Yes, active as in present and alive. Yep, I would say that when the pressure stops dropping the beer should be fully carbed which should take about 2-3 weeks under normal circumstances. I've never had a beer fail to carbonate in the bottle and only rarely has any been fully carbonated in less than two weeks. Again, putting a gauge on a bottle would be interesting to observe, but that's about all it would be for me.
Pressure gauge mounted in bottle cap
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Yes, active as in present and alive. Yep, I would say that when the pressure stops dropping the beer should be fully carbed which should take about 2-3 weeks under normal circumstances. I've never had a beer fail to carbonate in the bottle and only rarely has any been fully carbonated in less than two weeks. Again, putting a gauge on a bottle would be interesting to observe, but that's about all it would be for me.
OP
OP
Equilibrium is the result of diffusion.
OP
OP
Dropped it in the fridge tonight. We'll see what it looks like in the AM
OP
OP
Removed from fridge this morning.
After 12 hours in fridge:
After sitting on my den workbench all day:
After 12 hours in fridge:
After sitting on my den workbench all day:
OP
OP
Alright, I put it back into the fridge, chilled, and served.
It was not fully carbonated. The body did have some moderate carbonation, but there was not enough there to lift a head on the pour.
The good news is that my octoberfest is EXCELLENT! I'm pretty happy about this because I donated a keg of it to a local festival on Saturday.
This has been an interesting experiment in understanding the way CO2 is created and absorbed by the yeast & beer. I intend on doing this with every batch I bottle. I'll be more patient with the next batch.
Cheers!
It was not fully carbonated. The body did have some moderate carbonation, but there was not enough there to lift a head on the pour.
The good news is that my octoberfest is EXCELLENT! I'm pretty happy about this because I donated a keg of it to a local festival on Saturday.
This has been an interesting experiment in understanding the way CO2 is created and absorbed by the yeast & beer. I intend on doing this with every batch I bottle. I'll be more patient with the next batch.
Cheers!
![Craft A Brew - Safale BE-256 Yeast - Fermentis - Belgian Ale Dry Yeast - For Belgian & Strong Ales - Ingredients for Home Brewing - Beer Making Supplies - [3 Pack]](https://m.media-amazon.com/images/I/51bcKEwQmWL._SL500_.jpg)
kenc_zymurgy
Well-Known Member
Very interesting.
If I understand this correctly, it seems that in some cases yeast can produce CO2 faster than the beer will absorb it. Many of us bottle a sample in a PET bottle to monitor carbonation - so this can tell us that the yeast is working, but it could take a bit longer for that CO2 to fully carbonate the beer. That seems to match my experiences also, when I notice that the bottle gets firm within a few days, but after a week, the carbonation does not seem complete. But a week later it is much better.
Related questions:
If a sealed beer has stabilized at room temperature and high pressure (say 68F, 28PSI = 2.5 volumes), and it is quickly chilled to 36F, should we expect to see the pressure (still sealed - no external CO2 feed) reduce to 10 PSI (the same 2.5 volumes @ 36F)? And does it take any time for this to settle in (assuming the temperature has stabilized)? I don't think there is any CO2 moving between the head space and the beer - in each case the pressure/volumes are stable, right? So I don't think it should take any time. And I don't think the amount of head space should affect this either. But I don't know for sure.
My experience with mini-kegs with a tap set-up (where I can easily measure the pressure) seems to follow this, the pressure drop from room (naturally or force carbed) to chilled follows the charts.
-kenc
If I understand this correctly, it seems that in some cases yeast can produce CO2 faster than the beer will absorb it. Many of us bottle a sample in a PET bottle to monitor carbonation - so this can tell us that the yeast is working, but it could take a bit longer for that CO2 to fully carbonate the beer. That seems to match my experiences also, when I notice that the bottle gets firm within a few days, but after a week, the carbonation does not seem complete. But a week later it is much better.
