dry hop methods & oxidation

[Dr. Dirk]

I originally posted this in terrym's thread "Newbies Guide to Dry Hopping Your Beer", but I suppose it's a bit too in depth for that, so the thread got closed just as the discussion started getting interesting. I'm starting a new thread because I'm very interested in other folks' experiences:

I LOVE hop aroma and flavour, so I love dry hopping! I end up using 170g per 19L in my American-style IPA: Chinook, Willamette, Nelson Sauvin, Cascade, Amarillo, and Citra. I tried a number of different methods, but ended up preferring nylon bags weighed down with SS spoons (bag/spoons boiled first to sanitize). I much prefer the taste of whole hops to pellets. The pellets end up being more astringent and less flavourful/aromatic than whole.

People say the problem with bags is that the hops aren't exposed to the beer as much as when they are put in freely. I've tried throwing them in loose, but like other posters, I've found they just float on top, develop a weird crust, and are a PITA when bottling (I keg these days, don't bottle anymore; more on that later). Loose hops also soak up alot of the brew! Weighing the bags down with spoons at least ensures that the hops are submerged. I put just enough spoons in to weigh the bag down, but not enough to sink it and have it sit on the trub, mainly because I don't want to have to reach way down into the brew to get it. Also, when it's time to get the hops out, I can use my hands (sprayed with Starsan) to squeeze my precious brew out of the hops. After a while of doing this, it dawned on me that the spent hops still retained ALOT of their aroma, so I started actually pressing and squeezing the hop bags while they were still submerged in the brew. I now do this for a few minutes before I remove the bags, ensuring the beer is flowing over and through them, getting all that flavour and aroma (and giving them that good final squeeze after they're out to get my beer out of them!)

In order to dry hop this way, you obviously can't be using carboys, as you can't fit the bag in through the neck (or wouldn't be able to get it out!) I used to use plastic buckets, but made the leap to the Brewtech SS fermenters a while ago, and do really like them now that the pain of the expense has faded.

One more interesting anecdote (this is where the kegging comes in): when I made the switch from bottling to kegging, I wasn't ready to try force carbing on the very first batch I put into a keg, so I just batch primed it like I had been doing previously with bottles. All good. On the second batch I tried force carbonating for the first time, and there was a dip in quality of the finished beer. One of my more discerning friends went from singing the praises of my brew to not being able to drink it at all! This prompted a rash of research on my part, scrolling through the forums to see what could be the matter, and a number of blind taste tests among a few friends. We tasted bottled, batch-primed kegged, and force-carbed kegged, and 100% of us could tell the difference and preferred the batch-primed kegged, then the bottled, and not so much the force-carbed kegged, which kind of had an almost lager taste creeping in, which was completely off-putting to that one discerning friend. To me it wasn't undrinkable, but was definitely inferior. I'm not 100% sure, but from my research and my own taste tests, I suspect oxygen; all the squeezing of the hops bags had been introducing oxygen into the beer, of which I was blissfully unaware while I was still bottling and on my first kegged batch because the yeast had been consuming the oxygen along with the priming sugar and saving my batches. When I tried force carbing, that didn't happen, and the oxygen affected the quality and taste of the final beer. At least that's my theory.

These days, I'm happily squeezing all the hoppy goodness out of my bags (both dry hop bags AND brew addition bags: I squeeze them around with a large SS spoon after I put them in, and wring them out with my hands after the wort cools) and batch priming my kegs, and I have to say, my IPA has by far the most hoppy flavour and aroma of any I've tried. A negative side effect is that it's ruined me on most other beers; I don't even bother ordering beer when I'm out, knowing that I'll just be disappointed.

I've been wanting to post my experience here for a long time, but haven't because I knew it was going to be a massive post and take a long time, but here it finally is. I'm interested to hear what other folks think.

Cheers, and thanks for reading if you've made it this far!

