How to avoid beer contacting oxygen during dry hopping (carboy)?

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Miles_1111

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I am using carboy as fermentor. Is there any better way to avoid the wort from contacting air during dry hopping? Thank you.
 

VikeMan

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I am using carboy as fermentor. Is there any better way to avoid the wort from contacting air during dry hopping? Thank you.
With a carboy, to more or less completely avoid picking up new O2 from the air, the only way I can think of would be to do a closed transfer of the finished beer to a purged, dry hop containing keg, and then another closed transfer to a purged serving keg.

Otherwise, you could flood the carboy's open headspace (quasi-purge) with CO2, before and again after gently and quickly adding your hops.
 

FswBG

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There are carboy caps that allow for a pickup tube and ball lock gas insert to allow pressurization. However, the glass can only handle a few psi and could cause real injury.

I use a carboy as backup in case my main FV is in use and go with @VikeMan 's described method to flush the carboy headspace with CO2 using a beer gun, slowly lower hops in, and then flush again.
 

eric19312

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Do the dryhop while fermentation is still active. This technique works for all sorts of IPAs not just NEIPAs. You can wait till it is slowing down or just put them in there at high krausen. If worried you might lose some of the impact just bump up the dry hop amount a bit. What you lose to off gassing and yeast stripping may well be made up by increased mixing due to fermentation activity.
 

Panderson1

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Honestly this did wonders (below). Dry hop (no bag) while fermentation is still active then connect this. Cold crash later on. The only time the hops should have touched oxygen is when you poured them in. Then try and do a clean transfer to the keg and purge like crazy. You could try and purge some oxygen out of the siphon i guess


 

Birrofilo

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A user in this forum described a nice system: he hangs the hops on the upper "dry" wall of the fermenter and keeps it in place with a magnet (i.e. with two magnes, one inside the fermenter and the other outside).
The fermenter is full of CO2 during fermentation.
When he wants to dry hop, he takes away the magnet on the outer part of the fermenter. This causes the bag to fall inside the beer, without opening the lid. This is, I believe, compatible with a CO2 blowoff system.

A variation of this technique could be suspending the hop bag above the wort, through a string which gets out of the fermenter through the bubbler. You keep the hop bag suspended until the day in which you want to dry hop. You could also "fish back" the hop bag when needed. This doesn't need a metal fermenter. I don't think this could be coupled with a CO2 blowoff system.
 
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Miles_1111

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Do the dryhop while fermentation is still active. This technique works for all sorts of IPAs not just NEIPAs. You can wait till it is slowing down or just put them in there at high krausen. If worried you might lose some of the impact just bump up the dry hop amount a bit. What you lose to off gassing and yeast stripping may well be made up by increased mixing due to fermentation activity.
This is probably the easiest way to do it. Dryhop on 3rd or 4th day after adding yeast when it is at high krausen. Will give it a shot.
 

Dgallo

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Do the dryhop while fermentation is still active. This technique works for all sorts of IPAs not just NEIPAs. You can wait till it is slowing down or just put them in there at high krausen. If worried you might lose some of the impact just bump up the dry hop amount a bit. What you lose to off gassing and yeast stripping may well be made up by increased mixing due to fermentation activity.
Tht will help with o2 but it causes another entire issue...hopburn. During fermentation yeast bind polyphenols and protiens, causing them to stay in suspension longer. So yes you’ve minimized 02 pick up but now you’ve created an astringent beer that will need a month of conditioning time to be enjoyable. And if you weren’t good with your transfer and picked up o2, when it’s finally time to drink, it’s also oxidized.
@Miles_1111 if you’re looking for an affordable set up to minimize o2 pickup and close transfer, here is my thread on how to convert a fermonster to a closed fermenter with pressure/closed transfer capabilities.
 

BongoYodeler

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A user in this forum described a nice system: he hangs the hops on the upper "dry" wall of the fermenter and keeps it in place with a magnet (i.e. with two magnes, one inside the fermenter and the other outside).
The fermenter is full of CO2 during fermentation.
When he wants to dry hop, he takes away the magnet on the outer part of the fermenter. This causes the bag to fall inside the beer, without opening the lid. This is, I believe, compatible with a CO2 blowoff system.
May have been me as this is what I do. And I also have a large ss nut inside the hop bag for weight, and rather than removing the outer magnets I just slide them down the fermenter submerging the hops in the beer, suspended above the trub.
 

tracer bullet

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I use stoppers with dual holes, one for a thermowell and the other for a blow-off tube. When I dry hop, I remove the thermowell and replace it with a small barb fitting (barb one side, flare the other) that I attach to my CO2 supply. Then I remove the stopper and add the dry hops. Lastly the stopper goes back in place and I purge for a while with a low flow of CO2. After about 30 seconds or so I disconnect the CO2 and put the thermowell back in.