Related questions:
If a sealed beer has stabilized at room temperature and high pressure (say 68F, 28PSI = 2.5 volumes), and it is quickly chilled to 36F, should we expect to see the pressure (still sealed - no external CO2 feed) reduce to 10 PSI (the same 2.5 volumes @ 36F)? And does it take any time for this to settle in (assuming the temperature has stabilized)? I don't think there is any CO2 moving between the head space and the beer - in each case the pressure/volumes are stable, right? So I don't think it should take any time. And I don't think the amount of head space should affect this either. But I don't know for sure.
My experience with mini-kegs with a tap set-up (where I can easily measure the pressure) seems to follow this, the pressure drop from room (naturally or force carbed) to chilled follows the charts.
-kenc
Interesting thread.
Found this:
http://www.deep-six.com/page70.htm
Strangely it's written for scuba divers, but answers a lot of questions about pressure, temp and transfer of gas to and from liquids.
In particular:
""Henry's law: A gas over a liquid will flow into the liquid until the pressure is equal. If you covered a lake with neon, the atoms of that gas would pass though the surface of the water until the neon in the water had the same pressure as what is left in the air. ""
Found this:
http://www.deep-six.com/page70.htm
Strangely it's written for scuba divers, but answers a lot of questions about pressure, temp and transfer of gas to and from liquids.
In particular:
""Henry's law: A gas over a liquid will flow into the liquid until the pressure is equal. If you covered a lake with neon, the atoms of that gas would pass though the surface of the water until the neon in the water had the same pressure as what is left in the air. ""
Sorry for bringing this thread back to life but I think it's worth talking about more. It seems that quite a few people think that a yeast-initiated carbonation in the bottle causes the headspace to pressurize with more CO2 molecules than are initially dissolved in the beer from the metabolism of the sugars. I think this is an issue of mixing concepts we learn from the application of external CO2 in a force carbonation situation.
First, keep in mind that in a closed system of liquid and co2, the concentration of CO2 will always seek equilibrium. The transfer from an area of higher concentration to lower is a result of diffusion. Yes, I do agree that the process can take a little time (dependent on a couple different factors).
In a force carb situation, the concentration of CO2 in the beer is generally low (it depends on what temperature the beer was fermented at as well as what temperature it was subsequently warmed to while still in an open container (airlocks count since gas can escape).
Think of it this way: The beer is essentially generating CO2 in the carboy and it has to push against the ambient atmosphere to escape through the airlock. At sea level, that's about 14psi. If you fermented the beer at a rock solid 70F, when fermentation is done, the dissolved CO2 is approximately .7 volumes before you do anything else. In other words, as it was fermenting, the beer AND the headspace were sitting at 14psi or 1ATM and .7 volumes of CO2 cannot escape from the beer. In reality, the concentration in the beer will be a bit higher than the headspace because it's actively being generated and that's why a bubble forms and rises to the surface. When fermentation is over, eventually all the excess CO2 in the beer will equalized to the headspace resulting in .7 volumes dissolved.
Now you take that beer, transfer it to a bottle, add sugar, and seal the cap. Now the ambient 1ATM of pressure is irrelevant. We're in a closed system. As yeast metabolize the sugar and create CO2, the concentration of CO2 in the beer is immediately higher than that of the headspace, let's say .8 volumes... diffusion is about to make the headpace equal and so on. In no way would the headspace ever have a higher concentration of CO2 than the beer in which it originated. The yeast don't swim to the surface to fart.
One last side note that isn't really on topic, but perhaps interesting anyway. If you have a beer in a carboy that is done actively fermenting, the CO2 concentration in the beer and in the headspace will eventually equilibrate to the concentration of CO2 in the area it's sitting in. For all intents and purposes, it's the concentration of earth's atmosphere (.0387% by volume). This sort of blows people's minds because you think, how can CO2 get past the water in the airlock? It diffuses into the water, then it diffuses out on the other side. Oxygen and nitrogen do the same thing in the opposite direction. The water just slows it down.
