Citra / Rakau PA harsh bitterness / off flavours / ageing

[Cain Harland]

I have just started pouring a rebrew of my Zombie dust (all citra) clone the only difference in the recipe is this time I added 50g (40L brew) of rakau late. The last one was bottle conditioned and this is kegged. This one is a fair bit lighter in color but doesn't taste right. It has a sharp bitterness like tonic water or rubber which seems to be subsiding noticeably during the few days its been in the keg.

The last one according to my notes I couldn't fault but wasn't excited about to start with but it aged really well the citrus fading a bit and a lichee or Mellon type fruitiness devloping. I found that strange as PAs are generally best fresh but really liked it. This one doesn't seem to have much of a citrus or fruit character.

I was initially thinking autolysis but there shouldn't have been time for that. It had 2 week ferment then 2 week cold crash, racked to keg forced carbed at 30psi for 2 days then dropped to 10psi.

Any ideas where I went wrong? Is a 2 week cold crash too long for beer to sit on dry hops? I'm wondering if a couple of weeks aging might help and if I should take it out of the keggerator and age at say 18 degrees to speed things up.

I also crused a bit fine and got the closest to a stuck mash I've had so tannins are a possibility.

[Cain Harland]

Here is the recipe

Citra Rakau
14-B American IPA

Size: 40.0 L @ 20 °C
Efficiency: 76.4%
Attenuation: 78.7%
Calories: 215.77 kcal per 12.0 fl oz

Original Gravity: 1.065 (1.056 - 1.075)
Terminal Gravity: 1.014 (1.010 - 1.018)
Color: 12.18 (6.0 - 15.0)
Alcohol: 6.73% (5.5% - 7.5%)
Bitterness: 73.0 (40.0 - 70.0)

Ingredients:
9.5 kg (81.9%) Gladfields Pale Ale - added during mash
0.9 kg (7.8%) Munich Malt Type 1 (Organic) - added during mash
0.4 kg (3.4%) Melanoidin Malt - added during mash
0.4 kg (3.4%) Caramel Malt 60L - added during mash
0.4 kg (3.4%) Cara-Pils® Malt - added during mash
30.0 g (6.1%) Citra™ (12.0%) - added during boil, boiled 60 m
60 g (12.1%) Citra™ (12.0%) - added during boil, boiled 15.0 m
60 g (12.1%) Citra™ (12.0%) - added during boil, boiled 10.0 m
60 g (12.1%) Citra™ (12.0%) - added during boil, boiled 5.0 m
40 g (8.1%) Citra™ (12.0%) - added during boil, boiled 1.0 m
25 g (5.1%) rakau (10.8%) - added during boil, boiled 1.0 m
40 g (8.1%) Citra™ (12.0%) - steeped after boil
25 g (5.1%) rakau (10.8%) - steeped after boil
155 g (31.3%) Citra™ (12.0%) - added dry to primary fermenter
0.0 ea Fermentis US-05 Safale US-05

[Grant R Baker]

Tannins don't fade quickly... so you have a real puzzler here. I have more questions and a single answer..

 

How was the numbers on the brew day compared to previous..?

Hops from their normal source, same batch or close enough..?

Rakau is a really gentle hop flavour so I doubt it is that.

That is a lot of hops but not unheard of... did all the hop matter go into the fermenter..?

Did the fermentation get above 22C?

Lastly the colour on the brew might be the biggest clue, that is most likely to be a malt... have a chat with the shop you sourced the malt from to find out if any of them have change (this does happen).

 

[Cain Harland]

Efficiency was higher. A bit low on temp both mash. Same hops. Some in the fermenter but left a lot in pot and hop spider. Temp controlled at 18 for ferment.

[Grant R Baker]

Wow ye have me stumped. Mix up on the malt..?

[Cain Harland]

Cleaning the beer lines seemed to help a bit. Not that they should have been dirty I pushed a few liters of sanitizer through just before kegging but I used liquid line cleaner today.

[Cain Harland]

Same issue again different beer. Good news is the sharp bitterness mostly aged out of the first one. Dry hopped after 1 week, cold crash after 2 keg after 3. Crushed a bit coursed this time and got a more free flowing mash.

Still wondering about tannins. I sparged till kettle was at pre boil volume, I have always done that and never had this problem but I do have a new mash tun so its possible things are different.

Quinine is the closest I can get to a description of the taste and even thats not quite right. There's non of the dryness I would associate with tannin.

The other possibility I have thought of is I have started using gelatin to clear the beer after cold crash and shaking the fermenter to mix it in so its possible thats been disturbing the krausen stuck to the sides.

[Cain Harland]

Both these kegs I force carbonated at 30psi rocking them on my knee. Maybe something to do with carbonic acid? I did another keg of this one which is still carbing up slow at 10psi had a taste its still pretty flat but it didn't seem to have as much of this flavour hard to tell maybe its something thats accentuated by carbonation.

[Cain Harland]

So another update. I was a bit worried about over carbonation/ carbonic acid so I pulled the pressure relief on the kegs and let a lot of the C02 out and left for a while before turning the gas back on. I don't think it was over carbonation (I have made my share of over carbonated beer) but it made a huge difference and this new one is starting to taste real good, the off flavor disappeared almost over night and is improving by the day.

I almost tipped 2 kegs of this beer down the drain, it was that bad, but now I'm looking forward to drinking it. I'm still not at all sure about the cause but I have a few things to try differently and something that seemed to help fix it is it happens again. Mostly just slow carbing at serving pressure and stiring rather than shaking the gelitin in to avoid mixing the scum from the sides back in.

One thing I'm thinking about is dry hopping a bit earlier, I've always waited until primary fermentation was well and truly over (usually dry hop somewhere between day 7 and 13, cold crash on 14, add gelatin 15 or 16, keg on 21) but have read some opinions about adding late in the active fermentation (like when the bubble slow down) is scrubbing some of the unwanted flavors and leaving the good ones. I'm wondering if my releasing the pressure had a similar effect as a little fermentation, that is the CO2 taking some unwanted dry hop flavor with it, the only thing that makes me think that maybe that isn't the case is knowing people have good results dry hopping in the keg.

When do others dry hop?

[Nathan]

7-10 days MAX and this includes crashing longest I have crashed is 4 days, Dont see the point in crashing longer if your kegging

[Cain Harland]

Do you recon there's any harm in leaving the hops in for a long crash?

My schedule basically revolves around weekends so if I primary for 2 weeks (wouldn't want to be any less) and crash at all its going to total 3 weeks so shorter crash would mean longer primary, which may not be a bad thing.

[Cain Harland]

So assuming its in the fermenter 2 weeks or more your defiantly crashing after active fermentation stops which is what I'm most interested in.

[Nathan]

Im a weekend brewer too so i crash around day 10-11 dry hop day 7 and keg on day 14-15, have been known to crash on day 13 in a pinch