A20 citrus and WLP644

Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum

Help Support Homebrew Talk:

kye77

Active Member
Joined
Jun 6, 2016
Messages
28
Reaction score
4
Location
Orlando
Does anybody have any experience with Imperial A20 Citrus and/or WLP644?
I'm curious to know what temps works best in YOUR experiences and what types of beers work well with these "Sacc Trois" type yeasts.
Also, Id be happy to learn more about this strain if you have any other inputs.
Thanks :]
 

wmcc75

Well-Known Member
Joined
Jul 21, 2013
Messages
291
Reaction score
45
Location
Columbia
Never used the a20 but 644 and warm temps, I've used it into the 80s before, make for some awesome citrus and almost (to me anyway) mango. I use it in a single hop Amarillo ipa and really like it. Keep in mind it attenuates more than other yeasts so don't go too crazy with bittering hops.
 

emsroth

Well-Known Member
Joined
Feb 19, 2012
Messages
82
Reaction score
5
I have used it in classic IPA and contemporary tropical IPA. Shines in both. 70F and 75F respectively.

I jus made a nice little American blonde ale. Mashed at 152. Fermented at 67. It's currently cold conditioning, but from what I taste it's just okay. The yeast doesn't highlight malt flavors and the tropical notes are out of balance without the hops. I brewed this beer specifically to test the limits of this yeast. So we'll see in about a week.

The slurry from the blonde will go to prop up a big DIPA - Vienna malt base with Amarillo and Simcoe.

I am most curious about how it plays with dark malts, like a funky stout or a black IPA.
 

emsroth

Well-Known Member
Joined
Feb 19, 2012
Messages
82
Reaction score
5
The other characteristic of this yeast I al learning is that it fights with wheat, or so it seems. I had extra wort and used it as a starter for this yeast, and the 25% wheat in the grist made the beer taste like a bad brewpub hefe. The blonde ale also has 10% wheat, and I am picking up some of those same flavors.

I have a 50% wheat mosaic IPA planned this summer, so that will be the tell.
 

brewmeister13

Well-Known Member
Joined
Feb 11, 2013
Messages
568
Reaction score
59
Location
Tucson
I've brewed with both, but never in a comparable recipe. I'm actually planning to use A20 in a recipe I brewed with WLP644 that was a major hit to see if I like it as much (way less work starting with 200 billion cells than 8 billion). It won my local club only, people choice, competition a few years back and was brewed on a 15 BBL system. I like to add 1 mL of lactic acid per gallon of wort at post boil. Not sure if this yeast possesses the biotransformtive properties to transform lactic acid to ethyl lactate (my controlled experiment was a loss to test this when I let a couple air locks run dry), but it seems to work really well. I also agree with warmer temperatures. I like to start lower, 65 or so, and let it ramp up like a saison. I also really like Citra with this yeast, but only as part of a blend.

The other characteristic of this yeast I al learning is that it fights with wheat, or so it seems. I had extra wort and used it as a starter for this yeast, and the 25% wheat in the grist made the beer taste like a bad brewpub hefe. The blonde ale also has 10% wheat, and I am picking up some of those same flavors.

I have a 50% wheat mosaic IPA planned this summer, so that will be the tell.
I'm not sure I would blame that on the wheat, the above mentioned recipe used 22% wheat and it turned out really well. Have you had success without wheat? If so, did you change anything else?

I am most curious about how it plays with dark malts, like a funky stout or a black IPA.
Not good, at least in my very limited experience. Seems like it would be awesome in a hoppy stout, but it was really bad. It clashed with the roast and muddled up the flavors.
 

emsroth

Well-Known Member
Joined
Feb 19, 2012
Messages
82
Reaction score
5
For the most part, I've had nothing but success with this yeast. I'm just trying to nail down a solid house yeast for the upcoming brewery. I'm hoping it's not a one-trick pony (IPAs). But I really like what it does with them, so that's fine by me.

The beer I was going to brew would be a black IPA, so light on the roast malt. Less than 5% of chocolate and midnight wheat. I'll split the batch between the Brux Trois and Conan. Too many yeasts and not enough time.

My house IPA uses all classic hops (Willamette, cascade, and centennial) and it plays really well with those. Of course it goes great with the new wave hops.