First, keep in mind that in a closed system of liquid and co2, the concentration of CO2 will always seek equilibrium. The transfer from an area of higher concentration to lower is a result of diffusion. Yes, I do agree that the process can take a little time (dependent on a couple different factors).
In a force carb situation, the concentration of CO2 in the beer is generally low (it depends on what temperature the beer was fermented at as well as what temperature it was subsequently warmed to while still in an open container (airlocks count since gas can escape).
Think of it this way: The beer is essentially generating CO2 in the carboy and it has to push against the ambient atmosphere to escape through the airlock. At sea level, that's about 14psi. If you fermented the beer at a rock solid 70F, when fermentation is done, the dissolved CO2 is approximately .7 volumes before you do anything else. In other words, as it was fermenting, the beer AND the headspace were sitting at 14psi or 1ATM and .7 volumes of CO2 cannot escape from the beer. In reality, the concentration in the beer will be a bit higher than the headspace because it's actively being generated and that's why a bubble forms and rises to the surface. When fermentation is over, eventually all the excess CO2 in the beer will equalized to the headspace resulting in .7 volumes dissolved.
Now you take that beer, transfer it to a bottle, add sugar, and seal the cap. Now the ambient 1ATM of pressure is irrelevant. We're in a closed system. As yeast metabolize the sugar and create CO2, the concentration of CO2 in the beer is immediately higher than that of the headspace, let's say .8 volumes... diffusion is about to make the headpace equal and so on. In no way would the headspace ever have a higher concentration of CO2 than the beer in which it originated. The yeast don't swim to the surface to fart.
One last side note that isn't really on topic, but perhaps interesting anyway. If you have a beer in a carboy that is done actively fermenting, the CO2 concentration in the beer and in the headspace will eventually equilibrate to the concentration of CO2 in the area it's sitting in. For all intents and purposes, it's the concentration of earth's atmosphere (.0387% by volume). This sort of blows people's minds because you think, how can CO2 get past the water in the airlock? It diffuses into the water, then it diffuses out on the other side. Oxygen and nitrogen do the same thing in the opposite direction. The water just slows it down.
Ever since I switched to 1/2 liter swing-top bottles, I've been having trouble with over carbonation and gushering, even after 2months in the bottle.I'm beginning to think I'm not leaving enough head space. With 12 oz. bottles, I would just use the displacement of the bottling wand to set the correct headspace. Does that work with larger bottles or should I leave a bit more?
Clementine
Well-Known Member
I agree with what Bobby says here I was discussing why bottled conditioned beer takes longer to than just the time for the yeast to consume the sugar to be properly carbonated and have nice fine bubbles. Everyone seems to think that it was the CO2 dissolving into the beer from the head space, my opinion is that as the beer is allowed to settle and the yeast and sediment in the beer drop from solution that their is less nucleation sites for the CO2 to come out of solution and hence a finer bubble. The CO2 is excreted by the yeast into solution one molecule at a time the excess dissolved beer is off gassed into the head space.
CO2 in the head space of a carboy vs CO2 in the beer is extremely complicated when you look at the law of partial pressures and the affect of gasses exchanging through the water/alcohol in the air lock and the back pressure of gasses caused by the airlock it is enough to make you go crazy. This effects your carbonation level as the dissolved CO2 concentration is added to your total CO2 in most priming calculators.
If you ever want to see the law of partial pressures in action get one of those stupid pump caps that someone thought would allow you to keep soda carbonated by pumping atmospheric air into the head space of a opened soda bottle.
http://www.amazon.com/dp/B00004XSH3/?tag=skimlinks_replacement-20
It does not take into account that air is only 1% CO2, when I saw those in the super market I thought that was so funny, it was a tax for those people who were not listening in chemistry class.
