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*if naturally carbed.

A sugar primed keg, a spiesed keg and a spunded keg will not all be created equal. I have tested all 3. As Edelstoff says, the speise will be the best you can do for bottle carbonation. But a spunded keg is the holy grail.

The serving oxidation will be faster with ales than it will be with lagers. Lager yeast can produce much higher fermentation derived sulfites( about 10-30ppm), while ale yeast struggle to produce 5ppm. Those fermentation derived sulfites are you key to post fermentation freshness. Once those sulfites get used up, next up is your hop and malt phenols.

Right. I was commenting on this.... "Even if you naturally carbonate in the keg to avoid force carbonating; wouldn't putting it on gas for serving eventually introduce oxygen anyways?" ...... so I figured that part was assumed :D
 
Thanks for your reply. Sounds pretty easy but I will be honest that cold side LODO is just too much for me. I wish my inner beer nerd would take over but it just seems like work instead of a hobby. If I can't use bottled CO2 to at least augment some natural carbonation then it is a bridge too far. Maybe someday.

I think the thought with this after reading some of the replies since my last posting is that C02 CAN be used to serve, but you get the maximum LODO benefit from moving the beer to a keg with a few points to spare and letting it finish up in the serving keg (using a spunding rig as others have mentioned) so it scavanges the remaining oxygen picked up during x-fer to keg as well as naturally carbing the beer (which in my mind saves $$$ with CO2 cost).


This to me this is more about knowing when and where your beer is going to finish up and might be something I actually give a try with the octoberfest I have sitting about 5 days in the fermenter..

I still am of the mindset that keeping the beer in a fully sealed environment post boil is the best thing to do honestly for any beer (LODO or non-LODO) on the cold side and is my next big step with my beer.
 
I think the thought with this after reading some of the replies since my last posting is that C02 CAN be used to serve, but you get the maximum LODO benefit from moving the beer to a keg with a few points to spare and letting it finish up in the serving keg (using a spunding rig as others have mentioned) so it scavanges the remaining oxygen picked up during x-fer to keg as well as naturally carbing the beer (which in my mind saves $$$ with CO2 cost).


This to me this is more about knowing when and where your beer is going to finish up and might be something I actually give a try with the octoberfest I have sitting about 5 days in the fermenter..

I still am of the mindset that keeping the beer in a fully sealed environment post boil is the best thing to do honestly for any beer (LODO or non-LODO) on the cold side and is my next big step with my beer.

But even if you do naturally carb in the keg by whatever method, don't you *have* to serve with external CO2? Surely there isn't enough pressure retained from the spund to actually serve a whole keg (or anywhere near that).
 
But even if you do naturally carb in the keg by whatever method, don't you *have* to serve with external CO2? Surely there isn't enough pressure retained from the spund to actually serve a whole keg (or anywhere near that).

You do need external bottled CO2 to serve. The issue comes in when you use this bottled co2 to carbonate.

When CO2 makes the journey from the CO2 bottle to the keg, oxygen comes along for the ride and finds itself in the keg too. Force carbonation requires a larger amount of CO2 when compared to simply using the CO2 to serve an already carbonated beer. That means force carbonation also results in more oxygen in the keg.

The amount of oxygen exposure will also increase as the keg contents are depleted and more CO2 is pumped in.

I think everything I'm saying here is accurate. It took some noodle scratching for me to get there, so someone chime in if it's not making sense.
 
I think everything I'm saying here is accurate. It took some noodle scratching for me to get there, so someone chime in if it's not making sense.

This is how i was rationalizing it too and it seems simple. But, if i learned anything from engineering school it was that if a problem seems too simple, there's a very good chance you don't understand it well enough. :)

I think there may be more at play here such as solubility, partial pressures, diffusion and equilibrium.

I'm also thinking that it's not as much due to the impurity of forced carbonation that's the issue, rather it's the amount of air introduced during racking that contributes the excess oxygen. The natural carbonation process takes care of that air.

I am not stating any of the above as fact, just my thoughts. I would love to see a discussion that puts some numbers to these scenarios.
 
But a spunded keg is the holy grail.

Those fermentation derived sulfites are you key to post fermentation freshness. Once those sulfites get used up, next up is your hop and malt phenols.