 

[Dr. Dirk]

Some of the interesting replies I'd gotten before the thread got closed:

terrym: Noting that I am usually one of the first on here to downplay infection risks as part of normal homebrewing practices, and in spite of the wonders of Starsan and its sanitising capability, I don't think I would want to immerse my arm and hand into an FV full of beer to squeeze a hop bag, since I think it's asking for trouble.

I've just brewed batch #120, and have been hand-squeezing hop bags since about batch #15 (about 3 years now) and have never had a bad batch (knocks on wood!). I will often use a spray bottle full of Starsan solution to sanitise surfaces, and keep a bucket of StarSan solution around to refill the spray bottle (it lasts for months). Come bag squeezing time, I dunk my hands in the bucket and use my hands to ensure my forearms are all wet, give it 30 seconds, and have at it. Come to think of it, I remember one time forgetting to put the starsan on my hands before squeezing the bags and still ended up not spoiling the batch. By the dry hopping stage, the beer is already alcoholic, so somewhat resistant to microbes. And I imagine the hopped up beer getting squeezed through my fingers probably killed whatever might have been on them, as hops are also anti-microbial. I would still definitely recommend Starsan on your hands and forearms though! (even more important if you're squeezing the last bits of hoppy goodness out of your boil additions, as the wort is much more susceptible to infection)

pottsworth: I'm slightly dubious of the ability of yeast to save beer from the effects of oxidation.
The lag phase in primary is normally a few hours, so presumably in bottles it will also take a few hours for the yeast to scavenge all of the oxygen? Is this not long enough for the oxygen to already have had its effects?

As I understand it, the major effect of oxidation is degradation of flavour over time, so if the yeast scavenge the oxygen as they consume the priming sugar, perhaps it's effects are mitigated?

foxy: Bottle or keg yeast once in anaerobic mode does not scavenge oxygen when there are sugars available, they do take up any small amount of DO but that's all.

If this is true, then my theory is incorrect, and I'm still in the dark as to why the force-carbed version of my IPA is noticeably inferior to the keg-conditioned or bottled versions. I've had the occasional wonky bottle if it wasn't filled all the way, but the beer coming out of the keg (keg-conditioned version) is always bright (colour) and wonderfully hoppy. I spent a bunch of time reading different forums on this, and opinion definitely seems to be divided. Just read through a thread on Homebrewtalk where someone posted "The fact that yeast do scavenge oxygen is so well known that MBAA includes it in their bottling guidelines." I'm not a member of MBAA so can't read their guidelines, but it's posts like those that inspired my theory. Here's a link to the discussion if anyone is interested: https://www.homebrewtalk.com/forum/threads/yeast-and-oxygen.642044/

 

[ghocking]

Shame this didn't get more responses... very interesting. Especially regarding the hop bag squeezing, I'd have thought that would introduce too much oxygen.

 

[soupdragon]

I'm more interested in priming in the keg. It's something I've never even considered since I've had my kegs. If it's a free boost to a better beer then I'm all in. Must admit that when I still made 22.5 litres and bottled a few from the surplus after I'd kegged, the bottled was always the better beer. Might do some reading and give it a go. Might take ages to clear down though

Cheers Tom

 

[Buffers brewery]

I'm trying to "perfect" my dry hopping method . I tend to dry hop mostly NEIPAs, so huge quantity of dry hops. So I use pellets rather than whole hops so don't need to be squeezed out. If I'm dry hopping my beer, it doesn't see the atmosphere (air) after it goes into the fermentation bucket until it is poured into a glass. I carbonate by priming sugar solution and serve from a plastic pressure barrel. I tried pressure carbonating once. Nah! Quick, yes, taste, nah IMO.

 

[Stu]

I'm trying to "perfect" my dry hopping method . I tend to dry hop mostly NEIPAs, so huge quantity of dry hops. So I use pellets rather than whole hops so don't need to be squeezed out. If I'm dry hopping my beer, it doesn't see the atmosphere (air) after it goes into the fermentation bucket until it is poured into a glass. I carbonate by priming sugar solution and serve from a plastic pressure barrel. I tried pressure carbonating once. Nah! Quick, yes, taste, nah IMO.

I find that pellets tend to retain a lot of liquid.

