When to dry-hop while pressure fermenting

[nonamekevin]

Brewed morebeers hop blonde yesterday, all grain for the first time. I think it went okay. My question was on the timing of dry hop additions while pressure fermenting. Recipe states to dry hop in secondary fermentation, 3-5 days. I'm keg fermenting and don't plan on doing a secondary fermentation. Right now I've been fermenting into a blow-off tube for about a day now, and was going to switch to pressure fermenting after another day or two.

Looking for suggestions on when you would throw the spunding valve on, what pressure, and when you would dry hop.

 

[beerfactory]

All things equal, I would spund after 4 full days fermentation. Then spund while gradually ramping temp to the higher end of your yeast's preferred zone. Release pressure 3 days prior to packaging and dry hop. At that point my process is a closed transfer to serving keg... so I am little help from there.

If you are serving unitank/same keg you have fermented, I don't have any experience with dry hopping while serving. I assume it would be fine with the beer chilled, that you consume at a reasonable rate and have a floating dip tube w/ filter (or something worked out to prevent poppet clogs).

 

[nonamekevin]

Thanks beer factory. To clarify my original post, I was thinking of close transferring to the serving keg, which I didn't consider as a "secondary fermentation".

Using your process, I would:

-ferment 4 days w/ blow-off
-spund after 4 days
-3 to 5 days before transferring to serving keg, release pressure and dry hop
- after dry hopping for 3-5 days, closed transfer to serving keg.

That's more of a plan than I had. If anyone has anything to add, or other ideas, I'm open to it.

 

[T Murph]

@nonamekevin I have dry hopped in the serving keg a number of times with good success. I put leaf hops in a bag with weights to hold it down. Put them in a sanitary keg then purge the keg with Co2 and do a closed system transfer into the keg. Put it in your cooler for few days then enjoy.

 

[Elric]

Thanks beer factory. To clarify my original post, I was thinking of close transferring to the serving keg, which I didn't consider as a "secondary fermentation".

Using your process, I would:

-ferment 4 days w/ blow-off
-spund after 4 days
-3 to 5 days before transferring to serving keg, release pressure and dry hop
- after dry hopping for 3-5 days, closed transfer to serving keg.

That's more of a plan than I had. If anyone has anything to add, or other ideas, I'm open to it.

If you are only going to start pressure after 4 days, I would just elect to not bother until after adding the dry hop. Adding hops after the beer has started to take on pressure risks causing a giant foam over (due to nucleation off of the hop matter) and you will be losing all of the pressure you have built up in the fermenter as well as causing a bunch of gas to come out of suspension in the beer as well. It's a necessary evil if you are truly pressure fermenting, but since you are more spunding than fermenting, I just see it as more of a complication than anything that will be helpful for you. Drop in your hops and then use gas to pop the fermenter up to the psi you want ahead of kegging it.

 

[beerfactory]

pressure risks

that's true. the main idea is to dry hop under some had pressure, right? so the suggestion to puff some C02 in post dry hop is sound (even if you have been spunding for a week - which I also agree is likely unnecessary).

I have not found fermentation temperature and pressures involved to have driven all that much C02 into solution. That's using a blow off for the active fermentation and spunding for a week prior to dry hopping. Maybe some people have had a foaming issue - that is definitely a mess I would not want to clean up.
Could be a case of "because you can, doesn't mean you should"

 

[monkeydan]

I'm about to return brewing after several years and have been researching this issue extensively! I think issues with previous brews may have been related to oxidation so wanted to start using pressure fermentation and subsequent closed transfers using corny kegs.

These are two of the main options regarding dry hopping I've seen...

1. Suspend your dry hops in the primary fermenter with a hop sack and magnets. After ~2 days, drop the hops into the beer for however long you plan to dry hop and then transfer to serving keg.

2. Add dry hops to serving keg, purge with CO2 (you can use the CO2 from fermentation to purge the serving keg by attaching the spunding valve to the gas in post on your keg), then closed transfer onto the dry hops and leave them until the keg is kicked.

Regarding when to start spunding, opinions seems to vary.

Some people set the valve to required pressure (generally 10-12 PSI) straight away, then allow the fermentation to build up that amount of pressure.

Others use a blowoff tube for the first 2-3 days then switch to the spunding valve.

Not sure what the difference is

Just want to reiterate I have no personal experience, but would be interested to know what you decide and what you would change in future!