But this cannot be a hard and fast rule for all beer styles? Most if not all lagers taste better with a little sulfur flavor, or tank taste as Brandon puts it. However in a lot of ale styles those same sulfury notes are out of place. Take for instance an American brown that I make often. Transferring too early to the keg traps some sulfur that takes forever to age out if at all. Conversely if I allow an additional week in contact with the yeast cake these off flavors are cleaned up and/or vented as opposed to being trapped by the spund. My kolsch brewed with 2565 also benefits from longer primary time. Thus my use of the method to restart the ferment after that resident time but before transfer.
Am I losing staling protection from the yeast derived sulfites? Most probably.. but then Kölsch isn't a beer that stores well anyway.
 
You do need external bottled CO2 to serve. The issue comes in when you use this bottled co2 to carbonate.

When CO2 makes the journey from the CO2 bottle to the keg, oxygen comes along for the ride and finds itself in the keg too. Force carbonation requires a larger amount of CO2 when compared to simply using the CO2 to serve an already carbonated beer. That means force carbonation also results in more oxygen in the keg.

The amount of oxygen exposure will also increase as the keg contents are depleted and more CO2 is pumped in.

I think everything I'm saying here is accurate. It took some noodle scratching for me to get there, so someone chime in if it's not making sense.

Correct.

If your beer finished fermentation with 0.85 vols of CO2, and you forced carbed to 2.5 vols, then that would require 2.5 - 0.85 = 1.65 vols of CO2 from the bottle. For 5 gal of beer that would be 8.25 gal at 14.7 psi absolute. To serve 5 gal at 12 psi gauge (26.7 psia) would require 5 gal * 26.7 psia / 14.7 psia = 9.08 gal at 14.7 psia. So, force carbonating exposes the beer to almost twice as much total O2 as naturally carbonating over the life of the keg. Different fermentation temperature (starting carb level), different final carb level (CO2 pressure & temp), and correcting for actual temp vs. 0˚C (STP) will change the numbers a little bit, but not change the basic conclusion.

Brew on :mug:
 
Correct.

If your beer finished fermentation with 0.85 vols of CO2, and you forced carbed to 2.5 vols, then that would require 2.5 - 0.85 = 1.65 vols of CO2 from the bottle. For 5 gal of beer that would be 8.25 gal at 14.7 psi absolute. To serve 5 gal at 12 psi gauge (26.7 psia) would require 5 gal * 26.7 psia / 14.7 psia = 9.08 gal at 14.7 psia. So, force carbonating exposes the beer to almost twice as much total O2 as naturally carbonating over the life of the keg. Different fermentation temperature (starting carb level), different final carb level (CO2 pressure & temp), and correcting for actual temp vs. 0˚C (STP) will change the numbers a little bit, but not change the basic conclusion.

Brew on :mug:

Good info..Still digesting all of this and adjusting each side of the brew as I go, but seeing how the numbers for this portion of the beer cycle makes this make better sense in my mind...
 
Natural carbonation in a keg is so simple to achieve i don't know why it's not more common. I suspect even if you didn't do hot side LoDO you'd still get a net benefit from this.

Make a mixture of 100g sugar and 100g water (actual amounts will vary based on target carbonation and current beer temp and pressure - use a priming sugar calculator), boil it. Rack your beer to the keg. Pour in sugar/water mix (it can still be hot), pressurize to a few psi to set the lid, and leave it for 2 weeks. At 2 weeks put it in the fridge and enjoy the next day.

You can get a little fancier too. I think it was Bilsch that suggested adding the sugar/water mix to the primary keg by unscrewing the PRV and pouring it in via a funnel. That would help reduce the amount of air introduced. Then wait an hour for fermentation to restart, then rack to the serving keg. You can also monitor the actual pressure in the keg and bleed off excess CO2 if you used too much sugar.

So if you were brewing a helles, would you let the keg sit warm for two weeks after a cold primary to get its carbonation? Does not seem like something you would normally do unless chasing LODO. Maybe adding lager yeast and keeping it cold?
 
So if you were brewing a helles, would you let the keg sit warm for two weeks after a cold primary to get its carbonation? Does not seem like something you would normally do unless chasing LODO. Maybe adding lager yeast and keeping it cold?

