Reducing oxygen from dry hopping- add hops early or suspend above beer?

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@scrap iron
Good to know thanks, I'm going to use my sous vide with hard drive magnet on the outside. The picture above was from my first go and was just using some magnets I had at home. It was tenuous the hold on the hop bag but the hard drive magnet on the outside with those magnets vac sealed for the inside was good.
I did stitch a little pocket inside the bag to hold the magnet in position, this meant the hops went in and then I could position it so the magnet was in the middle this reduced the dangle of the bag by half with the magnet on the far side of the bag so it drooped down either side of the magnet.
 
I tried the magnet drop method with my Anvil ss fermenter, but my hops expanded so much with the humid environment that they clogged the bag I was dumping from. I have since gotten a Flex+ and doing dumps from a 1.5 TC port.
 
I'm going the commando approach for dry in hopping the batch I'm brewing this weekend. On my last batch I pulled out a condensed muslin sack of hops, there's no way good utilization is happening. I will rely on cold crash and a filter when I transfer.
 
I don't know what type hops others are using that are having troubles. I suspect pellet hops, but I only use whole leaf hops for dry hopping. And I use two smaller nylon hop bags to get less crowding and better utilization. I save pellets for Boil Kettle.
 
This is my method & I use a fermzilla


I ferment without any pressure initially, and purge a liquid filled (saniclean) receiving keg (cut gas diptubes so I can release all sanitizer) with the co2 from fermentation. I wait until after a few hours of active fermentation before I hook up the receiving keg to ensure air has been purged from the fermzilla prior to the keg purge.

I then dry hop some time shortly after after high krausen, but with at least 25% attenuation yet to be achieved. Basically as soon as fermentation starts to slow a bit.

I hook up my tank at 2 psi (this ensures positive pressure when I open the gas post for dry hop) to the liquid post (remember to always purge all gas lines line of air prior to connecting to any gas posts during all points of the process) . Then I unscrew the gas post & quickly add 5g of ascorbic acid along with the dry hops (via a homemade funnel built from a pet bottle). Then I screw the gas post back on & hit the lid with 25 psi, purge once and hit the lid again with 25 psi. Spunding valve is then set to 25 psi for remaining fermentation. After dry hop I also remove temperature control to encourage the yeast to free rise and quickly complete fermentation while scavenging oxygen. If my gravity reading is too low at dry hop time and I may have missed the window, then I add 10g of dextrose along with the ascorbic acid.

After adding the dry hops I wait a few hours to allow oxygen to be scavenged, then I shake the **** out of the fermenter to kick the hops back into suspension. I do this a few morn times over the next 12 hours then I allow the yeast to settle out. After 24 hours total I do a closed transfer to the keg & set spunding valve on keg at 30 psi to allow fermentation to finish in the keg. My floating dip tube in the fermzilla is a flotit with dfi screen to ensure hops aren't sucked up at transfer. My receiving keg has a clear beer draught system dip tube without a screen to ensure no clogging during transfer.

The final serving vessel has now had just about all oxygen scavenged prior to the eventual cold crash after target gravity is reached. It is also free of particlate hop matter & mostly carbonated with pure fermentation sourced CO2 as opposed to bottled CO2 (which is only 99.95% pure)

I prefer free balling the hops vs adding a baggy

I also use epdm rubber o rings on my kegs which are much less O2 permeable than silicon.

I also only hook up gas & liquid lines for serving. When not serving they are disconnected. All of my lines are eva barrier that are very resistant to O2 permeation

If tje keg is undercabonated I may leave the gas attached for a few days at desired psi level to allow carbonation to finish & then disconnect gas once achieved
 
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Wow, I haven't been on this site for a few years “listening” to you peeps. The concern over oxidation has definitely increased.
I’ve always been really careful to avoid oxidation, but not to the extent described herein.
 