Regarding the wheat, I just get the feeling that the "starter beer" wasn't good because of fermentation control more than the wheat. And the blonde ale was probably just too yeasty which I am foolishly attributing to wheat (think hefe). The blonde ale has since been fined and cold crashed, so we'll see this week when I re-tap.
 

emsroth

Well-Known Member
Joined
Feb 19, 2012
Messages
82
Reaction score
5
Update:

Blonde ale cleaned up in terms of flavor but remained boring. A dose of centennial and comet dry hops helped it pop and was quite a hit.

I have two beers fermenting right now.

1. Aclassic American IPA with Columbus and chinook. Fermenting at 68F. 3 days in its dank and tasty.

2. An experimental IPA. Pitched at 70 and rose to 75 by the end of day 1. I noticed a cidery note (perhaps from the simple sugar). Now on day 3 it is heavy with banana. I am afraid i let the temp ramp too early. Pitch rate was solid at 0.75 M/mL/P with an even split of fresh yeast (can) and slurry. OG 1.066.

All I can do now is pray to the beer gods that the flavor subsides by day 7. If not, I'll buy a fresh pitch and try again. Luckily the beer has only an ounce of bittering hops and then a bunch of dry hops, so I can hold off on adding them until the flavor settles.
 

thehaze

Well-Known Member
Joined
Jun 28, 2017
Messages
2,194
Reaction score
988
Location
Iasi, Romania
I am at the moment fermenting a Red IPA using WLP644 at about 78-79 F. So far, it smells intense.

The beer will come out at around 7.2% ABV, 50 IBUs, SRM 16. For hops I went with Denali, Yellow Sub and Au35 ( https://www.themaltmiller.co.uk/index.php?_a=viewProd&productId=2760 )

First time using this yeast and I hope it turns out great. I have read good things about it.

I will be sure to post any results I get from this beer.
 

tiredofbuyingbeer

Well-Known Member
Joined
Sep 5, 2016
Messages
231
Reaction score
41
I've used the A20 Citrus a few times. For some reason, my LHBS only carries Imperial Organic yeast (a great product, btw).

I love this yeast. It smells awesome when fermenting. I usually pitch at 70 or 72 and ramp up after a day or two. I just let it go free as long as it stays below 78, but I'm sure it'd be fine in the 80's even.

I'd really like to try this with different beer styles. I've thought it might be nice to try with a blonde or a porter. Or maybe a non-fruit smoothie IPA

Note: It attenuates heavily.
 

emsroth

Well-Known Member
Joined
Feb 19, 2012
Messages
82
Reaction score
5
I can say with experience it's boring in a blonde ale. I needs dry hops or perhaps a long cold aging to drop bright.

I am curious about a black IPA because it's dark and would satisfy the hop needs of the yeast.

Other reports (maybe even the beginning of this thread) are that the yeast clashes with dark malts.

I just made an American Amber with toasty pale ale malt and Crystal 40L; in the fermenter it is quite bready, chewy, and delicious. No clash with the toast. Next stop is a hoppy brown ale. Slowly working my way darker and darker.

Further update on the banana esters - I think this yeast just produces a slight hint of banana that melds with the tropical fruit and is covers by high hopping. It may also be a flavor produced in the green beer that ages out.
 

emsroth

Well-Known Member
Joined
Feb 19, 2012
Messages
82
Reaction score
5
Made my way to an American Amber with a percent or two of chocolate malt for color. I can say right now (2 weeks after brewing, 5 days after Kegging) that the finish is strong on roast for having so little. Perhaps because it's not balanced by Crystal or bready malts. The hops are fantastic (as always).

I will still try full American brown, but light on the roast.

Follow up on the Crystal malt beer above, came out quite sweet. I am beginning to believe that this yeast has the attenuating power of Wyeast 3711 but without the ability to cut through sweet worts.
 

marjen

Well-Known Member
Joined
Feb 9, 2017
Messages
747
Reaction score
187
I just got some a20 and a24 in. It was shipped and showed up warm. It did have ice packs in it, and arrived in under 48 hours hoping it's ok. Guess I won't know until I pitch.
 

Desertbrewer

Well-Known Member
Joined
Oct 19, 2015
Messages
100
Reaction score
23
Got an NE style mosaic/citra pale with A20 in the fermenter. Intended on it being a normal gravity IPA but really undershot my efficiency; oh well. Curious to see how estery it comes out due to the fact that Imperial gives you 200b cells, and my gravity is only like 1.043. Should be good regardless. How much are all yalls beers attenuating?
 

emsroth

Well-Known Member
Joined
Feb 19, 2012
Messages
82
Reaction score
5
Attenuation has been an interesting story.

