yet for the gas line.

Whats so over complicated about that???
 
I'm not convinced that the increased bitterness that you tasted is from your method of carbing - more I think it's just because your beer was "green" (as stux mentioned before)

.
It still doesnt seem carbed up properly now, not many bubbles in the beer and very little head. But does taste very bitter. So its the carbonic acid thats causing this? The word "TARTNESS" is certainly a good description of how it tastes.

You really need to have over carbed your beer to get noticeable carbonic bite, and believe me you'll know when you've done that.
 
I'm not convinced that the increased bitterness that you tasted is from your method of carbing - more I think it's just because your beer was "green" (as stux mentioned before)

.

You really need to have over carbed your beer to get noticeable carbonic bite, and believe me you'll know when you've done that.

Yeh well as I said there isnt much Co2 in the beer and a weak head so thats possible. Will just have to wait and see how it tatses in a week.
 
Truy originally asked if forced carbonation may have caused additional bitterness in his beer.

I'm not convinced that the increased bitterness that you tasted is from your method of carbing - more I think it's just because your beer was "green" (as stux mentioned before)

Ditto, while carbonic acid (H2CO3) concentration does alter mouthfeel and add a slight carbonic bite or sourness to beer. The method of dissolving Co2 has no influence that I have noticed. As for overcarbonation, have done this many times and never noticed a greater influence due to carbonic acid.

Green beer.....maybe
Infection.........maybe
Astringency........maybe
Overcarbonation.............meeeh!

Screwy
 
Truy originally asked if forced carbonation may have caused additional bitterness in his beer.



Ditto, while carbonic acid (H2CO3) concentration does alter mouthfeel and add a slight carbonic bite or sourness to beer. The method of dissolving Co2 has no influence that I have noticed. As for overcarbonation, have done this many times and never noticed a greater influence due to carbonic acid.

Green beer.....maybe
Infection.........maybe
Astringency........maybe
Overcarbonation.............meeeh!

Screwy

Thanks Screwy, hopefully its green beer. Doesnt smell funny so I hope its not infection. I did get some small particles of grain through the false bottom and into the kettle at mash out but only a small amount, hopefully not enough to cause any astringency. This was a pale ale so no dark grains used.
 
I cant leave my gas connected all the time as I dont have a hole through my fridge yet for the gas line.

You leave your fridge open while force carbing? Does the keg warm up at all?
 
Dare i be an idiot and ask what the style and IBU's of the beer was itended to be, or what type of hops were used in the beer?

How old is the beer? ie how many days out of secondary?

Also, were the hops of the same AA as your recipe was designed around or were the scales even accurate? Were the timing of each addition during the boil done at the right time as per the recipe.

A post mortem isn't always needed for a sore toe.

Also Truman, you can always stick the gas bottle into the fridge. Then it can stay connected.

It's always good to read the variations on how things are done on here, it's just a shame not all of the blokes respect the fact that there's more than 1 way to skin a cat and that their way is the only way.

For me, i stick most of my beers in the keg, purge a few times at 10psi (roughly 70kpa) whack it in the fridge and revisit it a month later when it's conditioned well and gassed right. Before the 4 week mark, i'd rather not bother and just drink something else. About the only exceptions are some of the wheat beers - where younger is generally better.

Just my unqualified opinions.

Martin
 
Dare i be an idiot and ask what the style and IBU's of the beer was itended to be, or what type of hops were used in the beer?

How old is the beer? ie how many days out of secondary?

Also, were the hops of the same AA as your recipe was designed around or were the scales even accurate? Were the timing of each addition during the boil done at the right time as per the recipe.

A post mortem isn't always needed for a sore toe.

Also Truman, you can always stick the gas bottle into the fridge. Then it can stay connected.

It's always good to read the variations on how things are done on here, it's just a shame not all of the blokes respect the fact that there's more than 1 way to skin a cat and that their way is the only way.

For me, i stick most of my beers in the keg, purge a few times at 10psi (roughly 70kpa) whack it in the fridge and revisit it a month later when it's conditioned well and gassed right. Before the 4 week mark, i'd rather not bother and just drink something else. About the only exceptions are some of the wheat beers - where younger is generally better.

Just my unqualified opinions.

Martin

The style was a Pale Ale (The parched as bro pale ale from the recipe data base.) The Ibus were 30 and I used brewmate to get the IBUs correct as per my AA etc. if anything I was under 30 as I was 4 grams short of Galaxy which was the only hops used in the brew.
I cant put the gas bottle in the fridge as its a CO2 fire extinguisher that I have mounted upside down on the side of the fridge.

@Nick....Im going to assume your shit stiring as I know your not an idiot to ask such a dumb question..or are you???
 
Just as turning your oven thermostat to 250C is not going to get your oven to 170C any quicker than just setting 170, beer is just not going to get carbonated quicker at a higher pressure, put simply its a function of temperature (colder more gas dissolves) and time. Sure you speed things up by rolling or shaking or rattling the keg but you should never increase the pressure above serving pressure at your serving temp.
RDWHAHB

K

That's nonsense.

Turning your regulator up to 450kpa will carbonate your beer in 12 hrs. The problem is it'll probably over carb it.

carbonation is a function of pressure over time at a given temperature.

Edit: and TB has quite helpfully provided the function. Sweet :)

Your analogy is quite simply, wrong
 
Truman,

i have made 2 beers with galaxy now and to my tastes, they are almost undrinkable week #1 and 2 in the keg. I am not sure how many grams in the receipe you used. Bitter passionfruit is all i can taste. A few weeks in the keg is more to my taste.
Others i gave my beer to were having no problems with it, but to me it was super bitter/sour/overpowering.

3 weeks in an i was able to enjoy it, probably after it stales somewhat :p
Perhaps this is a factor too?

Cheers,
D80
 
Truman,

i have made 2 beers with galaxy now and to my tastes, they are almost undrinkable week #1 and 2 in the keg. I am not sure how many grams in the receipe you used. Bitter passionfruit is all i can taste. A few weeks in the keg is more to my taste.
Others i gave my beer to were having no problems with it, but to me it was super bitter/sour/overpowering.

3 weeks in an i was able to enjoy it, probably after it stales somewhat :p
Perhaps this is a factor too?

Cheers,
D80

Diesel,

I know what your saying about Galaxy as Ive done a few brews using galaxy as well and in the bottle have had to wait 3-4 weeks for it to get better. But this bitter taste was not what I usually associate with galaxy. More like a tartness and similar to when you taste hot wort and its still very bitter. Ive never kegged a galaxy brew though, spose I will just have to give it some time.

Cheers
 
Diesel,

I know what your saying about Galaxy as Ive done a few brews using galaxy as well and in the bottle have had to wait 3-4 weeks for it to get better. But this bitter taste was not what I usually associate with galaxy. More like a tartness and similar to when you taste hot wort and its still very bitter. Ive never kegged a galaxy brew though, spose I will just have to give it some time.

Cheers

Well on the bright side (pun intended) you won't have to wait as long with a kegged beer compared to a bottled beer.....
 
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