Sad to see this one go, but it was great until the end and I’ll do it again, possibly with cheaper yeast and a more efficient way of dry-hopping. Incidentally it’s been 41 days in the keg(s) and was as fresh at the end as it was at the start, which is great to know.
Put away between 22 and 23 litres today, mostly filling a 5 litre mini keg and a 19 litre Cornelius. No real drama as such; this time I remembered to flush the filter line with CO2 after sanitising it and again I did the same with both kegs, so I’m looking forward to a really hoppy number with no oxygen contamination. Again I used the fully-closed system, feeding CO2 from the keg back up to the fermenter once I’d popped the PRV to get things going, but this time I didn’t drop the pressure in the Fermzilla (which had gone from 7 to 12 PSI since dry-hopping) instead matching it by increasing the keg to 12 PSI also.
On the subject of filters, I’m using the Bouncer again but this time with the finest mesh, which I had to order specially. It kept behind a fair bit of hop matter but we’ll have to see how good it really is when I draw off the first pints from those kegs. Admittedly it’s not going to be a true representation of the filter’s ability since I didn’t cold-crash the Fermzilla this time, so I expect there to be a fair bit of crap in the bottom of each keg just from crashing. One final note where the filter’s concerned, and I’m not 100% happy with the fit of the replacement element, it’s just very very tight and ended up being skewed slightly when I screwed the filter closed. Will have to see how that works in the long run – might be OK, might be its first and last outing.
One thing that was slightly disappointing (or rather it will be) is the hop utilisation, which I’m guessing is going to be nowhere near what I want. When I removed the collection jar at the end of transfer there was an almost solid green lump of lovely hops in there, full of gorgeous pungent aroma. They even stayed put when I turned the collection jar upside down, so how on earth have they imparted their goodness unto my brew? Maybe dry-hopping is better for flat-bottom fermenters, maybe there’s a reason after all why so many stateside brewers rack to secondary. I don’t know. I do know that I’m going to try the Hot French Randall (HFR) method a go next time around, and have ordered a 1 litre double walled cafetière specifically for this purpose.
Another thing I’m going to have to order is a new collection jar for the Fermzilla. After I tipped out the semi-used hops I reassembled it loosely in order to soak it in PBW, and I forgot the manufacturer’s advice about not using the two ports for leverage. I’m not normally too ham-fisted and like to think I’ve got a good level of mechanical sympathy, so I was rather surprised when one of my stainless carbonation caps came off in my hand, taking a chunk of plastic with it. Oh well, live and learn.
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 …
Twisty Listy has surpassed target FG of 1.008 with 5 days still to go and is presently sitting at 1.005, which will give 4.3% and pushes the limit for a session IPA in my opinion. But that’s not the main cause for concern.
No, I’m more worried about the unusual amount of Krausen that’s still hanging around. There’s been no change in the beige blanket of snotty foam in 5 days now, and I’m used to seeing it clear up when the bulk of fermentation is done, so probably around 6 April on the graph above. There’s obviously still life in the yeast because FG keeps edging lower, but I’d be more comfortable if the Krausen receded too. Not that there’s anything I can do at this stage, will just have to write it off to a learning experience using this new style of yeast.
Fermentation seems to have slowed up visibly ever since I added pressure three days ago and the gravity chart in Brewfather has been flattening out at 1.012 for 24 hours, a good way off the 1.008 FG I was expecting for an ABV of 3.8%. Admittedly we’ve still got 10 days left to run (not allowing for short-cuts due to pressure) but there’s also quite a bit of Krausen still present and I’m used to that being gone when fermentation’s apparently over.
On a positive note, clarity is very good with just about everything having dropped out of suspension and the brew has reverted back to a lovely dark gold colour. Wish there were some more small bubbles though, it’s just clear brew sitting beneath an ominous layer of Krausen.
It’s just dawned on me that not only is the temperature inside the FV dropping off with reduced activity, we’ve also been experiencing an unusual cold snap these past few days; three days ago we’re hiking in T-shirts now it’s snowed overnight for the second time and the pond’s frozen over. The wind direction hasn’t helped either, with north-westerlies blasting arctic air straight at the brewery. Room temperature is 18.3℃ and for the first time since starting this brew I’m getting the same reading from the Tilt, and since we’re aiming for 19℃ inside the vessel it’s probably fair to say that some of the reduction in activity could be down to temperature. Switching on the towel rail for a few days, moving SS Mini Bucket (Foxdale Gold) outside.
I really need to get myself a fermentation fridge set up, there’s no way that beer quality can not be affected with the vessel bouncing between 23 and 18℃.
The temperature has been increasing steadily with fermentation and sunny weather. I was hoping to keep it around 19℃ which is the optimum for the WLP001 yeast I’m using (range: 19 – 21℃) and really need to get myself a fermentation fridge so that I can control this better. This beer doesn’t really need esters and it certainly doesn’t need fusel alcohols, so I’ve no hesitation in applying some pressure to the fermentation after 24 since kick-off.