Wow, I haven't been on this site for a few years “listening” to you peeps. The concern over oxidation has definitely increased.
I’ve always been really careful to avoid oxidation, but not to the extent described herein.
Don't stumble onto the Low Dissolved oxygen thread, you might never brew again for fear of oxygen.
Oxygen more of a problem for some beer styles than others.
 
I brew many styles, but most of my competition success has been with SUPER HOPPY IIPA. As mentioned, very careful, but not to the extent mentioned in this thread.
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Wow, I haven't been on this site for a few years “listening” to you peeps. The concern over oxidation has definitely increased.
I’ve always been really careful to avoid oxidation, but not to the extent described herein.
Not to go off down the low oxygen rabbit hole, but yeah there are many opinions.

Some disagree but it really seems to me like all the obsession with minimizing oxygen coincides just about exactly with the rise of NEIPA. And that is one of the styles most affected by O2.

I’ve been brewing 25 years and oxygen was discussed in years gone by and associated with cardboard and stale flavors. But we were all brewing with plastic buckets and carboys, nobody was co2 purging every container, and nobody was building specialized oxygen free transfer systems til just a couple years ago. Yet amazingly, we made decent beer that we enjoyed.
 
Yet amazingly, we made decent beer that we enjoyed.

Yeah, but - I'm 100% positive my doing things like purging kegs has helped tremendously and my younger self would have been really glad to know about some of my older self's current practices. I enjoyed my beer then but I am positive it's better today.
 
Oxidation almost made me give up on brewing as all of my IPAs tasted like cardboard.

My beers were exposed to air at two points.
Dry hopping
Kegging

At the time, I had no mindset to purge air from my fermenter so oxidation began at dry hop, by the time the beer was transferred to keg and carbd, it was garbage.

Keeping my beer from oxygen has completely improved my beer and kept me home brewing. I am working on better fermentation temp control now, hoping to get another bump in beer quality.
 
moved to a unitank conical so dont have this issue anymore, but what i would say just as an FYI in regards to the "stipping aromas" question is that only about 5% of the hop pellet is surface area, so if it were to be oxidized while waiting to get dropped, it would be pretty minimal with respect to the total size/mass of each pellet
 
Oxidation almost made me give up on brewing as all of my IPAs tasted like cardboard.

My beers were exposed to air at two points.
Dry hopping
Kegging

At the time, I had no mindset to purge air from my fermenter so oxidation began at dry hop, by the time the beer was transferred to keg and carbd, it was garbage.

Keeping my beer from oxygen has completely improved my beer and kept me home brewing. I am working on better fermentation temp control now, hoping to get another bump in beer quality.
Hate to be that guy, but I dry hop in my Ss brewtech brew bucket without purging and auto siphon into my kegs, and I've never had a beer taste like cardboard. I make sure not to disturb the beer and add a little ascorbic acid to the keg before racking, but I've been good to go.

I'm not saying oxidation isn't a thing, but I think technique has a lot to do with the final product. I obviously purge the keg after packaging.
beer1.jpg
 
Hate to be that guy, but I dry hop in my Ss brewtech brew bucket without purging and auto siphon into my kegs, and I've never had a beer taste like cardboard. I make sure not to disturb the beer and add a little ascorbic acid to the keg before racking, but I've been good to go.
I am curious how much the ascorbic acid helps.

My IPAs used to be crappy, which looking back was likely most caused by oxidation. The biggest step I took was to stop using a secondary which I am sure was 95% of my oxidation issues. I also cringe at how often I would open up my fermenter to take a gravity sample or my fairly lazy method of transferring to a keg, but I am sure the secondary transfer was the biggest issue.

Before I first brewed an NEIPA I did research and made changes to support cold crashing without suck back (using a mylar balloon) and a fully closed keg transfer. I do still quickly remove the stopper on my fermenter to add dry hops, but other than that I keep my beers sealed off from the outside air. I moved to doing closed keg transfers for all my beers, figuring that an extra $0.25 worth of CO2 and a extra 15 minutes is worth it, even if I don't notice oxidation issues in styles like a Porter.