I'd hold it at the current fermentation temp. So for a helles you'd be in the 44-50F range by that point (assuming you ramp down as fermentation dwindles). For an ale i'd just leave it at whatever room temp was (60-75F).
 
Thanks. I might try adding a bit of sugar to scavenge but still augment with the canned CO2 to make up the difference to keep my set and forget pressures. Maybe the canned CO2 has some oxygen in it but it seems like a small amount. Leaving the keg in my wine fridge (fermenter) might be a problem as I often have another brew I want to get in there!

How long do you think it would take to scavenge any transfer induced oxygen just by adding a little sugar to the keg and keeping it at primary temps? If I am augmenting with canned CO2, maybe a few days?
 
Thanks. I might try adding a bit of sugar to scavenge but still augment with the canned CO2 to make up the difference to keep my set and forget pressures. Maybe the canned CO2 has some oxygen in it but it seems like a small amount. Leaving the keg in my wine fridge (fermenter) might be a problem as I often have another brew I want to get in there!

How long do you think it would take to scavenge any transfer induced oxygen just by adding a little sugar to the keg and keeping it at primary temps? If I am augmenting with canned CO2, maybe a few days?

I guess i'm confused why you are so dead set on adding bottled CO2. Add the sugar, pressurize the keg just enough to seal the lid, and let the yeast do the rest for you.
 
I serve from bottled CO2 at set pressures. Natural carbing was all over the place back when I used to bottle. I like consistency of set CO2 pressures. What I am hoping to achieve is lowered O2 in my keg environment (basically without changing my non-LODO practices). Getting some oxygen scavenging from a little fermentation sounds like a happy medium. I am wrong here?
 
I serve from bottled CO2 at set pressures. Natural carbing was all over the place back when I used to bottle. I like consistency of set CO2 pressures. What I am hoping to achieve is lowered O2 in my keg environment (basically without changing my non-LODO practices). Getting some oxygen scavenging from a little fermentation sounds like a happy medium. I am wrong here?

I understand your intent now.

I would still go after perfecting keg carbonation (which a well established science). But if you're still wanting to try a combined method, without even considering LoDO, I would suggest adding the priming sugar, sealing the lid up, and then just letting it sit. Don't connect external CO2 until it's time to serve. If you aim low it won't take much time to get to equilibrium. If you connect CO2 and add priming sugar you run the risk of over carbonation if the bottle CO2 is faster than the yeast.

It's really simple to monitor keg carbonation. You can get a keg disconnect, a fitting, and a pressure gauge, and leave it on the keg. Using the standard temperature/pressure/volumes co2 chart just bleed any excess pressure manually.
 
Natural carbing in the keg has been much more consistent for me than it ever was in a bottle. I think it's because the headspace is minimal compared to 50+ bottles, and the surface area of beer exposed to that CO2 in the keg is always the same.

I've always natural carbed Ales whenever possible, as I just like the taste better.

That said, I've had trouble carbonating and conditioning lagers in the keg at cold temps. My best, clearest and least sulfury tasting LODO lagers have all been cold fermented, kegged and warm carbonated, then cold lagered for several weeks or more.

You really need to be on top of your yeast handling, ferment time/temps etc. to nail the exact right day to rack an unfinished lager to a keg successfully, especially if you intend to let that lager finish at 40 or so...

But if you let it finish "primary" completely and keg it with spiesse or dextrose and carb up warm, then store cold, it's a snap and no off flavors from the tiny amount of warm fermenting.
 
Natural carbing in the keg has been much more consistent for me than it ever was in a bottle. I think it's because the headspace is minimal compared to 50+ bottles, and the surface area of beer exposed to that CO2 in the keg is always the same.

...

Actually, the headspace to beer ratio in a keg is about the same as in a bottle (about 6%.) I've measured both. So, a keg's worth of bottles will have about the same headspace volume as a full keg.