Speaking of fermentation, it’s not been a quick starter, with the first signs of life in the airlock showing maybe 4 or 5 hours after pitching both tubes of liquid yeast. I was beginning to get worried; one of the ice packs that accompanied the yeast on its voyage over to us had become punctured by something else in the box, and I had doubts whether or not the yeast had really been kept at 4℃ all the way as intended. Things did start happening that evening, and by morning there was a thin layer of foam on top, maybe ¼ inch thick, with the usual frenzied activity going on underneath.
By noon that had increased to almost an inch, and when we came back from an afternoon walk we swapped out the airlock for a spunding valve set at 10 PSI. This had a dramatic effect on the foam, which transformed into a thick Krausen over the next few hours, almost touching the vessel’s lid by evening. To save the spunding valve I decided to move it to a spare keg and then connect that to the Fermzilla with a blow-off tube, but forgot to pre-pressurise the keg and caused much of the Krausen to head straight down the tube as soon as it was connected. I removed and cleaned the tube just in case, must remember to do the same for the Fermzilla’s PRV once this is done.
My second ever AG brew day, and this time it went much more smoothly than the first, with one tiny exception: I was 6 litres down after the boil and decided to add 5 litres of Ashbeck in order to get OG and fermentor volume into the ballpark. As always when I’m making these entries at the end of a long brew day, I’m too tired to post-rationalise the figures into some sort of sense, so I’m going to reward myself with a first taste of Golden Wave (still technically conditioning, but what the hell) while I ponder some salient points:
- Six litres. WTF?
- I measured my system’s capacities and boil-off loss two days ago, they’re very well aligned with Brewfather’s defaults. That’s good.
- Fermentor top-up was probably the right thing to do, even if it was a staggering 5 litres. Apart from getting me exactly to my target volume, would adding that sixth litre have also given me my target OG? Feels like it. I’m one point high and one litre low @ 1.038 / 24.
- Hope that expensive White Labs liquid yeast is fit for the job. One of the two gel packs which accompanied it on the 3 day journey over to us was punctured (but did a great job chilling the rest of my order) and I’m worried that the two sachets may not have been kept at exactly 4 ℃ as they claim to need.
- Hope the Tilt Pro is not going to take on water. I had some minor signs of ingress after the last brew, nothing major, just past the seal and up the thread, and it seems to be OK after applying some silicone grease to the seal. Pressure tested OK yesterday at 20 PSI in water for 12 hours, but still. Worried.
- Good brew day. Mash had a great consistency and felt like I got everything from the grain that I needed. Sparge still very quick at six minutes, I can probably stir the mash a bit less towards the end and worry less about compacting the grain bed into a stuck sparge, instead filtering out more grain particles.
Brew Day Notes
- Heating mash water from 13 ℃ mains temperature to 66 ℃ strike temperature takes same amount of time as it takes to make and eat 2 slices of toast. Impressive. Add chemicals once it’s there.
- 10:53 Start dough-in
- 11:03 Dough-in finished, start 20 minute timer for rest before mash proper. Only the slightest touch was needed to get all grains covered in water. May as well pull out the aeration kit since that’s behind the MLT and will be difficult to get to later.
- 11:22 mash timer started, give it a stir and start gentle recirculating through centre pipe + around malt pipe. Mash feels much looser than last brew, really easy to stir and no lumps. Little bit of foam though – due to chemical additions? Acidulated malt? No idea. Core temp 67.4 ℃ – looks like setting the thermostat at 68 in anticipation of insulation wasn’t necessary – decreasing to 66.
- Stir after 10 minutes, still light with no tight spots. I’m playing around with different pump speeds and trying to maintain a little fan of sparge water from the centre pipe without letting the level drop too low outside the malt pipe. All good fun. Got the lid on between stirs in order to make cleaning up easier – wort splashes are sticky and travel further than you’d think!
- 35 minutes to go. Not much happening, just stirring once every 5 – 10 minutes, trying to keep the level outside the malt pipe within 2 inches of the inside, mostly succeeding. Only sucked in air briefly once when it got too low, good job I’ve the dip tube higher than the elements. Each time a stir is coming up because the level gets too low I notice that the clarity outside the malt pipe is great, much better than at any other point. I’m thinking of performing a mash-out before sparging to see if I can get the clarity back and raise temperature a little ahead of the boil. Who knows, if the viscosity increases I may even have a smoother sparge but, then again, I could end up compacting the grain bed to a point where it will be more difficult to get sparge water through.
- 3 minutes to go, one last stir before increasing temperature to 77 ℃ and mash-out. Started to suck air a moment ago, now there’s foam on the wort. Hope it’s due to the air and not something more sinister.
- 12:53: mash timer up, setting temperature to 77 ℃. Might take a while to get there as I’m in Mash heater mode and the elements are limited to (I think) 50% to stop scorching.
