This really isn’t going anywhere since fermentation appears to have finished after about 36 hours from pitching, so roughly 24 hours of actual fermentation.
Rather than let it sit on the spent yeast for another 4 days I closed the butterfly valve, gently de-pressurised, and chucked in the remaining hops before fitting the floating dip-tube and re-pressurising to 15 PSI ready for chilling in 4 days time. Normally we see some fermentation re-start with the hops, and as the vessel is already pressurised I’m hoping that any CO2 produced will help remove any oxygen that was introduced by my carefree approach to dry-hopping from the top.
Fermentation appears to have slowed to nothing and most of the Krausen has cleared, so I’d like to throw the finishing hops in now and have the last remnants of fermentation clean up the introduced O2. In an unexpected development I seem to have lost pressure from the FV, with the gauge on the spunding valve indicating 0 PSI at one point. Tightening up both top disconnects resulted in the needle budging a little, but she really seems to be done now. Hopefully we’ll get another burst now that the hops are in and that will act as insurance against suck-in during cold-crashing.
Fermentation seems to have well and truly stopped since about 3 days ago, so yesterday I blipped the temperature by 2℃ to finish things off before switching off the heater altogether, and today I dry-hopped 25g Citra as per recipe.
It’s weird to be seeing the fermentation curve flattening out 8 points shy of FG, especially for a light beer such as this. Are we really only on for 3.8% ABV here? The upward trend (it did peak at 4.0% ABV) is also weird, and I can only assume that what we’re seeing is a combination of Tilt’s aversion to absolute readings and maybe some yeast climbing aboard near the end of the ride.
Another possible explanation is that Voss didn’t like the near-death experience when I accidentally froze the contents of my beer fridge a couple of weeks ago. Luckily my sachets of kveik were surrounded by the cold-packs it shipped in, which I’m hoping acted as thermal buffers. Certainly no untoward signs where fermentation is concerned up to now.
Let’s let the Citra stew for 2 days, then start to ramp down towards cold-crashing on Friday night. Bottling date tentatively set for Tuesday 7 Feb.
The fermentation curve has levelled out and there are just a few bubbles in the dip-tube every couple of seconds, so now feels like a good time to get my finishing hops in while there’s still a smidge of activity to guard against oxygenation.
With that I added a great big bag of assorted hops as per recipe, also fitting the newly arrived filter to the floating dip-tube. Hopefully when it comes to transfer we’ll get a little more across than last time before the disconnects clog up with green goop.
When I dry-hopped this brew 2 days ago I neglected to fit the floating dip-tube, and since we still have 2 days left to run (and the merest suggestion of continued fermentation) I thought I’d tease the lid off, fit the dip-tube, and re-pressurise using canned CO2, hopefully purging any introduced oxygen and increasing the spunding valve to 10 PSI in the process. I also gave the Fermzilla a gentle swirl, because the thick blanket of hops hadn’t moved since I added them. They’re now very well dispersed and it all looks great – will start cold-crashing tomorrow. I wasn’t originally going to do this, but there’s so much hop matter in here now that I really want to drop out as much as I can before sending it to the keg, even if I lose some of that legendary cloudiness.
The Fermzilla’s been sitting at 5 PSI since primary started about 5 days ago, so I just teased off the top and chucked in 80g of Chinook, 50g Nelson Sauvin, and 40g Citra as per the recipe. No purging or faffing. There was a small island of foam at the centre of the brew, indicating that some slight fermentation was still going on despite the Tilt graph having been flat for 2 days now. That bodes well; I wanted a tiny bit of activity in order to dispel any introduced oxygen, so hopefully we’ll get minimal DO and still great hop utilisation.
I’m not due to dry-hop this one for another 4 days but fermentation appears to be well and truly over now, so lets get those hops in there and get the brew off that dead yeast 4 days sooner. I used a new method to do this today, more details here.
Fermentation seems to have all but finished now, so I added the 20g bag of anonymous hop pellets which came with the kit. The top of the brew looks clear, and there’s only slight signs of Krausen having touched the inside of the lid – can’t have been exactly fierce then. Hopefully adding the hops will kick-start things again so that there’s no too much oxidation.
The fermentation curve has flattened out so I’m dry-hopping this 2 days early with the hope that I may still get a little bit of CO2 produced and minimise oxidisation induced by just chucking in the hops via top hatch, quick and dirty.
Before opening the FV I slowly de-pressurised to 5 PSI via the PRV and then started unscrewing the top hatch until it continued to empty itself that way, which saves wrestling with the otherwise stuck lid.