Surface area to volume ratio is much less important in natural carbonation than for forced carbonation. For forced carbonation, the rate of CO2 absorption by the beer is directly proportional to (headspace pressure minus the equilibrium pressure for the current level of carbonation in the beer) times the beer surface area. For natural carbonation, the CO2 is formed in solution, and the net CO2 flow is from the beer into the headspace, unlike for forced carbonation. The headspace pressure never exceeds the equilibrium pressure for the current level of beer carbonation. The only time surface area plays a role with natural carbonation is when the beer is chilled from carbonation temp to serving temp, when there is CO2 being reabsorbed into the beer from the headspace, but that is a small amount compared to the total amount of CO2 in the beer.

Brew on :mug:
 
Thanks for your replies. My next brew is a dunkleweizen so I will try some natural carbonation with a canned CO2 augment after a week or so.

if its a lager you probably want to wait a bit longer.... if the yeast are still working slowly you'll end up with overcarbonation. it might even be wise to just wait until you put it on tap. worst case its only going to be a little low, and after a few days on the serving gas it'll get topped up.
 
Actually, the headspace to beer ratio in a keg is about the same as in a bottle (about 6%.)

Surface area to volume ratio is much less important in natural carbonation than for forced carbonation.

I feel like we're on the same page here...

The headspace to beer ratio of 50 bottles might be the same, but in practice some have more headspace and some have less. And on a tapered neck bottle, that means more or less surface area of beer exposed to headspace, and more oxygen in some than others. Also, the priming sugar also varies - slightly, one hopes - so I stand by my point that natural carbing in a keg is much more consistent than in bottles.
 
if its a lager you probably want to wait a bit longer.... if the yeast are still working slowly you'll end up with overcarbonation. it might even be wise to just wait until you put it on tap. worst case its only going to be a little low, and after a few days on the serving gas it'll get topped up.

Thanks. I agree. There is a lot of time with a lager as my lager fridge is just my serving fridge...

BTW, I just noticed you are in Chesterfield. That is where I am from but I live in Texas. now I always wondered what the water is like to brew with as it is great tasting water to drink.
 
Couple of questions:

1.) I do all ales, and some strains are really fast. I just did a porter with WLP001-Cal Yeast on Wednesday and airlock activity is done. I have a temperature controlled chamber, so ramping up temps to speed up/clean up is possible. It started slowing down 3 days after pitching. This would mean me transferring to spunding vessel around 3 days. This seems quick but this is ok I assume?

2.) As far as checking gravity for when to spund, I see some people are doing a forced fermentation to gauge when to do this. I have a valve on the bottom on my ferm vessel (Speidel Ferm). Of course if I open it, the airlock sucks in air from up top. Are yeast still utilizing oxygen until FG is reached? I guess I'm asking is will the O2 introduced during a gravity check get used by the still active yeast, or is this too much additional oxygen.
 
Couple of questions:

1.) I do all ales, and some strains are really fast. I just did a porter with WLP001-Cal Yeast on Wednesday and airlock activity is done. I have a temperature controlled chamber, so ramping up temps to speed up/clean up is possible. It started slowing down 3 days after pitching. This would mean me transferring to spunding vessel around 3 days. This seems quick but this is ok I assume?

2.) As far as checking gravity for when to spund, I see some people are doing a forced fermentation to gauge when to do this. I have a valve on the bottom on my ferm vessel (Speidel Ferm). Of course if I open it, the airlock sucks in air from up top. Are yeast still utilizing oxygen until FG is reached? I guess I'm asking is will the O2 introduced during a gravity check get used by the still active yeast, or is this too much additional oxygen.


1. However long it takes to get you about 4-6 points away from FG

2. Pull your FFT after you initially aerate and pitch your yeast, get that sample warmer fast and you should see signs and be done before your normal batch. The time window is short though with ales.
 
BTW, I just noticed you are in Chesterfield. That is where I am from but I live in Texas. now I always wondered what the water is like to brew with as it is great tasting water to drink.

The tap water here in the St Louis area is overall pretty good. No foul odors and its only moderately hard and alkaline. I have made a few batches with it but i switched to RO water and haven't looked back.

I've also come to realize i prefer the taste of RO drinking water too (with tap water ice cubes), so i use my brewing RO system for drinking water at home too.
 
