I fill a few bottles from a keg every batch to give away to people, and last week my brother in law commented that my bottles don’t hiss when opened. He thought they were under-carbonated. I have noticed the lack of a hiss, too, although the beer seems to me to be well carbonated and forms a nice head.
My process is to lower the pressure regulator to ~4 psi and then vent the keg. I use a beer gun with a 10’ hose on it. I purge each bottle with CO2 and then fill slowly until the liquid level reaches up into the neck. At that point I start withdrawing the beer gun slowly and keep going until there is foam coming out the top of the bottle with the beer gun completely removed. Then I cap the bottle. After the foam settles down the head space varies from 1/2" to 1".
I don’t see any way to pressurize the head space so it makes that satisfying hiss when the bottle is opened. Does it really matter?
Not to me. As long as the beer pours well with a proper head, I’d be happy. I do something similar when taking beer to meetings or giving beer to friends. I use plastic bottles (heavy plastic works best) to fill right from the kegerator tap. I clear the line a bit (and drink it!), disconnect the gas, release pressure and fill the bottle. Works just fine for short term storage.
The only real way to do it I can think of is to have the beer very slightly overcarbed when taking it to bottle. (Breweries will do this when canning as well).
Does it matter? To me and Boss, probably not, but both you and your brother in law noticed it and it impacted your impression of the beer. If it impacts your enjoyment, then yes, it matters to you! Now the question - is just where it lies on the cost/benefit curve for your enjoyment!
I use a TapCooler counter pressure filler to fill bottles of carbonated beer for homebrew meetings and to give to the SIL to take home. I simply match the counterflow pressure to my gauge carb pressure, purge the bottle and fill slowly. I use flip top bottles for meetings and always get the pop when I open the bottle. The sound gets a round of cheers at the meeting. This does add to the experience of the beer but is only good for short term (IMO only hours).
For longer term storage such as competitions and bottle aging, I bottle condition. I want the longer term effects of yeast scavenging and more precise control of v/v CO2. For this I closed xfer to keg as always and cold crash under 1-2 psi CO2 to flocculate undesirables and yeast for 3 days. I make a stock bottling solution by carefully measuring dextrose and cask conditioning yeast then add a specific volume to individual sanitized bottles to get the desired level of CO2. I usually use the high end of the carbonation range of the style for the calculations. I purge the bottle w/ 10 psi CO2 and counter pressure fill w/ uncarbonated beer in the keg at 10 psi. I cap w/ O2 barrier caps, check each with a Go-No Go gauge, place them in a box noting the bottling date, and place them back in my fermentation fridge for a controlled temperature environment to re-ferment in the bottle for ~ 2 weeks. After 2 weeks I place the box on a shelf in the basement. This all but eliminates oxidation, creates a nice foam for the judge, and definitely gives the pfffst when a bottle is opened.
It is all a matter of what affects your enjoyment of the beer bottled out of the keg. If the carbonation feels right on your palate when you drink it out of the bottle, it doesn’t hiss when opened, and doesn’t taste flat, you are probably OK. But it all depends on what you want esoterically.
That said, I normally serve my beers out of the keg at 10 PSI and around 40 degrees. When I bottle for a competition, I turn the keg pressure up to 15 PSI the night before I bottle, the beer. I then depressurize the keg and return the pressure gauge to 8-10 PSI when filling the bottles with a beer gun. This gives me the head I desire and the carbonation I need for competition beers that may sit for a couple weeks before being judged. Most of the time these bottles hiss when opened, but sometimes they don’t. I have never received a comment from a judge concerning under carbonation at a competition regardless of the lack of a hiss when the beer is opened.
The only caveat is that sometimes it takes a few days to get the keg pressure right again to balance the system after doing this, but I have learned to deal with it.
You may want to experiment with this idea when bottling, but the choice is yours. Also, as Dwain mentioned, bottle conditioning is also an option.
Good luck!
Thanks for the suggestions. I think I will try goose’s approach first and see how it works. I have bottle conditioned many times in the past, so I know how to do it, but it requires a big detour from my current process.
One advantage of trying this out to compare with other methods is that it can be inserted into the kegging workflow fairly painlessly. I see that Lallemand sells a cask conditioning yeast and “The recommended inoculation rate is 2 grams per 5 gallons, or approximately 1/2 tsp.” So basically is that several grains per bottle?
This is why I make a stock solution and use a syringe. Much easier to measure .35 grams yeast into 6 ml water add it to 30+ grams of dextrose dissolved in 5x times its weight in water. I stir the solution, pull the desired amount, fill the bottle, and repeat until my comp bottles are filled. The Lallemand calculator gives me the numbers for the volume of desired CO2.
