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

[tracer bullet]

Valid point. Maybe with letting out a decent force of CO2 from a floating dip tube, you will have an exerting force coming out of the fermenter, reducing the amount of o2 that can make its way in.

You can certainly flush the area with some CO2 and get the O2 out rather quickly. The water analogy - you have a bucket of dirty water, and add some clean water into it. The dirty water mix flows over the edges. After a while you end up with a bucket full of clean water, or of course very close enough to it.

That's not exactly how it works but is probably closer as a way to think of it.

 

[RyPA]

The way I was thinking of it is suppose you have a garden hose with CO2 coming out of it, with a slight force. It would be difficult/impossible for any other gas to get in.

Similar thought process for having a decent CO2 load in the fermenter, it would come out of the top like smoke coming out of a chimney.

 

[Beermeister32]

To weigh down a hop bag, I have some glass marbles I use. You can easily suspend a bag with a loop of unflavored dental floss. Pull the floss and the bag drops in. Old school…

 

[josephort]

To weigh down a hop bag

Do people generally recommend weighing a hop bag? I was just planning to drop mine into the fermenter and let them float- do you get more flavor if it sinks?

 

[Beermeister32]

I don't know if any one has tested that - probably somebody has. I always submerged mine.... !

 

[RyPA]

@josephort I'd say yes you want them fully submerged. This will improve the contact area of the hops/beer. If they are not weighted down, the bag will float, and the top of the hop sack will not be contacting beer.

I am considering throwing hops in commando for my next NEIPA, just trying to figure out the logistics to avoid o2 exposure

 

[josephort]

As promised, here's a photo of the setup I used:



The sour cream container was necessary to keep the hop bag from dangling into the top of the beer. I cut a bunch of big holes in the bottom and weighted it down so it would sink quickly. Even with this little innovation, the whole thing was hanging closer to the krausen than I planned, and the hops at the bottom may have gotten slightly damp. This was partly because I wasn't able to keep the thread as tight as I wanted, so it's dangline a few inches below the top of the fermenter, and partly because I had slightly less trub loss than I expected so the beer line was a bit higher up than normal. I think having more headspace would've made this a lot easier- if I do this again I'll brew a slightly smaller batch.

I set this up as the krausen was falling and let it sit for several days, then lowered it yesterday. No problems there, the hop bag went straight into the beer.

I'll report back when I start drinking the beer. Overall though I'd say this is a totally viable strategy for anyone who wants to do late dry hops but is concerned about O2. Whether it's really necessary or actually improves the beer quality, IDK.

I do think using magnets could be less finicky than doing the string thing, but it would require pretty strong magnets and some way to seal them off from the beer, neither of which I have on hand. (rare earth magnets can corrode and leach toxins, apparently). If this beer turns out especially good, maybe I'll look into that for the next one.

 

[Beermeister32]

Innovative!

 

[DuncB]

@scrap iron

I have used the magnets vac sealed and in a hop bag very successfully. They held very well with hard drive magnets ( rare earth ) on the outside, I have just got some sous vide magnets and plan to use these next time instead of the vac sealed magnets. Starsan for the bags and sousvide magnets for me.
If you didn't think that starsan would do the job you should be able to at least pasteurise in 80 C water or boil them as they are for sous vide cooking.

The great benefit I find as well as the closed aspect is you can drag the hops below the beer / wort level and also swish them about to stir up the wort and ensure it all mixes well, then remove them when you think they are done and let them drip into the beer.

@josephort I do pressure ferment my NEIPA after a few days, there's no way to hold the aroma in the beer when so much CO2 is produced I think about 400 litres for a 20 litre batch if memory serves me.

Not a picture of an NEIPA by the way.

 

[scrap iron]

@DuncB
I just brewed my APA Tuesday and used the sous vide magnets. Just put one inside the bag and soaked in a bucket with star-san. I tested them with another one on the outside and it seemed to hold well with my SS bucket. I'll see how they do with the hard drive magnets next time. I might try two sous vide next time in the hop bag and see if holds it out of the beer better. cheers.

 

[DuncB]

@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.

 

[doogie]

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.

 

[RyPA]

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.

 

[scrap iron]

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.

 

[Unicorn_Platypus]

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

 

[brick_haus]

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.

 

[DuncB]

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.

 

[brick_haus]

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.

 

[DuncB]

Agreed there is only so far that I go to avoid oxygen, it's become my norm now so it seems less of a faff.

 

[bwible]

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.

 

[BrewnWKopperKat]

Wow, I haven't been on this site for a few years “listening” to you peeps. The concern over oxidation has definitely increased.

There is a tendency in some forums to (over) amplify whatever the current signal is.

I’ve always been really careful to avoid oxidation

Yup. Numerous ways to avoid or minimize.

amazingly, we made decent beer that we enjoy.

Yup.

 

[tracer bullet]

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.

 

[RyPA]

I almost gave up on brewing until I began doing O2-free practices. My IPA's always ended up getting darker and tasting like crap and I was ready to give up. It's amazing how a few extra steps in your brew day/fermentation/transfer can make the beer that much better.

 

[mac_1103]

Oxidation takes time. I have been advised to just drink my beers faster. Makes sense, but maybe that's because I'm drunk?

 

[Beermeister32]

Oxidation takes time. I have been advised to just drink my beers faster. Makes sense, but maybe that's because I'm drunk?

You don't sound drunk to me. Maybe a bit oxidized....

 

[RyPA]

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.

 

[SanPancho]

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

 

[wepeeler]

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.

 

[CascadesBrewer]

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!

 

[wepeeler]

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.