But this cannot be a hard and fast rule for all beer styles? Most if not all lagers taste better with a little sulfur flavor, or tank taste as Brandon puts it. However in a lot of ale styles those same sulfury notes are out of place. Take for instance an American brown that I make often. Transferring too early to the keg traps some sulfur that takes forever to age out if at all. Conversely if I allow an additional week in contact with the yeast cake these off flavors are cleaned up and/or vented as opposed to being trapped by the spund. My kolsch brewed with 2565 also benefits from longer primary time. Thus my use of the method to restart the ferment after that resident time but before transfer.
Am I losing staling protection from the yeast derived sulfites? Most probably.. but then Kölsch isn't a beer that stores well anyway.


Coming back to this thread again and read this and have a question based on the above concerns (which I had as well on the racking off the cake too early with sulfur components as well as a D-rest).

If you let the beer ferment completely out in primary (including D-Rest for lagers, the whole 9 yards), then rack the beer to a purged corny keg with about 3oz of priming sugar (boiled with the right amount of water), will this solve this issue of the beer not being fully ready to enter into the final stages of its journey and let the priming sugar scavenge the oxygen that got introduced while racking?

I am getting closer to getting a fully sealed process post boil-kettle to glass and if just adding the priming sugar with water in the serving keg to scavenge the last bit of oxygen from the racking process solves this, then I would rather let the beer finish out in primary completely before the x-fer and go the priming sugar route to maintain LODO procedures.
 
LOX = low oxygen

I thought LOX in this context is lipoxygenase is "a family of (non-heme), iron-containing enzymes most of which catalyze the dioxygenation of polyunsaturated fatty acids in lipids." The oxidized lipids result in "bad" flavors in your beer.

Around here folks talk about low dissolved oxygen or LoDO.

In other contexts LOX = Liquid OXygen or fillet of brined salmon (delicious with cream cheese on a bagel :D .)

Edit: Beat again by someone with faster fingers. :p

Brew on :mug:
 
Coming back to this thread again and read this and have a question based on the above concerns (which I had as well on the racking off the cake too early with sulfur components as well as a D-rest).

If you let the beer ferment completely out in primary (including D-Rest for lagers, the whole 9 yards), then rack the beer to a purged corny keg with about 3oz of priming sugar (boiled with the right amount of water), will this solve this issue of the beer not being fully ready to enter into the final stages of its journey and let the priming sugar scavenge the oxygen that got introduced while racking?

I am getting closer to getting a fully sealed process post boil-kettle to glass and if just adding the priming sugar with water in the serving keg to scavenge the last bit of oxygen from the racking process solves this, then I would rather let the beer finish out in primary completely before the x-fer and go the priming sugar route to maintain LODO procedures.

To be clear, moving your beer while active fermentation is going on will be the best way to protect your low oxygen flavors during transfer to the keg. What I posted was simply a hack to allow certain ale styles more resident time on the yeast cake and not violate the "transfer while active" idea. When it comes to lagers though, I totally agree with rabab25.. spunding with residual extract is king.
 
To be clear, moving your beer while active fermentation is going on will be the best way to protect your low oxygen flavors during transfer to the keg. What I posted was simply a hack to allow certain ale styles more resident time on the yeast cake and not violate the "transfer while active" idea. When it comes to lagers though, I totally agree with rabab25.. spunding with residual extract is king.

Sounds like if you are going to leave the beer on the cake to finish completely out before x-fer, racking to a keg with extract/dextrose to spur keg carbing quickly to scavenge the remaining oxygen is acceptable.

Again, I am moving towards a completely sealed system post boil so any racking I do will be from sealed fermenter to purged keg using C02 to push the beer around via out/in-posts to minimize oxygen exposure/light exposure so I am thinking the oxygen introduced in the racking process will be minimal to begin with and racking it to a purged keg with dextrose waiting in it to carb up the keg is a bonus.
 
Measure with a DO meter and you will be surprised.

I ferment in a corny keg and I run my gas out through the liquid out post of what will eventually be the lagering/serving keg, then put my PRV on the gas post of that keg to function as the airlock. The receiving keg gets purged with over 25x its volume worth of CO2 over the course of the ferment.