Head space to beer ratio matters, I think the less head space the better as then you have less O2 in the beer during the bottling process but back off your sugar to get the desired results. All the pressure in the bottle is equal through out liquid and gas, if your head space is the same volume (determined by the bottle wand) and you are producing the same amount of CO2 your pressure will be higher.
Think of it like this 12oz bottle = 12 oz of beer with a set amount of sugar produces X volumes of CO2. 24oz of beer with the same concentration of priming sugar with produce 2X volumes of CO2. Now the head space has stayed the same so the ratio has been increased resulting in higher pressure. It is a lot more complicated than that as you have to throw in there how much space the water (beer) molecules take up so that will further skew the pressure relationship, throw in temp changes effecting the CO2 solution and it is really complicated. I don't know of a priming calculator for different size bottles but I would start with backing off the sugar concentration by 5 to 10% to start with and see how it goes. I enjoy my beer on the lower side of the carbonation style so I would rather under shoot than over shoot.
Clem
CO2 in the head space of a carboy vs CO2 in the beer is extremely complicated when you look at the law of partial pressures and the affect of gasses exchanging through the water/alcohol in the air lock and the back pressure of gasses caused by the airlock it is enough to make you go crazy. This effects your carbonation level as the dissolved CO2 concentration is added to your total CO2 in most priming calculators.
If you ever want to see the law of partial pressures in action get one of those stupid pump caps that someone thought would allow you to keep soda carbonated by pumping atmospheric air into the head space of a opened soda bottle.
http://www.amazon.com/dp/B00004XSH3/?tag=skimlinks_replacement-20
It does not take into account that air is only 1% CO2, when I saw those in the super market I thought that was so funny, it was a tax for those people who were not listening in chemistry class.
Head space to beer ratio matters, I think the less head space the better as then you have less O2 in the beer during the bottling process but back off your sugar to get the desired results. All the pressure in the bottle is equal through out liquid and gas, if your head space is the same volume (determined by the bottle wand) and you are producing the same amount of CO2 your pressure will be higher.
Think of it like this 12oz bottle = 12 oz of beer with a set amount of sugar produces X volumes of CO2. 24oz of beer with the same concentration of priming sugar with produce 2X volumes of CO2. Now the head space has stayed the same so the ratio has been increased resulting in higher pressure. It is a lot more complicated than that as you have to throw in there how much space the water (beer) molecules take up so that will further skew the pressure relationship, throw in temp changes effecting the CO2 solution and it is really complicated. I don't know of a priming calculator for different size bottles but I would start with backing off the sugar concentration by 5 to 10% to start with and see how it goes. I enjoy my beer on the lower side of the carbonation style so I would rather under shoot than over shoot.
Clem
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I don't claim to know the science, but didn't someone here put a pressure gauge on a bottle and record the pressure during the carbonation process at a constant temperature? What I thought I read is that the pressure peaked and then dropped.
My conclusion from this would be that it is similar to pumping CO2 in through your out tube in a keg. You don't get much benefit from it because the CO2 first rises to the head space and then reaches equilibrium over time. I'd think that naturally carbonating is the same. The yeast consumes sugars and produces CO2 which goes into the head space and raises the pressure there. Over time it comes into equilibrium with the fluid.
The yeast don't swim to the surface and fart. It's more farting in the bath tub. The first thing it does it bubble up to the surface and stink up the room.
But this is me being an armchair scientist. It could be like Bobby say. That the CO2 is absorbed as quickly as it is produced.
It sounds like a good timelapse experiment to me. The most important thing to me is making sure that temperature variations are not affecting the pressure. The way to do it would be to run thermowell and log temps along with pressure.
I think the most non-intuitive part of this thing is thinking at a molecular level. We often visualize CO2 in terms of bubbles. In order for a CO2 bubble to form, the pressure differential has to be pretty significant. If you bottle a light/clear beer in a clear glass bottle, you won't ever see bubbles.