Having dumped the hops, partially closed the bottom valve to prevent them sinking into the jar, and fitted the sanitised floating dip tube, I re-fastened the top hatch and refitted the spunding valve and pressure gauge, but did not add any CO2. I’m keen to see how much is produced over the next two days (dry-hopping sometimes seems to kick-start things again) but will add gas manually if nothing happens in order to counteract shrinkage during cold-crashing in 2 days time.
One Hour Later
And we’re back to 10 PSI. Amazing. I’m reducing gently to 5 PSI via the PRV in order to let out what is hopefully just oxygen from the top of the FV, confident it’ll re-fill itself soon enough.
Threw in 25g Citra and 25g Centennial pellets just now via the main opening, also added the floating dip tube. Fermentation has been slowing over the past couple of days and the curve is now pretty much level, though there were still some pops coming from the blow-off bottle. The top of the brew has been clear of Krausen for a couple of days too, and I’ve never seen so much activity with the top clear, then again I don’t often connect the blow-off bottle so it may be perfectly normal and not something related to this first go with Hornindal.
On gently de-pressurising via the PRV there was a great rush of foam and now I had Krausen again, almost level with the opening. Threw the hops in pretty quickly and refitted the lid, knowing that the small amount of fermentation that’s still going on will help drive out any air induced by the procedure but also take away some of the hop aroma. That latter point isn’t as pertinent as it would normally be, given that I’m kegging this one day before a 2 week break aboard and therefore expect to lose some hops over that time anyhow.
As soon as the lid was back on and the blow-off tube connected I saw more bubbles in the sanitiser, and the spunding valve gauge started to creep up again. Using the PRV to re-pressurise gives less control than reducing the spunding valve, but at least I know that the valve is set to where it needs to be. Will I use this method next time? Not sure. The whole point behind reducing pressure gradually is to minimise structural stress on the vessel and the floating digital hydrometer, so will keep an eye on both of those now that I’ve tried another way.
My 3 day hop additions went in today since the fermentation curve has now flattened out. I used the usual method of gradually de-pressurising the FV, almost-closing the butterfly valve, and then chucking the pellets in via the hole in the top. Before refitting the lid I attached the sanitised floating dip tube.
Although the top of the brew was clear at the start of this procedure, by the time the FV was open there was a good amount of foam on top, maybe half an inch, which I’m putting down to carbonation releasing on depressurisation. It also had an unusual aroma, but that’s likely down to the 30℃ fermentation temperature. New territory here. Anyway, pressure started building up again as soon as the lid was back on, though it seems to be stopping at 5 PSI. That’s cutting it pretty fine for cold-crashing so I’ll add some gas from my bottle later today if it doesn’t increase on its own.
I’ve been enjoying this brew for just over a week since I kegged it, and the delicious, pungent aroma and flavour of fresh hops has been fading steadily from day one. Now it’s just barely detectable, and I think we’re about halfway through the keg. Must get better at logging drinks to be honest. Maybe try bottling some of my next batch to see if that’s a better way of preserving the flavour?
Added the second dose of finishing hops just now, 35g Citra again via the top after de-pressurising the vessel. This time there was a substantial buildup of foam as I neared zero pressure and took the lid off, and I think if I hadn’t have thrown in the hops and screwed the top back on quickly there would have been a mess to clear up.
As it stands I may have rushed the refitting of the lid because the vessel wouldn’t hold pressure when the top was back on, so I had to remove it a second time. No issues after re-seating it, keeping pressure fine and back up to 12 PSI. I’m not sure if I should count the cold-crashing as part of the dry-hop duration (though interesting experiments have been done) so I might cold crash a day early and only for 24 hours in order to retain as much of the good hops as possible.
The fermentation curve has levelled out over the past 36 hours so I decided to add the first dose of finishing hops now rather than wait another 2 days as per recipe, which was adjusted (on batch) by reducing the primary fermentation step by 2 days and adding a 3 day cold-crash. The entire collection jar appears to be full of yeast now as opposed to just a quarter inch from just a few days ago, so I’m taking this as another sign that fermentation is done.
Over the past couple of days I’ve been thinking about how to get the most utilisation from my hops (and not have them sitting dormant in the jar) and in the end I decided to close the butterfly valve on all that dead yeast before slowly de-pressurising the Fermzilla and chucking the hops in via the top after giving them a cursory flush with 70/30. The idea here is that once the hops drop down they’ll sit on top of the closed valve instead of in the jar or on the dead yeast, which gives them longer exposure to the beer and minimises any biotransformation to whatever yeast is present above the valve. I can always give it a shake as well without disturbing the yeast in the collection jar, which will hopefully increase utilisation.