Imperial Yeast says 74-78%

White labs (WLp644) says 85%

I consistently got 85%. Then one time I got 100% in a double IPA. I use simple sugar often, but not always.

Recently I had all-malt wort start at 1.049, fresh can of yeast, no starter which got me to 0.5 M/mL/P, and the beer finished at 75% AA. Lower than anticipated.

I have observed with many yeasts that if your first beer contains simple sugar, the yeast learn to ferment a high level of AA and continue to ferment to dryness in subsequent generations.

My next beer with the 75%AA colony of yeast will have lots of honey in it, so we'll see how it turns out.

So if it's all malt, assume 76% and you'll be fine a little over or under.

If you have simple sugar, assume 85%.
 

g-star

Well-Known Member
Joined
Feb 28, 2010
Messages
869
Reaction score
163
Location
PA
Resurrecting an old thread, but does anyone have experience on how long it typically takes A20 to reach FG?

Brewed a NE style IPA, no simple sugar, no crystal malt, mostly 2-row and some oats/wheat. Mashed at 152F, OG 1.064. Pitched a healthy starter at 68F and fermented around 72F during high krausen. Took off like a rocket, but seems to have completely crapped out after about 48hrs, and gravity is hanging around 1.022. I have swirled the carboy and increased the temp to 76F.

Any similar experiences?
 

emsroth

Well-Known Member
Joined
Feb 19, 2012
Messages
82
Reaction score
5
The only time I have had issues with this strain is when I did a trub dump 24 hours into it. The beer stalled at 1.03x. I added a slurry I had on hand and got it down to 1.012. This yeast seems to hang out at the bottom. Not much krausen ring in the fermenter after fermentation.

This yeast also benefits from additional pitch rate. I would go 1.0 Mil/mL/P rather than typical ale 0.75.

1.0 for beers under 1.060 OG; 1.25 for beets 1.060-1.080; and 1.5 for 1.080 and above.

I use this strain exclusively for IPAs. The Imperial A20 will actually stick to the published AA data if used fresh on a typical wort. Using 10-15% sugar in the first generation can get it to 85% AA. Otherwise sugar will get it closer to 82% AA.

Sour beer Brewers (and patient Brewers) extremely underpitch and let the primary go for 5 weeks.
 

g-star

Well-Known Member
Joined
Feb 28, 2010
Messages
869
Reaction score
163
Location
PA
Thanks for the reply. I did shoot for a pitch rate of 1M/mL/*P. Maybe I just need to give it more time, but it activity has really almost come to a complete stop.
 

emsroth

Well-Known Member
Joined
Feb 19, 2012
Messages
82
Reaction score
5
I'm sorry to hear that.

Since using this strain I have been using pure oxygen as well. 60 seconds for up to 1.060; 90 seconds for 1.060 to 1.080; and 120 seconds for 1.080 and above. I use benzomatic canisters and a 0.5 micron stone. The regulator has no gauge, so I open the valve until I observe flow, and then dial it back until there's a small stream of bubbles.
 

emsroth

Well-Known Member
Joined
Feb 19, 2012
Messages
82
Reaction score
5
Thanks for the reply. I did shoot for a pitch rate of 1M/mL/*P. Maybe I just need to give it more time, but it activity has really almost come to a complete stop.
Funny you posted. I just checked my house IPA, fresh batch of Citrus A20 dated 1/23/2018, direct pitch into 1.054 for an effective rate of 0.63 M/mL/P, and after 6 days it's only down to 1.015 (71% AA). Main ferment at 72F, raised to 75F at day 3, now up to 78F to hopefully finish.

This has been a great yeast but definitely inconsistent.
 

g-star

Well-Known Member
Joined
Feb 28, 2010
Messages
869
Reaction score
163
Location
PA
Thanks for the replies. I did also oxygenate with pure O2 for 75sec as described in post #26. After warming to 76F, swirling, and holding for 4 more days, gravity never budged from 1.024.

I ended up getting a fresh pack of WY1056, made a 1L stirplate starter, and pitched that at high krausen. