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

[Bassman2003]

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.

 

[wepeeler]

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.

 

[Bassman2003]

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.

 

[sibelman]

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?

 

[Bassman2003]

Kind of a side topic but I have started using pressure fermentation (1-2 bar) and the hop character is off the charts compared to non-pressure batches.

 

[BongoYodeler]

Kind of a side topic but I have started using pressure fermentation (1-2 bar) and the hop character is off the charts compared to non-pressure batches.

I have a Blow Tie ordered, just waiting for it to be delivered. I need to learn more about this.

 

[wepeeler]

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.

 

[Unicorn_Platypus]

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.

 

[Unicorn_Platypus]

Kind of a side topic but I have started using pressure fermentation (1-2 bar) and the hop character is off the charts compared to non-pressure batches.

You doing pressure the whole time or only after dry hopping and initial fermentation complete? What yeast strains?

 

[wepeeler]

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.

 

[faithie999]

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

 

[Unicorn_Platypus]

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.

 

[Unicorn_Platypus]

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.

 

[Bassman2003]

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!

 

[Unicorn_Platypus]

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/

 

[wepeeler]

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.

 

[Bassman2003]

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...".

 

[Unicorn_Platypus]

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

 

[Bassman2003]

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.

 

[Unicorn_Platypus]

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

 

[Bassman2003]

I agree, the 'no line' tap is a good way to go. Straight out the keg. Get a flow control QD and you are set if you don't mind opening the door each time to get a beer.