This brew went ballistic right after simultaneously pitching an iffy starter and a packet of dry yeast just four days ago, and appears to have been holding stable for almost 24 hours, though the colour is still quite light and has a terrific haze. Think that may have something to do with me forgetting to add the Protafloc – oops!
No matter. I dry-hopped today because I’m confident that it’s going no further in the three days that those hops will be in there, not counting the time I’ll spend cold-crashing. I’m not sure if time spent at 1℃ will count towards the dry-hop time; hoppy beer should be drunk fresh (which makes me think that it does count somehow) but then again if it were that critical we’d be adding hop oils right before drinking, since the cold-crash is at or below regular fridge temperature.
One thing I did differently this time around was to add the hops via the top, removal of which wan necessary anyway since I’d not yet fitted the floating dip tube. The collection jar seems well and truly full of trub and spent yeast, but I didn’t remove it to dump that lot out since I couldn’t be sure I’d closed the butterfly valve fully – didn’t ‘click’ into place horizontally as before so I wasn’t about the remove the jar and start leaking beer everywhere.
In therms of pressure we’ve been at 5 PSI right since the start of fermentation, and I released this quite slowly in order to minimise stress on my Tilt digital hydrometer. I’ve not had a pressure-related ingress into the devise yet (touch wood) but it must be a factor. Once the hops were in I increased pressure very gradually to 10 PSI from the bottle, so that I own’t have to faff about with the bag once we start cold-crashing. Hopefully 10 PSI will be enough …
Added 25g each of Falconers Flight and Mosaic via the bottom jar method after lowering the pressure from 15 to 5 PSI and closing the butterfly valve. No real drama here, just a bit fiddly / messy trying to catch all the drips and undo the jar with the strap wrench.
Hops were added to the sanitised jar as well as two small tubes on the inside to direct the CO2 that was used to purge the jar of oxygen via the side-posts once it was refitted. I tried to open the valve as quickly as possible so that the hops would be distributed throughout the brew, and although they did go for a vigorous swim they soon settled back in the bottom of the jar. I’m not happy with this method as I’m sure it’s not giving me the hop utilisation that I could get via another method. Need to experiment at some point.
Pressure is set for 15 PSI again, though to be fair, blasting in the hops took it to just under 10 PSI as some of the carbonation was released. Temperature going up a notch too, now set at 28℃.
The fermentation graph in Brewfather has been decreasing at a steady rate these past few days instead of tailing off, which is interesting. I wonder what’ll happen for the remaining three days?
The Kveik has been doing a great job here and fermentation appears to have slowed up over the last 36 hours, so I’m going to dry-hop now (day three) rather than on day four as directed. There’s still a layer of Krausen on top the pellets easily go through, all looks good. I hope I’m not too early, but wanted to do this while there’s still some fermentation going on in order to protect against oxidation while leaving it late enough to not loose too much of the hop oils along with CO2 being produced. Sometimes it’s hard to know where to strike this balance, especially as I’m doing something different each time. Gravity weighs in at 1.024 today.
Added the included 10g of Amarillo and 10g of Cascade by opening the brew bucket lid and pouring them on top. Krausen had been and gone but there were a couple of large bubbles still hanging about on the surface, with some occasional small bubbles rising to the top from somewhere beneath. Nice light colour, no iffy smells.
I do wonder if the instructions call for dry-hopping on day four so as to play it safe in terms of oxidisation, relying on the tail-end of fermentation to produce enough CO2 to combat any oxygen that’s introduced by simply pouring in hop pellets, and if a more considered application at a later date would yield better flavour and aroma. Then again it may just be the way that this beer has always been brewed, so I don’t want to tinker too much, but couldn’t resist going one day later with the finishing hops.
I heard about a technique referred to as Hot French Randall a while back and wanted to give it a go, so what better candidate than the American Pale I was brewing with my first batch of harvested yeast?
My dedicated stainless steel cafetière had arrived a couple of weeks previously and Thirst Scratch was coming up for dry hopping, so I decided to split the hops into two equal portions and do the same with the brew, once I’d removed it from the refrigerator where it’s been cold-crashing for a few days. It actually went pretty well with only two hiccups.
The final dose of hops consisted of 25g Citra and 25g Falconer’s Flight, which I’d mixed together and sealed in a vacuum bag when I was weighing out the ingredients right at the start. Today I released the vacuum and gave the bag a good shake, but can’t be 100% sure that the two 25g batches I divided it into each contain exactly the same ratio of both hop types.