The purging isn't perfect but I feel it's decent (and closed, it comes out the blow-off). Same for removing the barb and putting the thermowell back. SOme O2 will get in but I can do it pretty quickly. It isn't perfect but I'm pretty sure it's better than nothing and I'm positive my hoppy beers are hoppier for longer than they used to be.
 

Birrofilo

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Another issue which is usually noted regarding dry hopping during fermentation is that fermentation causes CO2 to fly away bringing with it the volatile aromatic compounds.

We should never forget that essential "oils" in plants are not really "heavy oils". If you put some essential oil (which you can buy at a herbalist's) in your hand palms and you rub your palms against each other, a great aroma will be released and your palms will end up clean! (Try doing that with olive oil...).

Essential "Oils" are actually quite volatile and you should not think of them as oils. If you put them in your fermenter during CO2 production you will lose most of them in the air just as when you put them in the kettle.
 
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Panderson1

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^ I remember reading about the same IPA batch split into 4 separate fermenters and dry hopped pre, during and after fermentation. I forgot the results lol but it was interesting
 

CascadesBrewer

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^ I remember reading about the same IPA batch split into 4 separate fermenters and dry hopped pre, during and after fermentation. I forgot the results lol but it was interesting
Ohhhh...you got me curious. I am pretty convinced myself that you get the best hop flavors with minimal contact time.

I am using carboy as fermentor. Is there any better way to avoid the wort from contacting air during dry hopping? Thank you.
I am a strong advocate of avoiding cold side oxidation. I would definitely advocate not transferring to a secondary, or doing something like taking off the entire lid of a bucket to dry hop, but I do think sometimes we take things too far.

What I do (which should be similar to the OPs situation) is 1) measure out my dry hops into a plastic cup, 2) lift up the #10 stopper on the top of my Fermonster, 3) dump the dry hops in and 4) put the stopper back in place. Maybe there is some oxygen that is in the hops, maybe pouring the hops in pulls some oxygen into the fermenter, maybe the 30 seconds while the stopper is off some oxygen got in. I just don't see it as enough for me to worry about. I have tried blasting some CO2 into the headspace before putting the stopper in place. I am just not convinced it is needed.

That is the only time I will open my fermenter for a hoppy beer. I use a mylar balloon setup to avoid suck back during cold crashing and I close transfer into a purged keg.
 

DuncB

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I use the hops in a bag with two magnets and it works well. If you want to double dry hop have two bags. Do test that your magnet and bag stays out of the wort and krausen, otherwise it soaks up liquid and drops in earlier than you want.

I now don't release the magnet just slide it down the side of the fermenting vessel. This means I can sort of move it around a bit every day to spread the goodness. Not necessary if you do it during active ferment as the wort is fairly lively.

Have found that the computer hard drive magnets are super strong and cheap from salvage yards. To allow sterilising and avoid magnet deterioration I have vacuum sealed them. Ideally I suppose a plastic food safe dip would be best but not sure of a source for this.
IMG_20201108_170431.jpgIMG_20201108_170441.jpg

Also means I can move the hops out of the ferment to drain out before transfer to the keg. This reduces vessel loss.
 
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BongoYodeler

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I use the hops in a bag with two magnets and it works well. If you want to double dry hop have two bags. Do test that your magnet and bag stays out of the wort and krausen, otherwise it soaks up liquid and drops in earlier than you want.
I use 4 rare Earth magnets, two inside two outside, and position the bag horizontally near the top of the fermenter. I learned. My first attempt I used weaker magnets which failed and the resulting beer was named Splash Down ipa. ;)
 

DuncB

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I think the hard drive magnets are rare earth. My pictures above were before I got the hard drive magnets. I had a splash down as well when the krausen came up, so far too early and I had to fish the hop bag out ( wasn't in too long ) . Reloaded and reset two bags instead of one with fresh hop pellets. I have refrozen the splash down hops and await a further journey for them.
 

BongoYodeler

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I’d be very careful to seal rare earth magnets before immersing them in beer. Neodymium is in the “probably not too toxic but we don’t really know” category, and who knows how much could leach out of the magnets.
Yep. I vacuum seal mine...well just the ones that go inside the fermenter anyway.
 

DuncB

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I just use the " normal magnet " vacuum sealed inside the vessel and the rare earth magnet " naked " on the outside.

I suspect the force from rare earth to rare earth could damage the fermentasaurus wall or make the hop bag very difficult to move.
 

DarrellQ

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I use the hops in a bag with two magnets and it works well. If you want to double dry hop have two bags. Do test that your magnet and bag stays out of the wort and krausen, otherwise it soaks up liquid and drops in earlier than you want.