I think the most non-intuitive part of this thing is thinking at a molecular level. We often visualize CO2 in terms of bubbles. In order for a CO2 bubble to form, the pressure differential has to be pretty significant. If you bottle a light/clear beer in a clear glass bottle, you won't ever see bubbles.
alchemedes
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After reading this thread I am still confused Would the mounted psi gauge on top of the bottle not be a great way to monitor the pressure exerted on the bottle from within during the fermentation phase?
I am thinking this would be a simple way to monitor pressure when doing batches of ginger beer in PET bottles, that is, wait 'til the guage reads 40-50 psi and then you know it's time for a cold crash vs the old 'squeeze it and see how hard it is method.' :cross: Am I right thinking along these lines, or did I miss something?
Would the mounted psi gauge on top of the bottle not be a great way to monitor the pressure exerted on the bottle from within during the fermentation phase? I am thinking this would be a simple way to monitor pressure when doing batches of ginger beer in PET bottles, that is, wait 'til the guage reads 40-50 psi and then you know it's time for a cold crash vs the old 'squeeze it and see how hard it is method.' :cross: Am I right thinking along these lines, or did I miss something?
JuanMoore
Getting the banned back together
I don't think that's quite correct. Even in a closed system there can be a substantial difference in CO2 distribution. Take a bottle or can of soda and shake it up for a minute. The agitation will cause a lot of the CO2 to come out of solution and into the headspace, making the bottle/can much more firm from the additional pressure. The greater internal pressure relative to atmospheric pressure is what causes it to foam if opened before it has time to reabsorb the CO2.
I've never made ginger beer, but it sounds like a good plan to me.
JuanMoore
Getting the banned back together
From another thread here-
Even though there's no temp log, the person who posted this mentioned that it was in a home with the thermostat set to a low of 65° and a high of 72°. The daily temp fluctuations are fairly obvious, but it's hard to know how much the temp was really changing. The difference in pressure between 65° and 72° would be ~3.5 psi, but the difference between the peak and where the pressure settled appears to be closer to 6 psi. Unless the bottle developed a tiny leak, there was more going on to create that rise and fall trend than simply temperature fluctuations.
JuanMoore said:
Disagree. A bottle of sealed soda has co2 at equilibrium. Shaking does not pull co2 out of solution because it can't. The partial pressure in the headspace and the newly formed bubbles already matches that of the dissolved co2. The reason it gushes after shaking is that the bubbles create nucleation point similar to mentos in diet coke.
I peg the pressure spike on temperature. There are two factors that have not come up on that graph. The first is that fermentation is exothermic so the thermostat controlling ambient temps doesnt tell us enough. Also, there is plenty of variance in temps in a house well outside the thermostat range, e.g. drafts and radiant heat from windows. Last, spikes in temp are going to affect the headspace quicker due to the heat capacity difference from liquid.JuanMoore said:
Long story short, the experiment must be repeated with the bottle in a water bath with temp logging along with pressure. The results will probably change.
Hex23
Well-Known Member
How funny that I just read this tonight as I finish bottle conditioning another batch with this setup. I did use a water bath this time, but it had limited effect on the pressure fluctuations. I think the fact that I did not cover the headspace part of the bottle let that part continue to fluctuate temps. And unfortunately I did not record temps (again!) - there's always next time. I'll post the data later. I'm still a little perplexed about the apparent overshoot, then undershoot and recovery in the first data set. I still wonder if the absorption function is such that it creates a longer term ringing and settling. This would be more apparent if I passed the data through a filter to attenuate the 24 hour signal. I guess the absorption function is a mass transfer problem and can be mathematically pretty complicated. Of course that view is consistent with the idea that pressure forms faster in the headspace, then gets absorbed toward equilibrium. I feel like that view could be right because of the fact that the process of the gas coming out of solution is easier/faster than getting it back in.
Hex23
Well-Known Member
I did go on weather underground to get external temps for my area from that timeframe, but my recollection is that when I graphed them together with pressure there wasn't any obvious correlation. However, I agree that other phenomena (drafts, etc) could have contributed. Ultimately I need to measure ambient temps - and maybe do a better job controlling them.