There’s a small chance of contamination from the new cafetière because the design features an inaccessible void in the lid which can nevertheless gather water, and it did so during cleaning. I noticed some black sludgy substance on the shaft as I was about to seal in the hops, and decided to wipe it off with some fresh kitchen roll, knowing it won’t be 100% sanitary but having to bow to the lesser of two evils or junk the experiment.
As tests go it won’t be totally clinical anyway because I didn’t add a cafetière of water to the half of the beer which remained in the bucket it was cold-crashed in (so the other half will be slightly more diluted) and I didn’t rack the ‘standard’ dry-hopped treatment to a fresh bucket, which means it’s still sitting in whatever it dropped during crashing.
Both vessels are now in the brewery at ambient temperatures of around 17.5℃ and as they’d finished fermenting I don’t expect their contents to be much above that. The traditionally dry-hopped bucket is a 25 litre plastic FV, the HFR treatment sits in my 10 litre SS Brewtech bucket, which was filled via the bottom spigot using a racking cane after being roughly purged of oxygen via a blast of CO2 from the top.
I decided to carefully remove the Fermzilla from its stand this morning and give the contents a good slosh around, because I wasn’t happy with the way that my hops have been sitting around in the collection jar since they were added.
Thinking about the design of the FV, the jar is a great place for any trub or finished yeast to go because anything in there offers a small surface area up to the liquid above, but that’s bound to work the other way too, when you actually want the contents to be exposed, as with hop pellets. Mine appear to have been stationary in that jar since I threw them in and I was concerned that I’m not going to get the kind of utilisation I’m after.
My suspicions weren’t helped by the fact that about half of those hops refused to budge from the jar while I had the Fermzilla horizontal, lapping the waterline back and forth. There were even some small pockets of gas in the hop-trub which remained there when the FV was righted again, demonstrating just how densely packed that substance was.
Going forward I’m going to see if I can come up with an alternative method to dry hopping. The Hot French Randall approach warrants experimentation, as does addition of flavouring hops in stages – and not letting them settle in an inaccessible crevice.
Final observation: adding hops has restarted some slight fermentation. I closed the spunding valve fully yesterday so that I don’t lose any of the hop-laden CO2 I’m going to produce, and in 12 hours it’s crept up from 7 PSI to 8 PSI.
There’s some very slight signs of fermentation going on and still a bit of Krausen remaining, but I’m going to stick to schedule and remove the trub, then chuck in some hops. Added today were:
93g Falconer’s Flight 11%
55g Amarillo 9.2%
55g Mosaic 12.25%
The procedure was broadly the same as when I dry-hopped Golden Wave just over two weeks ago; reduce FV pressure to 5 PSI, shut butterfly valve, de-pressurise collection jar completely via the fitted carbonation cap and drain as much liquid as possible before unscrewing.
I did a couple of things differently this time around, starting with the gradual reduction of FV pressure from 10 to 5 PSI over the space of 24 hours. I wanted to see if this would help to clear up some of the remaining Krausen (it did, but that may have just as likely been the additional 24 hours too) and because it felt like a respectful thing to do to my expensive WLP001 yeast. Speaking of which, another thing I did differently this time was to save some of that yeast in a sanitised plastic beaker for a reuse experiment over the coming days.
Introducing … [thing]
One last change today was the implementation of a device I’d been thinking about for some time, but I’m not sure what to call it yet, or if even it needs / deserves a name. Basically, flushing the hop-filled collection jar with CO2 before releasing the pellets into the fermenter is a process I’m not 100% happy with, specifically the efficiency balance between retaining as much hop aroma as possible while driving out the oxygen.
Pumping heavier-than-air CO2 into one side of the jar is all very well, but purging it by releasing a valve on the opposite side will probably just let out the same CO2 plus some hop aroma, since the lighter-than-air oxygen is out of range at the top, hiding near the butterfly valve. Today I’m trying to get around that limitation by fitting two tubes to the carbonation caps inside the collection jar, the inlet tube going to the base of my pile of hops, and the outlet tube going as high as it can without interfering with the jar’s seal or the butterfly valve.