 

[Buffers brewery]

My opinion is that dry hopping will result in additional losses due to absorption. Pellets seem to settle with the yeast during cold crashing, although, to be honest I haven't used whole hops for dry hopping. My instincts tell me that the losses would be greater with whole hops versus pellets after a cold crash no squeeze method, but that's my instincts not fact

 

[ghocking]

I'm more interested in priming in the keg. It's something I've never even considered since I've had my kegs. If it's a free boost to a better beer then I'm all in. Must admit that when I still made 22.5 litres and bottled a few from the surplus after I'd kegged, the bottled was always the better beer. Might do some reading and give it a go. Might take ages to clear down though

Cheers Tom

You're right and I might try that next time too.

I have 19l corny kegs, how would you make up your priming solution for those?

My opinion is that dry hopping will result in additional losses due to absorption. Pellets seem to settle with the yeast during cold crashing, although, to be honest I haven't used whole hops for dry hopping. My instincts tell me that the losses would be greater with whole hops versus pellets after a cold crash no squeeze method, but that's my instincts not fact

I read the OP very shortly after I'd disposed of a fermentation bucket that I'd kegged from the day before. My initial sample of the beer was a bit underwhelming hop wise yet the aroma from the bucket was amazing. Can help but think I've left so much behind. I was using pellets.

 

[soupdragon]

You're right and I might try that next time too.

I have 19l corny kegs, how would you make up your priming solution for those?

I'd more than likely just put some sugar in the keg and syphon on top of that. Just treat it as a large stainless steel bottle so of thing.

Cheers Tom

 

[Jim Brewster]

I'm a big believer in throwing the pellets into the fermentation vessel and letting them settle out over a week or so, it's always worked for me for ales and IPAs.

The pellets initially float and then break up to a powder/paste on the top, getting as much extraction as possible. Then as they trigger a second bout of yeast activity they get combined into the rolling lava lamp currents in the fermenter. In my mind this yeast activity will inhibit any oxidation issues. Once this phase is done they settle on the top again but most begins to sink. Once they have settled out the beer is ready to bottle or can be 'cold crashed' if it's being particularly stubborn and not clearing

I've not done a really soupy NEIPA though, I suspect it wouldn't work very well

 

[Buffers brewery]

I've not done a really soupy NEIPA though, I suspect it wouldn't work very well

Au contraire Rodney . I brew NEIPA regularly and drop 250g of hop pellets into the brew half way through fermentation. Always cold crash all my brews for 3-4 days before transfer to a PB. Works fine for me.

 

[ghocking]

What steps do you take to keep the hop matter from getting into your PB?

And do you use anything to avoid the addition oxygen through cold crashing? I've seen talk of using a balloon?

 

[Buffers brewery]

What steps do you take to keep the hop matter from getting into your PB?

And do you use anything to avoid the addition oxygen through cold crashing? I've seen talk of using a balloon?

Hi @ghocking . I've modified my fermentation bucket to have a magnetic floating dip tube. During fermentation, dry hopping and cold crash the float and the end of the dip tube are held above the brew keeping them clear of any crud/trub. To transfer the finished beer to my PB the float is released and drops into the beer, taking beer from the top. When the float assembly settles on the hop/yeast debris the dip tube end is about 5mm above it therefore doesn't suck much, if any, debris.
Yes, I use a balloon during cold crash. I usually connect a balloon a day or two after krausen and leave it connected until the finished beer has been transferred. N.B. bubbler remains connected all the time.

 

[ghocking]

...to have a magnetic floating dip tube.

Something along these lines? I'd never thought of that but sounds perfect!

 

[Buffers brewery]

Yes, only I made my own version using polycarbonate sheet and a float ping-pong ball...

You can see it clinging to the side of the bucket. PTFE coated magnet on the inside and a standard magnet on the outside.

 

[Buffers brewery]

I'm in the process of making a new fermentation vessel which is proper air tight, has a large opening, includes my design of trapdoor dry hoppers and magnetic dip tube. Keeps me busy