Hex23
Well-Known Member
Here is the data from this batch. One procedural differences to highlight ... This time I switched to a wider bottling wand which left more headspace than last time (probably double the headspace as last time, about 2"). I'll probably go back to the narrower bottling wand b/c I don't like that much headspace.
Now some comments on the data. Near the beginning there is about 12 hours of missing data where the monitor crapped out. Think I know what happened and how to avoid it next time.
The initial pressure rise was really fast.
I don't really know why, but the pressures never really reached where I would have expected. I doubt it can be attributed to the increased head space. If the data is right then the CO2 in this bottle is about 1.5 volumes. I'll say that other bottles from this batch are properly carb'ed - definitely more than 1.5 volumes. I haven't cracked the monitoring bottle yet.
I do see some similar artifacts as last time (besides the 24 hour cycle) - looks like overshoot, then oscillations settling to a mean.
I'll also mention that today we did not have the AC on and local outdoor temps reached 80. That's the probable reason for the last spike.
Any thoughts on what I should do differently next time? I may have to put the bottle in my fermentation chamber to keep the temp more constant. This water bath was not a temp controlled bath - just more thermal mass to try to slow the swings and apparently wasn't very effective. I'll also see if I can get a temp recording. Would be cool to have a gravity reading too, but I can't imagine how to do that.
Now some comments on the data. Near the beginning there is about 12 hours of missing data where the monitor crapped out. Think I know what happened and how to avoid it next time.
The initial pressure rise was really fast.
I don't really know why, but the pressures never really reached where I would have expected. I doubt it can be attributed to the increased head space. If the data is right then the CO2 in this bottle is about 1.5 volumes. I'll say that other bottles from this batch are properly carb'ed - definitely more than 1.5 volumes. I haven't cracked the monitoring bottle yet.
I do see some similar artifacts as last time (besides the 24 hour cycle) - looks like overshoot, then oscillations settling to a mean.
I'll also mention that today we did not have the AC on and local outdoor temps reached 80. That's the probable reason for the last spike.
Any thoughts on what I should do differently next time? I may have to put the bottle in my fermentation chamber to keep the temp more constant. This water bath was not a temp controlled bath - just more thermal mass to try to slow the swings and apparently wasn't very effective. I'll also see if I can get a temp recording. Would be cool to have a gravity reading too, but I can't imagine how to do that.
ZackN
Well-Known Member
That looks like Logger Pro, what sensor are you using to read the pressure?
I think having an RTD in a thermowell inside the beer and logging those temps would be ideal. One thing I suspected could be happening is that your bottle seal, or the bulkhead you put in is only capable of holding 10 psi and any more than that, it tweaks the seal letting some gas escape. That would explain the oscillation if it is not directly correlated to beers temps. I don't know how exothermic this mild fermentation is.
Hex23
Well-Known Member
The sensor is off the shelf. It's a Dwyer 628CR with 0-50 PSI range. The logger is something I built with spare parts.
Hex23
Well-Known Member
I thought about this some more and tried another experiment. I used a couple of alka seltzer tablets and a small amount of water in the bottle to build pressure and test for leaks. The small amount of water was so that I wouldn't see much effect from CO2 being lost/dissolved back into the water. Some background: The cap I made uses a kork-n-seal resealable cap (see http://www.sha.org/bottle/closures.htm about midway down for a picture). I picked up some of these that were in excellent unused condition. I took this route b/c I wanted to use a glass bottle and a re-usable cap. Anyway, when I ran the leak experiment, it didn't seem like the pressure went as high as I would have predicted. When I picked up the bottle and placed pressure on the lever, I heard a hiss. I ran the experiment again and overnight the pressure dropped from about 15 PSI to 4 PSI. Definitely a leak existed. I examined the rubber seal and found that it was pretty compressed and had a slight amount of residue underneath it. I think it was the original seal in the bottle cap (prob circa 1960!). I replaced it with a new hose washer which is a slight bit thicker and made with more modern material. The lever now resists more and snaps into place. I started another experiment on this new cap and it's held 22 PSI for over 24 hours now.