My thinking behind this is that I’ll slowly push some CO2 into the base of the jar via that pipe on the left, while the pipe on the right lets out oxygen from the top. I’ve no way of telling if this works since I lack both a control candidate and a dissolved oxygen (DO) meter, but it’s got to be worth a shot. As before, any oxygen that made it into the FV when the butterfly valve was opened is purged via a couple of pops of the pressure relief valve, just in case. Is it worth going to all this trouble seeing as I still have the PRV method? Not sure, and no way to measure. Provided everything is sanitised there shouldn’t be any risks, so why not?
Finally, releasing the hops into the FV by opening the butterfly valve was easy as always, but also the gentlest dry-hopping to date, with hardly any commotion inside. For a few minutes I was concerned that this might not be a good thing, since I want the hop pellets to be utilised as much as possible, but they broke up soon enough and a significant portion made their way to the surface.
On a related note, I read today about a method of adding hop tea created using a cafetière (French Press, as the Septics say) instead of dry-hopping, and that’s something worth experimenting with in future I reckon. Utilisation can’t be worse than dry-hopping (even if you steep below 77 ℃ to prevent isomerisation / bittering) and it should minimise DO absorption too. To be continued …
Been 5 days since the last look at this, has it stopped fermenting? Possibly. Gravity is unchanged if anything, having gained a point to 1.015. There’s practically no airlock activity now, just the odd bubble here and there, and while I’m tempted to give it another couple of days I don’t think it’s going to change. We’re 4 points off Brewfather’s predicted FG of 1.011 and will have to settle for 3.4% ABV instead of 3.9%.
Let’s think about finishing hops. The last extract of this size got 25g Citra, this time I’m going to add 15g of Falconer’s Flight and 20g Citra, for no reason other than balancing my inventory.
Added 25g Citra and 20g Galaxy via the Fermzilla’s collection jar, reducing the pressure and partially draining before disconnection, equalising against the vessel before releasing the hops. One or two challenges were overcome along the way, overall a successful operation.
Removing the Collection Jar
The last time I did this I ended up with quite a mess despite completely de-pressurising the Fermzila before removing the jar. I think it was because I de-pressurised after closing the butterfly valve, which left the collection jar under pressure and a small amount of trub below the butterfly valve yet above the lip of the jar. This was released violently as soon as the jar came off.
Depressurising completely also causes trub to swirl around from the bottom and somehow seems disrespectful to the beer after it’s been sitting there patiently at 10 PSI thanks to the spunding valve, so this time I only reduced the pressure to 5 PSI, shutting the butterfly valve afterwards so that the collection jar too was at 5 PSI.
All I had to do now was see if I could get the trub level down past the rim of the jar before unscrewing it – not really necessary, but I wanted to see how cleanly I could do this. I rigged up some silicone hose to a barbed disconnect and a plastic valve that came with a bottling kit which I never used. 5 PSI shouldn’t be enough to dislodge the hose so I didn’t bother with zip-ties.
The device worked really well, pumping out some thick gunk enthusiastically at first, then more slowly as the pressure inside the jar dropped off. I regretted not fitting a second ball-lock to the opposite side of the jar since the flow was bound to stop soon without air getting in to balance things out, but it carried on dribbling happily until I stopped it after 10 minutes and what looked like 400 ml of yeasty gunk.
Removing the collection jar was as difficult as last time despite me greasing the O-ring with silicone lube before assembly, and would have been impossible without the supplied rubber strap wrench. Even so there’s precious few hand-holds to keep the Fermzilla in place while you wrench away, and you have to be sure to place the strap around the very base of the collection jar in order to prevent the thing from flexing dangerously. When it finally came loose I didn’t spill a single drop of crud, and was pleased to see the level in the jar about half an inch below the lip. Result!!
Refitting and Purging
Having dumped the contents of the jar it’s time to strip off the caps and give everything a steaming hot wash before refitting and sanitising. I’ve not used the collection jar lid before and decide to dig it out so that I can shake it vigorously and foam up some sanitiser, which leaks copiously and I discover that the lid has dislodged the O-ring. Great. Now I have to wonder if it’s been damaged and / or if the same thing will happen when I fit the jar to the Fermzilla. Nothing for it but to add my hops and carefully screw it on while checking with a torch. Thankfully the jar is transparent and I think it looks OK.
I hook up my CO2 to the carbonation cap and dial in 5 PSI, flicking the coke cap repeatedly to flush the jar. I’m not really satisfied with this arrangement; each purge only mixes the oxygen in the jar with CO2, diluting it a little more, but never fully eliminating it. Each purge also takes with it a chunk of hop aroma, which smells very nice but I’d rather it stayed in the beer. Difficult to know where to draw the line, so I go for half a dozen quick purges and resolve to pop the pressure relief valve a couple of times when the hops are mixed in. By then any oxygen will also have gone through the beer, but it’s better than nothing.