I have also been playing around with purging my kegs with CO2 from fermentation. This has worked well. It means I use less CO2 than I would otherwise and I have a sanitized and purged keg ready to use!
 
I am curious how much the ascorbic acid helps.

My IPAs used to be crappy, which looking back was likely most caused by oxidation. The biggest step I took was to stop using a secondary which I am sure was 95% of my oxidation issues. I also cringe at how often I would open up my fermenter to take a gravity sample or my fairly lazy method of transferring to a keg, but I am sure the secondary transfer was the biggest issue.

Before I first brewed an NEIPA I did research and made changes to support cold crashing without suck back (using a mylar balloon) and a fully closed keg transfer. I do still quickly remove the stopper on my fermenter to add dry hops, but other than that I keep my beers sealed off from the outside air. I moved to doing closed keg transfers for all my beers, figuring that an extra $0.25 worth of CO2 and a extra 15 minutes is worth it, even if I don't notice oxidation issues in styles like a Porter.

I have also been playing around with purging my kegs with CO2 from fermentation. This has worked well. It means I use less CO2 than I would otherwise and I have a sanitized and purged keg ready to use!
All very good steps to prevent oxygen. I use a cold crash guardian to prevent O2 and suck back, and I think it's worked great.

I would like to say the ascorbic acid is making a difference. I've used it in every keg since I bought it back in the Summer, and I feel my beers pop more. They seem brighter to me, if that makes any sense. It's 1 teaspoon per keg, and for the cost, I'm going to continue to use it. I think I got a pound for like $24.

I know my transfer process isn't ideal, but I just wanted to chime in that we can make very good beer without overthinking too much. Especially for a potential new brewer being turned off to the idea of such a complicated process. Would my neipas benefit from closed transfer? I would like to say yes, without a doubt. Is it worth the extra hassle for me? Not right now. Maybe if they sat in the keg for months and months, but I drink or share it all usually within 2 months. Right now, I'm not noticing any drop in aroma or flavor. Might get into closed transfers in the future, but right now, I enjoy my process, and it's relatively hassle free.
 
This is a varied hobby, so one size does not fit all. But I prefer the discuss the best possible methods so people know the pinnacle approach instead of only hearing about the convenient approach which then becomes standard practice. This is very common in the homebrew world. This imho applies to new brewers even more as why not learn the gold standard instead of other ways which lead to other outcomes.

I recently set up a keg purging approach to my cold side. This entailed drilling a hole in my wine fridge and running an EVA Barrier tube out of the fridge. That tube is connected to my keg for that batch which is then connected to a spunding valve. The keg gets purged during fermentation and pressurized when the beer is spunded. All of this is controlled by turning the spunding valve! Could not get any easier and I am kicking myself for not knowing about/doing this many years ago. Both the fermenter and keg are at the same pressure so pressure transfers are just hooking up a closed loop and letting gravity take care of the rest.

If a new brewer was told about this or shown, it would be their standard practice going forward. It is easy, uses free, natural CO2 and keeps O2 away from your product. The O2 thing can be dismissed but it is the focus of the professional brewing world. No way around it, the beers are better if O2 is kept away from them.
 
This is a varied hobby, so one size does not fit all. But I prefer the discuss the best possible methods so people know the pinnacle approach instead of only hearing about the convenient approach which then becomes standard practice. This is very common in the homebrew world. This imho applies to new brewers even more as why not learn the gold standard instead of other ways which lead to other outcomes.

I recently set up a keg purging approach to my cold side. This entailed drilling a hole in my wine fridge and running an EVA Barrier tube out of the fridge. That tube is connected to my keg for that batch which is then connected to a spunding valve. The keg gets purged during fermentation and pressurized when the beer is spunded. All of this is controlled by turning the spunding valve! Could not get any easier and I am kicking myself for not knowing about/doing this many years ago. Both the fermenter and keg are at the same pressure so pressure transfers are just hooking up a closed loop and letting gravity take care of the rest.

If a new brewer was told about this or shown, it would be their standard practice going forward. It is easy, uses free, natural CO2 and keeps O2 away from your product. The O2 thing can be dismissed but it is the focus of the professional brewing world. No way around it, the beers are better if O2 is kept away from them.
I do always mention closed transferring as the end game when talking transfers, especially hazies. I understand your post 100% and would agree 100%. Reducing/eliminating oxygen uptake is one of the first things we are taught when making beer. I was just offering anecdotal evidence as to what has worked for me, in the event that someone doesn't have a closed transfer system and is experiencing oxidation. YMMV.
 
No worries. I can say I was 100% not taught about oxygen exposure when I started the hobby 20 years ago or until about 4 years ago when I started learning about LODO brewing. I was still open transferring into my kegs from the fermenter when I started the journey in 2018. Oxygen exposure is difficult, so it gets a lot of bad press but it is absolutely the path to making better beer. Even if it is only the on the cold side.
 
This is a good discussion. Reducing cold side oxygen has been a major driver for my brewing changes in recent years. Remarks like @wepeeler 's about two months of hop splendor without ideal transfer make me wonder: what other factors beside oxygen have folks found to help preserve hop aroma and flavor?
 
This is a good discussion. Reducing cold side oxygen has been a major driver for my brewing changes in recent years. Remarks like @wepeeler 's about two months of hop splendor without ideal transfer make me wonder: what other factors beside oxygen have folks found to help preserve hop aroma and flavor?
I have to say I think ascorbic acid makes a difference. Again, anecdotal evidence on my part, but the beer shows and speaks for itself.
 
All very good steps to prevent oxygen. I use a cold crash guardian to prevent O2 and suck back, and I think it's worked great.

I would like to say the ascorbic acid is making a difference. I've used it in every keg since I bought it back in the Summer, and I feel my beers pop more. They seem brighter to me, if that makes any sense. It's 1 teaspoon per keg, and for the cost, I'm going to continue to use it. I think I got a pound for like $24.

I know my transfer process isn't ideal, but I just wanted to chime in that we can make very good beer without overthinking too much. Especially for a potential new brewer being turned off to the idea of such a complicated process. Would my neipas benefit from closed transfer? I would like to say yes, without a doubt. Is it worth the extra hassle for me? Not right now. Maybe if they sat in the keg for months and months, but I drink or share it all usually within 2 months. Right now, I'm not noticing any drop in aroma or flavor. Might get into closed transfers in the future, but right now, I enjoy my process, and it's relatively hassle free.

Headspace in a keg or bottle is a bigger killer than pickup during a transfer.

I would definitely avoid a bottling bucket, but could see success racking directly from primary to keg via autosiphon and filling the keg to the brim.

An advantage of a liquid purged keg is that the headspace will have very little O2. Whereas if you only purge the headspace there will still be w significant amount of O2 remaining.

Bottling is terrible for a hoppy beer unless you can purge headspace or cap on foam. Bottling in 22s is better than 12s because headspace is less

One other idea I'm planning on toying with is to use SMB in my sanitizer when kegging. This way residual sanitizer won't have any DO. The remaining SMB will be inconsequential.
 
Headspace in a keg or bottle is a bigger killer than pickup during a transfer.

I would definitely avoid a bottling bucket, but could see success racking directly from primary to keg via autosiphon and filling the keg to the brim.

An advantage of a liquid purged keg is that the headspace will have very little O2. Whereas if you only purge the headspace there will still be w significant amount of O2 remaining.

Bottling is terrible for a hoppy beer unless you can purge headspace or cap on foam. Bottling in 22s is better than 12s because headspace is less

One other idea I'm planning on toying with is to use SMB in my sanitizer when kegging. This way residual sanitizer won't have any DO. The remaining SMB will be inconsequential.
I purge the keg headspace. I set to 30 psi and purge at least 10x. Not claiming it's ideal, but it works for what I'm doing. Never had a cardboard beer yet.
 