I now don't release the magnet just slide it down the side of the fermenting vessel. This means I can sort of move it around a bit every day to spread the goodness. Not necessary if you do it during active ferment as the wort is fairly lively.

Have found that the computer hard drive magnets are super strong and cheap from salvage yards. To allow sterilising and avoid magnet deterioration I have vacuum sealed them. Ideally I suppose a plastic food safe dip would be best but not sure of a source for this.
View attachment 721777View attachment 721779

Also means I can move the hops out of the ferment to drain out before transfer to the keg. This reduces vessel loss.
I had no idea someone on here had already tried this. I'm glad to hear it was successful. I plan to try it next time I dry hop. My plan was put a large washer in a small zip bag and put it inside the small muslin bag containing the hops. I plan to use one of these magnets on the outside of the carboy. I tested it and it works great. https://www.amazon.com/gp/product/B07QX3HTKD/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1
 

BongoYodeler

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I had no idea someone on here had already tried this. I'm glad to hear it was successful. I plan to try it next time I dry hop. My plan was put a large washer in a small zip bag and put it inside the small muslin bag containing the hops. I plan to use one of these magnets on the outside of the carboy. I tested it and it works great. https://www.amazon.com/gp/product/B07QX3HTKD/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1
Those are the magnet I use. They're incredibly strong. **Warning - don't get them too close to your head, they'll pull random memories out of your brain!!
 

DuncB

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Regarding the metal or magnet you put inside the muslin ( or other material ) means the bag dangles off this point.
I secured the metal/ magnet into the side of the muslin bag filled with hops and then this can be positoned so hops and the other half of the bag is trapped. It dangles less far this way which means the fermenter can have less headspace.
 

BongoYodeler

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Reckon I could use those magnets to hold the drip tray onto the kegerator quite neatly?
I've seen that very thing, either somewhere on this site or on a YouTube video. I believe the person used epoxy to attach the magnets to the drip tray and that held it to the fridge. It looked like it held so strongly that he couldn't pull it off. He had to slide it off at the edge of the door. Sliding like that might cause scratches I would think. Not sure though.
 

moreb33rplz

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Buy a $40 corny keg to ferment, then either drop a hop bag in and pressurize/purge a few times, or put dry hops in a second keg, purge it, and closed transfer to it.
 

DuncB

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Why not drill / use the other hole in a carboy lid put a CO2 line in that and let CO2 in slowly, then you can force the hop pellet in against the flow of CO2 exiting. If you get bored and you have the flow balanced the hop pellet will hover in mid air like an executive toy!
 

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Why not drill / use the other hole in a carboy lid put a CO2 line in that and let CO2 in slowly, then you can force the hop pellet in against the flow of CO2 exiting. If you get bored and you have the flow balanced the hop pellet will hover in mid air like an executive toy!
I would recommend eye protection for pressurized applications.
 

cfjcarl

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I had no idea someone on here had already tried this. I'm glad to hear it was successful. I plan to try it next time I dry hop. My plan was put a large washer in a small zip bag and put it inside the small muslin bag containing the hops. I plan to use one of these magnets on the outside of the carboy. I tested it and it works great. https://www.amazon.com/gp/product/B07QX3HTKD/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=
[Edit: Moved reply outside quoted text -Mod]
So if you have the hoppes in the fermenter while its feementing and lets say your able to keep it from getting wet. What prevents it from releasing all the aromatics out the air lock?
 
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DarrellQ

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Good question. Maybe pressure? I haven't tried that process yet, but I will say, I just did a recipe that I have done many times without dry hopping, and this time, I dry hopped for the last 3 days before kegging. I opened the carboy while pumping in some Co2, and I tossed in 2 oz of Cascade hops. I can honestly say that I don't see any hops flavor or aromatic difference between this brew and what I haven't dry hopped in the past. So, I'm not a big fan of dry hopping at this point.
 

IslandLizard

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I opened the carboy while pumping in some Co2, and I tossed in 2 oz of Cascade hops.
That's a decent process actually! The carboy neck is narrow, streaming CO2 into the headspace through a piece of tubing while adding the dry hops counterstream.
Although gases mix freely, there is less chance oxygen moves in while CO2 is moving out, especially during the 1-3 minutes or so it takes.

I use a similar procedure with my bucket fermenters, and drilled an "accessory port," a 1" hole in the lid for adding dry hops or other things while streaming CO2 in through the airlock hole. I can even purge that headspace a few times afterward, as my bucket lids seem to seal pretty gas tight, they bulge under pressure.
 

cfjcarl

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I tried pumping CO2 into my clonical fermenter as i poured in the dry hops. Time will telll.
 
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