#idea: going forward I want to knock up a silicone tube elbow to a second carbonation cap fitted to the collection jar. The silicone elbow should go to the very top of the void, touching the middle of the butterfly valve. I’ll add CO2 via the opposite carbonation cap, slowly purging it via the tubed cap. Hopefully purging slowly will minimise the mixing of oxygen and carbon dioxide, and drawing from the top of the void should give me oxygen first and CO2 later.
Equalising the pressure in the collection jar and the Fermzilla was a good idea. When I slowly opened the butterfly valve I didn’t get the same explosive upward surge as last time, just a gentle mixing of gas, beer, and hops. Move gas disconnect to the top, dial in 10 PSI, pop the PRV a couple of times. There’s no leaks and the hops are well and truly mixed in, as is some of the previously settled matter because the beer is more cloudy and lighter in colour, a bit like it was in the last few days before clearing. Final step is to remove the gas disconnect and fit the spunding valve, cranking it right up. Although I’m sure fermentation was done before I dry-hopped the agitation of yeast and addition of new material could result in some activity, and I want any subsequent CO2 produced to help with carbonation instead of escaping to the atmosphere, taking my precious hop aroma with it.
I couldn’t decide how to best avoid oxygen ingress during dry-hopping, so I carefully poured 25g Citra hop pellets through the airlock bung hole before flushing the headspace with CO2 via a plastic tube inserted a little way. It’s probably not 100% effective since doing so only dilutes the oxygen introduced with the hops, but it’s better than nothing.
Going forward I’m hoping to rig something to the inside of the lid which will allow me to insert the hops right at the start of fermentation. I’ve seen several devices which use magnets to keep the hops suspended in a kind of hammock at the top of plastic fermenters, but that’s not going to work with a metal bucket which you can’t see into. At any rate such a device needs to be airtight until deployment time if there’s any truth in the theory that the CO2 produced during fermentation can take away some of the hop oils as it vents out of the vessel.
The instructions for this kit recommend to add the finishing hops on day four, but fermenting under pressure speeds things up a notch so I decided to take a gravity reading and add the hops if we’re nearing our target FG of 1.014 or below.
Taking a sample via my new picnic tap was an experience – turns out that a gentle squeeze at 10 PSI gives you a very effective foam cannon! Dropping the pressure a couple of notches and opening the tap all the way allowed me to fill an empty beer bottle about ¼ full and then decant that to the trial jar, where taking a reading was also interesting on account of the pleasant carbonation. My first go registered 1.014 but three subsequent dips gave 1.015, so I’m going with that for now. The taste from the trial jar was very good; no off-flavours and a lovely velvety texture thanks to the carbonation, but obviously limited bitterness and no ‘bite’ since I’ve yet to add finishing hops.
Since we’re nearing the end of fermentation and I wanted the hops in there while the yeast was still slightly active in order to carry on making CO2 I decided to dump the crud out of the trial jar and then use that for dry-hopping. There was certainly a load in there – for some days I’d not seen the top of the sediment stack and guessed it was probably way up past the butterfly valve.
Fermzilla’s instructions are quite clear on the fact that the butterfly valve must remain open during fermentation and should not be closed while there’s pressure in the vessel, something I’ve seen repeatedly ignored in just about every how-to video on YouTube. I decided to de-pressurise the whole vessel before attempting to remove the collection jar because doing so with the jar under pressure would almost certainly be messy, and I didn’t have a way of de-pressurising just the jar even if I did feel like ignoring the manufacturer’s advice and betting the brewery floor on that butterfly valve. Letting the gas out of the vessel even gently caused some large lumps of crud to float up from the trial jar before bobbing about a bit and settling back down, a bit like some primordial aquatic monster.
Once depressurised and with the valve closed the jar was quite tricky to remove, definitely need to invest in some food grade tap lubricant before next time. When it did go there was a small, controlled explosion of beige phlegm covering an 18” radius which included my knees, and with considerable disappointment I noticed that most of what was in that trial jar was yeast, with only about a quarter inch of actual trub underneath that. Was that bad? I thought this was a top-fermenting brew and therefore anything lying on the bottom would be dead, but the presence of foam in the middle of the surface, i.e. directly above the trial jar, told me that whatever was down there was still breathing, and now I’d effectively murdered it. Oh well, off it goes into the toilet trub disposal facility.