I have to say I think ascorbic acid makes a difference. Again, anecdotal evidence on my part, but the beer shows and speaks for itself.
any reason why to not use vitamin c tablets, crushed with a mortar and pestle, instead of finding a source of powdered ascorbic acid?

thanks
 
I purge the keg headspace. I set to 30 psi and purge at least 10x. Not claiming it's ideal, but it works for what I'm doing. Never had a cardboard beer yet.
If you're doing it 10x that should mostly do it. Especially if you've got ascorbic acid in there.

Btw, oxidation on a hoppy beer won't be cardboard. Cardboard is more of a lager off flavor. Hoppy oxidized ales taste more like a bad jam or jelly where the flavor tastes muddled.

If you aren't practicing any other LODO methods on the hot side to preserve fresh grain flavor it doesn't matter too much. A hazy IPA isn't too much about malt character anyway. If you were doing a hoppy pilsner dor example it might matter more.
 
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any reason why to not use vitamin c tablets, crushed with a mortar and pestle, instead of finding a source of powdered ascorbic acid?

thanks
Vitamin C can have other flavor additives in it to make it taste like citrus. You don't want that in your beer.

Powdered ascorbic acid is relatively cheap. You can get 2 pounds of it for $20 which is more than you will need in your lifetime.

Add 5g when you dry hop or keg and call it a day.
 
You doing pressure the whole time or only after dry hopping and initial fermentation complete? What yeast strains?
I have only done three pressure batches. One was a west coast IPA with 1 oz Centennial & Cascade dry hop using Imperial 007 yeast. I had pressure from the start with bottle CO2 at 2 bar. I used the magnet method to drop the hops. Wanted to do it after fermentation but I think they expanded and slid out of my holder early. But the whole system was closed. The hop aroma from the transfer first runoff was amazing. And to speak to how damaging O2 is and how challenging it is to keep the really good stuff, those unique aromas did not make it to the serving stage. It does not take much to kill these flavors and aromas. Once you get a closed system going to see how much impact even just the bottled CO2 has with its very small percentage of oxygen included. Once you put the beer on gas for serving it starts going downhill.

The frustrating thing is that you get to taste the magic before it fades!
 
I have only done three pressure batches. One was a west coast IPA with 1 oz Centennial & Cascade dry hop using Imperial 007 yeast. I had pressure from the start with bottle CO2 at 2 bar. I used the magnet method to drop the hops. Wanted to do it after fermentation but I think they expanded and slid out of my holder early. But the whole system was closed. The hop aroma from the transfer first runoff was amazing. And to speak to how damaging O2 is and how challenging it is to keep the really good stuff, those unique aromas did not make it to the serving stage. It does not take much to kill these flavors and aromas. Once you get a closed system going to see how much impact even just the bottled CO2 has with its very small percentage of oxygen included. Once you put the beer on gas for serving it starts going downhill.

The frustrating thing is that you get to taste the magic before it fades!
I think another reason aroma drops out is from yeast floculating and pulling the hop aroma down with it.

I recently purchases a fermzilla with a hop bong. I'm going to experiment with soft crashes and dump all the yeast before dry hopping going forward. I think dry hopping on bright beer might even help more than oxidation loss. I want to go with natural carbonation too, so the hop bong would theoretically let me dry hop the beer after its been carbonated.

I've noticed of my beers dry hopped in primary the hop aroma tends to stick around more with non flocculent yeast, but when the yeast drops so does the aroma.

Getting the beer off the yeast cake I'm sure would also probably help, but tough to do if you don't have a conical type fermentor or dry hop in the keg.