Before I started racking with extract, I would let the beer finish to FG in the fermenting keg then use a closed siphon between the two kegs to rack the finished beer. Once I got a DO meter I discovered that I was still picking up 0.4 ppm this way, which was enough to cause noticeable oxidation and flavor degradation of LoDO beer within a couple weeks. If you're not brewing LoDO beer to begin with, you may not notice the same level of sensitivity to post-ferment O2 exposure at such low levels.
 
Measure with a DO meter and you will be surprised.

I ferment in a corny keg and I run my gas out through the liquid out post of what will eventually be the lagering/serving keg, then put my PRV on the gas post of that keg to function as the airlock. The receiving keg gets purged with over 25x its volume worth of CO2 over the course of the ferment.

Before I started racking with extract, I would let the beer finish to FG in the fermenting keg then use a closed siphon between the two kegs to rack the finished beer. Once I got a DO meter I discovered that I was still picking up 0.4 ppm this way, which was enough to cause noticeable oxidation and flavor degradation of LoDO beer within a couple weeks. If you're not brewing LoDO beer to begin with, you may not notice the same level of sensitivity to post-ferment O2 exposure at such low levels.

This brings up a question: How do you measure the DO in a keg, without opening up the keg and letting in O2, which would affect the DO measurement? I know for commercially canned/bottled beer, they pierce the top/cap with a probe to take a sample (the can/bottle is then scrap), but that doesn't seem like a good way to deal with a keg.

Brew on :mug:
 
I pour some beer from a picnic tap as quickly/gently as I can into a glass and measure the DO as fast as I can. There is bound to be some O2 pickup this way, but as a point of comparison my measurements from spunded kegs are 0.0 ppm
 
Are folks still favoring the Extech DO600 meter? With a stated accuracy of 0.4 ppm and targets well under 1 ppm, I'm scratching my head trying to figure out why this meter is a meter of choice.

Thanks,
PlinyTheMiddleAged
 
Are folks still favoring the Extech DO600 meter? With a stated accuracy of 0.4 ppm and targets well under 1 ppm, I'm scratching my head trying to figure out why this meter is a meter of choice.

Thanks,
PlinyTheMiddleAged


The description on the website for this one states:

"The ExStik® II DO600 meter displays Oxygen level as percent of Saturation from 0 to 200. 0 percent or Concentration from 0 to 20.00 ppm (mg/L)."

Not sure where you saw 0.4ppm as their lowest available reading target..
http://www.extech.com/display/?id=14422

Was fixing to pull the trigger on one of these myself...
 
It's been posted on another forum:
These meters are not precise enough to reliably test DO to the accuracy needed for establishing the low concentrations of DO.

For this you need to spend $700 upwards (the optical ones many breweries use cost about $10,000). However it can tell you whether you have relative ingress of O2 (does my reading rise?) and it can tell whether one is in an acceptable ballpark.

Most importantly though: DO meters are irreplaceable when aerating wort.

For most of the primitive process control we need, they do fine and give a good price value ratio. They can also highlight gross errors in the process, just don't expect to detect 0.1 mgl reliably. That could show up as 0.1 or 0.5.

If you read the manual carefully you will see a section where they mention that leaving the electrode immersed for too long, the electrode itself will remove oxygen.

followed up by

Yes, you can assume unidirectional movement (of oxygen) at our levels. That's why on a relative scale, they (Extech DO meters) are helpful in diagnosing the weak points in your system, despite not being the most precise.
 
Measure with a DO meter and you will be surprised.

I ferment in a corny keg and I run my gas out through the liquid out post of what will eventually be the lagering/serving keg, then put my PRV on the gas post of that keg to function as the airlock. The receiving keg gets purged with over 25x its volume worth of CO2 over the course of the ferment.

Before I started racking with extract, I would let the beer finish to FG in the fermenting keg then use a closed siphon between the two kegs to rack the finished beer. Once I got a DO meter I discovered that I was still picking up 0.4 ppm this way, which was enough to cause noticeable oxidation and flavor degradation of LoDO beer within a couple weeks. If you're not brewing LoDO beer to begin with, you may not notice the same level of sensitivity to post-ferment O2 exposure at such low levels.

to me, this pushes some logic buttons, because you're oxygenating way above 0.4 ppm to ferment. if you rack onto a fermentable, there is fermentation happening to scrub the O2 just as when you oxygenate wort in the first place
 
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