Once the collection jar was cleaned up and sanitised I removed one of the screw-tops from the side and replaced it with a stainless carbonation cap before dropping the hops in and reattaching it to the underside of the Fermzilla, also sanitised liberally with Star San. Purging oxygen was then a matter of attaching my CO2 tank to the carbonation cap, turning on the regulator to about 3 PSI, and opening / shutting the cap on the other side of the collection jar a number of times. Each of these bursts filled the collection jar with CO2, and each unscrewing of the release side filled the bathroom with hoppy aroma. It’s not a perfect method since each cycle just dilutes the O2 in the jar and doesn’t fully purge it, though I suppose with enough repetition the oxygen would be reduced to near enough zero levels.
But what about the hops? I heard somewhere that if you can smell their pungent aroma it’s because those precious oils are being diffused into the air, which is why you keep them in vacuum sealed bags, in a fridge. Repeatedly blasting them with CO2 and then purging that to the atmosphere probably isn’t the best thing that could happen to the hops, even if each hit decreases the likelihood of oxygenation.
Going forward I’m going to try and improve this method a little bit so that each purge gets more oxygen out of the trial jar, reducing the need for more purges in total. This Home Brew Network video speculates on the possibility of fitting an elbow to the inside of the carbonation cap which then channels the incoming CO2 towards the bottom of the collection jar, but if you think about it, CO2 is already heavier than O2 and will find its way to the bottom naturally, pushing the oxygen towards the butterfly valve where there’s no exit since the exit port is halfway up the opposite side to the incoming port. It would make much more sense to have an elbow tube on the inside of the exit port which ends somewhere near the butterfly valve, since that’s where the majority of the oxygen will be hanging out. Definitely one to try. I do like the guy’s suggestion of using the ‘waste’ CO2 from the Fermzilla to do the purging of the collection jar instead of using external CO2, but that means leaving the butterfly valve closed for extended periods with the vessel under pressure – again contrary to the manufacturer’s recommendations.
Anyway, with the hops suitably purged of oxygen and the jar firmly connected it was time to open that butterfly valve, and boy did those pellets head for he sky. Almost immediately the collection jar was purged of hops and filled with the rest of my yeast, which had settled on top of the butterfly valve while I was messing about with the jar. The rush of CO2 though the brew (I hope it was just CO2) also produced a nice foamy head on top, which was punctuated here and there by dissolving hop pellets. There was just about 1½” of yeast in the bottom of the jar now but it still looked active. In order to test this I pressurised back up to 8 PSI (the dry hopping procedure boosted things to 5 PSI already, mostly through agitation) and let the yeast contribute the final 2 PSI to get me back to my original 10, though at 30 minutes it did take quite a bit longer than it would have before the trub dump. It’s now about 4 hours later and there’s still some foam on top, a lovely green colour, with the brew itself also a shade darker. Let’s hope there’s enough yeast left to finish the job.
Gravity appears to have almost stabilised on Evil Dog; we dropped just 1 point in the past 3 days but the taste from the trial jar has changed over the same time, picking up notes of that ‘sweet & sour’ grassy taste that’s characterised our last attempt at this brew.
Time to get the finishing hops in and then bottle ASAP, so I warmed the two hop bags (1 x 25g Simcoe, 1 x 25g Summit) in some boiled water as instructed for 15 minutes, then tipped ’em in.
It’s only been three days since we started primary, but the rate of fermentation has been dropping rapidly since it peaked 2 days ago, so I added the remaining 30g of Cascade to the vessel labelled ‘DH?’ – the Hoppy one. At first thought 30g seemed a little high and I was going to go with 20g, but there seemed little point in heat-sealing 10g away in the fridge, so I dumped it. Didn’t the Cellar Dweller recently review a beer with 50g of hops per litre? (can’t find it right now, but it’s somewhere on his channel) Anyway, 30g should be fine.
Gravity checked in at 1.016 (3.68% ABV) so it’s a little way off the 1.011 / 4.37% that the recipe predicted, but I figured that if we can drop 28 points in 3 days then our yeast should be able to manage the remaining 5 points in another 3 days. And if not then at least I won’t have bottle bombs to worry about when I put these two away.
The taste from the trial jar was pleasant if a little low on flavour. It’s easy to see why extract brewers often steep some speciality grains when using a light base malt, but given the strongly flavoured brews already on my shelves I don’t mind entertaining an easy-drinking session beer, especially if the finishing hops have their desired effect.
Having spent the larger part of the day pleased with myself at how well this brew’s progressing, I just read a chapter on Extract Brewing in the Big Book of Homebrewing (Christmas gift) and now I have cause for concern, because I transferred the steeped hops to the fermentation vessels when I probably should have filtered them out.