I've found dry hopping in the keg brings wonderful (and lasting) aroma, but with some varieties of hops it can get vegetal if left for extended periods on the hops. Some vareities its absolutely fine though. This is why I want to dry hop in the fermzilla, but off the yeast/
 
any reason why to not use vitamin c tablets, crushed with a mortar and pestle, instead of finding a source of powdered ascorbic acid?

thanks
I want make sure it's food grade. OTC Vit C, like @Unicorn_Platypus said, can contain flavoring.
If you're doing it 10x that should mostly do it. Especially if you've got ascorbic acid in there.

Btw, oxidation on a hoppy beer won't be cardboard. Cardboard is more of a lager off flavor. Hoppy oxidized ales taste more like a bad jam or jelly where the flavor tastes muddled.

If you aren't practicing any other LODO methods on the hot side to preserve fresh grain flavor it doesn't matter too much. A hazy IPA isn't too much about malt character anyway. If you were doing a hoppy pilsner dor example it might matter more.
Never gotten any jam like flavors in my hoppy beers either. Kolsch is my house beer, and I've gone 3 months without any sign of cardboard. Bright to the last drop. Of course, 3 months is extremely rare as most of my beer doesn't even see the end of month 2. The only off flavor I've struggled with for really light beers is DMS. 90 min boil fixes that 99% of the time.
 
The plan was to let the beer finish, drop the hops, let sit for 3-5 days, cold crash then transfer to the keg. All went well outside of the hops maybe dropping a bit early. What I tasted was the runoff out of the cold crashed fermenter. I run the first bit to a 2-liter bottle via a KegLand "T" to capture any sediment the dip tube might suck up first and to push all of the O2 out of the transfer line. Clear beer gets put into the keg and everything gets left behind in the fermenter. The aroma in the kegged beer was very nice but some orange citrus that was pretty strong was gone. (never expected or got these hop flavors from Centennial or Cascades). Still learning but this is night and day better than anything I had ever done before. The combination of pressure fermentation and closed transfer created a "commercial" flavor. Kind of like - "that is why their IPAs taste this way...".
 
The plan was to let the beer finish, drop the hops, let sit for 3-5 days, cold crash then transfer to the keg. All went well outside of the hops maybe dropping a bit early. What I tasted was the runoff out of the cold crashed fermenter. I run the first bit to a 2-liter bottle via a KegLand "T" to capture any sediment the dip tube might suck up first and to push all of the O2 out of the transfer line. Clear beer gets put into the keg and everything gets left behind in the fermenter. The aroma in the kegged beer was very nice but some orange citrus that was pretty strong was gone. (never expected or got these hop flavors from Centennial or Cascades). Still learning but this is night and day better than anything I had ever done before. The combination of pressure fermentation and closed transfer created a "commercial" flavor. Kind of like - "that is why their IPAs taste this way...".
Even though the beer was cold crashed there could still be some yeast in suspension that later flocs out in the keg

Btw, the other thing I would recommend is disconnecting both has and liquid lines between servings.

Also getting epdm rubber for the keg On rings as opposed to silicon helps prevent permiability
 
Unhooking the lines is a bridge too far for me. Not only because it is very difficult to reach the connection in the fridge, I think it is over the top. But no doubt it helps. Moving to EVA Barrier tubing helps with this. I changed all of my keg seals to buna-N, so that area should be covered. :)

I recommend this to all folks - change out all the rubber seals as the standard rubber lets oxygen pass through. Seems small but remember it is 24 hours a day, every day the beer is on tap or lagering.
 
Unhooking the lines is a bridge too far for me. Not only because it is very difficult to reach the connection in the fridge, I think it is over the top. But no doubt it helps. Moving to EVA Barrier tubing helps with this. I changed all of my keg seals to buna-N, so that area should be covered. :)

I recommend this to all folks - change out all the rubber seals as the standard rubber lets oxygen pass through. Seems small but remember it is 24 hours a day, every day the beer is on tap or lagering.
I don't drink very often and got too lazy to hookup lines. I just use a picnic tap 2.0 and pull beer whenever I want some
 
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