- Bit more air being sucked now and then, flow adjusted so it’s barely going through the malt pipe in order to keep the dip tube fed. Outside level obviously low, but also clear. The bit of wort that is going onto the grain bed has particles which I know wont make it out again, but it’s also going to compact the grain ahead of sparging. Hmmm …
- 13:03: Pump temperature 72.1 ℃, mash at 70.4 ℃. There’s now just a dribble going through the grain bed in order to stop the dip tube sucking air. At least the outside wort is clear!
- Sparge water standing by at 77.5 ℃, raising the malt pipe prior to sparging.
- Bit of vorlauf to wet the grain bed while I get a wort sample from on top since I can’t get the baster down the side.
- Sparge started 13:12, only brief burst from pump then wait while inch on top of grain bed recedes.
- Much more confident about this sparge than the last one. Water on top of grain bed is clear, drains just fine. Discover it is possible to get a fan with pump around 50% and HLT tap open, nearly get face burnt off.
- 13:18: sparge water out. I won’t tilt the HLT to get the last drops since it was calibrated with dead space. Damn, that went fast again, six minutes!! And to think I’m always worried about a stuck sparge. Leaving it to drip for a while, might as well start recirculating the wort (without using the centre pipe) and get the heaters back on while I measure the pre-sparge / post-mash sample: 1.047 @ 45.6 ℃ which converts to 1.056.
- According to internal scale I’m a touch below 28 litres, maybe 27.75, malt pipe removed. Post-sparge sample was taken, waiting for it to chill before attempting a reading. Scared as hell my glass baster would shatter as I touched 77 ℃ wort. All good. Heater back in auto mode, climbing to 90 ℃ with pump whirlpooling at 30% while I fit the steam hat and condenser.
- Limit of 90 ℃ in Auto mode reached after 12 minutes from 77 ℃, some slight thin white foam but no boil yet. Switching to manual, giving it 100%.
- 13:56: 100 ℃ indicated, some signs of boiling but you wouldn’t call it ‘rolling’ just yet. Pump to 25%, condenser switched on, timer started.
- 14:00: Now it’s a rolling boil! Scaling power back down to 85%, see if it maintains. IIRC the Brewfather default equipment profile contained a comment about boil-off having been measured at 70%, so we’ll see if we can get down to that and still maintain a boil.
- 14:10: Still boiling as it was 10 minutes ago, reducing power to 75%.
- 14:20: Still boiling perfectly well – not quite as ferociously but boiling, indicated 100 ℃. Reducing to 70%.
- 14:30: 60 minute boil additions are in, still boiling well but the output from the condenser is cooler which means there’s less steam being produced, so less boil-off. Looks like I’m at about 26.5 litres on the internal scale, for what that’s worth. Fermenter target volume is 25 litres and IIRC my hardware profile has 2.4 litres trub / chiller loss, so this should be interesting. Then again, the internal scale didn’t align with my measured values too closely when I updated the standard hardware profile, so I’m not going to worry too much about it now.
- Pre-boil gravity 1.038 @ 23.5 ℃, converts to 1.039. Brewfather thought I was going to get 1.033 so I’m 6 points ahead – nice!
- 15:12: Added my 15 minute boil addition, 1/3rd tablet Protafloc.
- Started circulating through chiller in order to sanitise, initially with l/h valves to 50% chiller, 50% short re-circ, then 100% chiller once the bubbles had gone. Heaters back to 100%.
- Temperature (pump) briefly dipped to 96.5 ℃ but climbing slowly. Pump at 15% since we just want to sanitise the chiller and not chill the wort just yet.
- Heaters back down to 75% as a rolling boil is achieved moments later.
- With the recirc / transfer pipe temporarily out of use while I sanitise the chiller I take the opportunity to fit my aeration setup to the upper l/h valve.
- 15:28: heaters off, time for the 0 minute boil additions. Steam hat off too, and wow, it looks like we’re down to 23 litres if the internal markings can be believed. I do hope not, was aiming for 25!
- Whirlpool started 15:32, tank temperature 96.6 ℃. I don’t know how long to leave 0 minute boil additions, but the name suggests that there’s no boiling to be done once they’re in. But I’m still expecting some isomerisation of hop oils since we’re above 77 ℃. Not sure what to do. Let’s give it 5 minutes and then start chilling.
- 15:39: starting chill. We’re at 89.4 and there’s still quite some steam coming off.
- 15:53: return temperature is down to 23.2, tank 34.9. Time to start filling the Fermzilla with aerated wort.
- Holy crap! I’ve just 19 litres but 1.048 OG when I should be looking at 1.037. That means I will end up with 5% ABV!
- Adding 3 litres of Ashbeck brings it to 1.042 (4.5% ABV) so I decide to go the whole hog and tip in the remaining 2 litres, making for a total of 5 litres fermenter top-up and 1.038 OG.
- 16:35: Pitched both packs WLP001, deployed Tilt, retire to safe distance.
- Clean-up finished 18:14. Big shout out to the Hozelock / TC34 adapter that came with the steam condenser and allows you to hook a standard hosepipe connector up to any 34mm Tri-clamp port. When I’m not using it to drive the condenser’s cold water jet during boil it comes in very handy for flushing out the chiller, pump, and all plumbing with clean water.