I suspect the leak developed on the second batch and got even worse when I tried these leak experiments. I'm not sure about the first dataset. It seems like a leak would be more intermittent and faster. But anyway, no way telling until I run the priming experiment again. This time I'll pre-test the cap to 30 PSI and I might just switch to a plastic bottle/screwtop.
That shouldn't be too hard. But I would probably change to a PET bottle if the sensor had to be in the beer. However, I think it would be good enough to tape a sensor to the outside of the bottle and insulate it.
I would guess it's not very exothermic. I'd be surprised if it raised the temp by more than 1F.
Hex23
Well-Known Member
I guess I'm not really sure what I did back then
... but, I went back and graphed average outdoor temps vs pressure and there does appear to be some correlation. I still want to run the experiment with more temp control and recording just to see if this is all due to temps. I also filtered out the signal with 24 hr period in this data. 
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Shaking can pull it out of solution because nucleation (from energy input spent shaking) IS causing CO2 to escape from the liquid (evidenced by the bottle hardening) and it is not being replaced back into solution at the same rate, and therefore it is no longer in a state of equilibrium. Equilibrium doesn't imply that two things are equal, it just means that reactions going both directions are happening at the same rate. After shaking the bottle and causing CO2 to escape from solution, there is excess CO2 in the headspace above the liquid due to the energy put into shaking the bottle, and according to Le Chatelier's Principle, after the shaking has stopped (no more energy input on reactant's side), excess products on one side will cause the reaction to shift so that more reactants are created. Basically, CO2 will begin dissolving faster than it is escaping the liquid. But it still takes time for equilibrium to be established again. CO2 is CONSTANTLY seeping out of the liquid and being absorbed. In equilibrium, these rates are the same. When you put in energy (such as shaking), you are disrupting the equilibrium. This principle also explains the effect of temperature, because the K value changes with it.
EDIT: here's a picture
I'm not biting on this just yet. Have you ever put a pressure gauge on a sealed carbonated container, noted the pressure at stasis and then noted a pressure increase after shaking? If you haven't but know of a video or paper where it has been documented let me know.
http://www.phys.csuchico.edu/kagan/profdev/soda.pdf
I don't know why you would suggest that shaking in a closed system disrupts equilibrium. Le Châtelier's Principle requires that you change something like temperature, pressure or concentration. Shaking does none of this.
Hex23
Well-Known Member
OK, trial 3 is finally done. It turned out to be a pretty tasty beer too! (afterall, this really is still about making beer) It started as a Goose Island Mild Winter clone, but I decided to add a little more rye than normally recommended. I tastes nice, but I know I wouldn't add any more rye than I did.
Anyway about the experiment. I built an entirely new cap/bulkhead to try to eliminate the leak issue:
I pressure tested it to 49 PSI for about 2 days and it didn't appear to leak at all:
The priming was carried out in my fermentation chamber at around 70 F for 3 weeks. It does look like the pressure built to a plateau of 39 PSI and then diminished to settle at 35 PSI. The priming sugar amount should have put this at 2 volumes. At 72 F (as measured) that should have make a pressure of about 23 PSI at equilibrium. This is obviously well above that.
Anyway about the experiment. I built an entirely new cap/bulkhead to try to eliminate the leak issue:
I pressure tested it to 49 PSI for about 2 days and it didn't appear to leak at all:
The priming was carried out in my fermentation chamber at around 70 F for 3 weeks. It does look like the pressure built to a plateau of 39 PSI and then diminished to settle at 35 PSI. The priming sugar amount should have put this at 2 volumes. At 72 F (as measured) that should have make a pressure of about 23 PSI at equilibrium. This is obviously well above that.
OP
OP
very cool