 

[micraftbeer]

I've done several brews under pressure. Here are my findings and how I process currently:

1. I've found very slight taste difference for beers fermented under pressure when I've done split batch when fermenting with lager yeast. My takeaway on this is if I have the ability to ferment lagers cold, I do. But if I can't, I can still get a decent beer out of it (fermenting at 10-14 psi after first 24 hours with just venting.

2. Fermenting under pressure slows down fermentation rate. So unless you want your process to take longer, you have to raise temperature to try to offset the slowdown effect of pressure. For this reason, on my ales, I just hook up blow-off tube for most of the ferment.

3. For my ales where I do add spunding, I just add it at the end, when it's a couple points within predicted FG. And I set it up to just be at ~1-2 psi, just to make sure I have a good "CO2 headspace" before dry hop.

4. I have different fermentors with different dry hop addition options, but my process is typically the same. Once I've hit FG and am flat on my Tilt reading for 2-3 days, I add the dry hops, close the spunding, and turn up the heat by about 5 degrees. This temperature increase is for my diacetyl rest, but it also helps create positive pressure in the fermentor again to keep oxygen from wanting to sneak in. I then sit like that for about 2 days, then cold crash.

5. When cold crashing, it depends on my fermentor. My FermZilla All Rounders fit inside by beer fridge, so I just put the whole fermentor in there and cold crash for 3 days before transferring to a serving keg, all under pressure. If I'm using a conical that doesn't fit in fridge, I do a closed transfer to my specific cold crash keg that has a floating dip tube. Cold crash in that keg for 3 days, and then closed transfer into serving keg.

6. My experiments with IPA fermenting under pressure to try to retain more hop presence didn't produce any difference. So the only reason I mess with "pressure ferment" is the 1-2 psi at the end of fermentation like I mention above, for purposes of minimizing oxygen intake risk.

 

[micraftbeer]

I realized my reply spent more time talking about pressure fermentation than dry hopping itself. Here are the different ways I dry hop, based on which fermentation vessel I'm using:

1. X1 Uni+ Conical with Collection Bottle on the bottom. When ready to dry hop, I close the bottom dump valve, remove the collection bottle (messy) and dump the collected fermentation debris, sanitize, then fill it with my dry hops. I re-attach to the fermentor, but before opening the dump valve (to send dry hops up into the beer), I pressurize the collection ball with bottled CO2 via pressurization cap and vent 4x. I leave the collection ball pressurized, then I open the dump valve and hops get jettisoned into the beer.

2. X1 Unit+ Conical with Brewers Hardware Dry Hopper on top. I fill the Dry Hopper with hops, with the ball valve closed that leads through the lid into the fermentor. Same pressurize with CO2 and purge 4x, leave it pressurized, then dump the hops into the beer.

After the above two methods, since I have a cooling rod in there, after 1-2 days of dry hops sitting in there, I start circulating cooling water to get the beer to ~50F. This happens pretty quickly and helps consolidate the hop solids at the bottom. When I do pressurized closed transfer out, it is via a floating dip tube, so it pulls off the bottom. The brief 50F chill helps get me pretty good transfers into my cold crash keg without much debris.

3. FermZilla All Rounder with Pressure Kit. The fermentor is around 1-2 psi at end of fermenation due to Spunding. I vent that (it's low enough pressure to not cause an internal eruption), remove the lid, and drop in the dry hops. I then do the pressurized fill with CO2 & purge head space. I recall reading Blichmann website about study where air/CO2 MIX QUICKLY when you open fermentor, but Oxygen ABSORBS SLOWLY. So with this brief lid opening exposure, my approach is to purge the mixed headspace right away as best I can. On this setup, whole fermentor goes into cold crash fridge so I don't have to do any cooling water effort to get hops to drop before transfer.

4. FermZilla All Rounder with Pressure Kit x2. I have 3 of these fermentors (for split batch experiments). I have done this method once (currently finishing dry hopping). ~2 Days after beer starts fermenting, I connect the Gas fitting on the fermenting beer to the liquid fitting on an empty sanitized FermZilla. I put the dry hops in the empty FermZilla and close the lid and set Spunding to 1-2 psi. The CO2 produced from the fermenting beer gets pushed through the liquid dip tube on the dry hop Fermzilla, and then bubbles out through the gas port. Once fermentation is done, closed transfer from one to the other via the liquid posts. Since the transfer is done via floating dip tube, the yeast cake is left behind in the first fermentor and I have just beer, dry hops, and CO2 in the other. I then can shake and agitate this up without fear of intermixing oxygen, and agitation supposedly leads to faster dry hop absorption in the beer. After 1-2 days, I will put in cold crash fridge to get hop debris collected at bottom, and 3 days later transfer into serving keg.