Which of course makes sense. Why would you bring that redundant gunk along for fermentation when you’ve already extracted all the oils that you want? Can’t believe I didn’t question that point in the instructions I blindly followed. I’m tempted to syphon both brews to new vessels (it’s not as though I’m short of 5 litre Ashbecks) but I’m probably going to do more harm now through oxygenation than I’ll do good by removing excess trub. Oh well, a lesson for next time perhaps.
On the positive side, the book agrees with my decision to add a portion of the LME near the end of the boil, which is nice. To be honest I have no idea why I did that, other than to make it easier to mix with the diluting water.
I decided that this cider needed some hops before bottling, because I was impressed by the Mangrove Jack’s Dry Hopped Cider and wanted to see if I could do it too.
Before adding the 50g bag of Citra pellets I’d sourced via Amazon I racked to a new FV because there was a very slight layer of something on top, and because I’d noticed a tiny amount of airlock activity since I measured gravity yesterday. I got to just below 20 litres and was impressed how clear the cider was, and how little sediment was visible on the bottom. To be fair we did rack the vessels we transferred from Port Erin back in November, but still. Very nice. Ambient temperature in the brewery was 19.9 ℃ and I didn’t bother measuring SG again since it won’t have changed much from yesterday.
Almost as an afterthought I filled two 500 ml flip-top bottles before the hops were dumped so that we’d have a comparison, adding 10 ml of Erythritol and three carbonation drops (target = 750 ml) per bottle. I know, over-carbing again, but I really think that two drops isn’t enough for half a litre when it comes to cider, and hope that three drops won’t put us into gusher territory just yet.
Gravity hasn’t moved in two days now and the Krausen as pretty much faded to nothing, so I added the included bag of hops: 50 g pellets identified only as ‘Grapefruit IPA’. Next step is to leave this for 2 or 3 days and then get it bottled.
Checked in on this one and noted that like the Blueberry Cider just now it’s well and truly ready for bottling, let alone hopping. Gravity comes in at an amazing 1.003 (likely 5.91% ABV) which is way below the 1.015 threshold I needed – let’s just hope that my slackness in getting this bottled doesn’t cause too many hints of dead yeast.
Anyway, I tipped in the 50g pouch of Citra hops and then realised I should have added the also included apple essence first, since you’re not supposed to stir the hops once added. Oh well, I’m sure they’ll dissipate on their own accord over the next 24 hours, so I’ll give it a gentle stir then before leaving another 24 hours for the yeast to re-settle.
SG tested at 1.011. Added 30 g Columbus hop pellets, 28 g Citra. Thin layer of foam has settled on top of the brew, nowhere near what was present on Evil Dog or Razorback. I think the difference was that I sprinkled the yeast on top of this one as opposed to stirring it in, like I did with the other two. Must try that again next time, as the result was much cleaner and didn’t get any foam into the airlock. Speaking of which, that was bubbling very slowly before the hops were added, maybe once every 3 minutes though I didn’t measure it accurately. Activity increased briefly after dry-hopping (look at me with the jargon) but soon died off again.
Measured SG at 1.014 (6.69% ABV) and added two ‘tea bags’ of hop pellets as per instructions; Simcoe and Summit. Sample tasted slightly sweet and definitely alcoholic, but will be much improved by the addition of hops and secondary fermentation. Airlock popping once every 90 seconds before adding the hops, briefly increased to once every 20 seconds just after.
Fermentation has slowed on Razorback, just one short burst of bubbles every 2.5 minutes now. The instructions said to add hop pellets (75 g, IPA-specific) 5 days after starting the brew and then ferment for a further 5 days (or at least until it’s stable for 48 hours at or below 1.005) but I heard that you can increase the hop flavour by adding hops closer to bottling, so I added the hops today, technically six days after the start, hoping to bottle in around 4 days. Once sprinkled on top (as instructed, not stirred) the hop pellets increased the rate of bubbling from once every 2.5 minutes to once every 5 seconds. Amazing. Soon dropped back down to previous level though. I took the opportunity to measure SG as well today, and it’s now at 1.016. That’s a good reduction from 1.052 at the start but nowhere near where we need to be, so let’s see what the briefly increased rate of fermentation brings. Rather than returning the sample we tasted it, and while it was flat, warm, and quite raw, it definitely tasted of beer. The fumes from the bucket were noticeably alcoholic too, so it feels like we’re moving in the right direction.