It depends on the headspace. If there’s a big one, then gas pressure can build and hiss when the cap is removed. If there’s little or no headspace, there’s nowhere for the pressure to build, it all goes into solution in the beer. This doesn’t affect the carbonation or head on the beer since the hiss is just wasted gas. I’m for as small a headspace as possible as reduced the amount of oxygen the yeast needs to deal with.
I don’t bottle from kegs, but the principle’s the same.
Has anybody ever poured half a bottle, recorked the bottle and then opened it the following day? There’s always a massive hiss and the beer is less fizzy.
The question for me is not whether there is enough yeast but the condition and capability of the residual yeast.
IMO, the residual yeast are near the end of their life cycle. Also, this population of yeast comprises mixed-generations. Assuming fermentation began with 1st generation yeast, the generations will range from 3rd to 6th, and more than half will have gone into stationary and senescent states. If the yeast used in the fermentation were from a re-pitched source, the generational age can be up to 25 generations.
So, through chronological and generational mathematics, the pool of vigorous and active yeast is low. Such yeast are ill-equipped to function in the toxic environment of high gravity, high alcohol, high CO2, and low pH. In this environment, sugar uptake, CO2 generation, flocculation, and oxidative and stability assurances are all compromised.
I add Cask Conditioning yeast because it is adapted to the harsher environment and forms a very tight mat in the bottom of the bottle after the referment. I use dextrose because it’s a monosaccharide making it easier on the yeast to metabolize. Both are very cheap based on the small amounts I use. I believe it is very cheap insurance.
Of course, this is all my opinion based on research and conversations — your mileage may vary. However, I have uncontrolled feedback that this is a success: 3x 1st Place, 3x 2nd Place, and 1x 3rd Place since I began this process on my competition beers in Jan ‘25. I only bottle for competition, I force carb and consume the remaining beer. Who knows if these beers would have been just as successful without the process but I am very pleased w/ the outcome using it.
Dwain,
I am sure you are 100% correct, but I never gave it a thought because it seemed like a small effect. I am considering an experiment with a keg that I have had in the fridge for a month now, with fully-carbonated and very clear beer. I will be filling 6+ bottles, and I plan to add a small amount of sugar and a tiny bit of yeast at bottling time, about 1/10 the sugar that would be needed for full bottle conditioning. The idea is to just bump up the carbonation a bit and pressurize the head space. I will make up a syrup and add ~1/2 tsp to each bottle. After a month in the keg I am not sure about any remaining yeast so I will add a tiny amount just to be sure. It might work, and I don’t think it can do any harm.
I just calculated adding 10% more sugar. It resulted in increasing the volumes from 2.65 to 2.84. You might get a larger increase than you expected, so it’s probably worth doing the calculation for your situation.
Thanks. That sounds good for a first try. I want to exaggerate the effect on the first attempt so the result will be clearly detectable. After that I can dial it back as needed.
Bottle conditioning aside - if you use either of the two preferred methods for bottling off the keg (counter pressure or beer gun), once the pressure in the headspace equalizes, you are going to lose carbonation from how it tasted and poured from your keg. I would say that, per style, that almost 75% of all the beers that we judge for our competitions are under carbonated. As others have said, if you have “too little” of a headspace, then you won’t get the PSSST, which is desirable and indicative of correct packaging techniques. I would just follow Goose’s recommendation to increase the head pressure on the keg about 10-15%. I usually go from my “standard” 12PSI to 14PSI. Note that you have to keep that additional pressure on for several days before (maybe even a week) in order for the beer in the keg to equalize. Whether or not you go down to 10PSI or so for bottling is based upon your “beer gun vs. CPF” decision. I found beer guns to be fiddly, and require a really long hose to prevent foaming. I prefer a CPF. I can bottle at the same pressure that my keg is equalized to. I get no foaming if I don’t allow the beer to fill the bottle too quickly.
I think An Ankou is correct. It is entirely dependent on the headspace. All of the other posts are irrelevant (if interesting). The PFFFT sound is the pressurized gas escaping from the.headspace. If you fill the bottle too far it is still carbonated but it won’t make a PFFFT - not enough gas. This is a very easy experiment. Also, check out the headspace on commercial brews and try to match that. It’s easy to do with a beer gun.
I did a couple of experiments on bottle conditioning. I took beer from a keg that had been in the fridge for a month and added a bit of sugar to one, and sugar and yeast to others and left a control with no yeast or sugar, then bottled using my beer gun. I opened the first one yesterday, with only sugar added. It made a nice PFFFT when I opened it, and it didn’t seem over-carbonated. I was reminded of the downside of bottle conditioning though: the need to pour carefully to avoid getting the yeast from the bottom of the bottle.
Since I bottle beer to give away and I have no control over how the beer is stored and poured after I give it away, I decided I don’t want to give away bottle-conditioned beer that requires special attention. I don’t want someone getting a mouthful of yeast and thinking that is the way the beer was made to taste. I will be getting a counter pressure bottle filler soon so I can give that a try.
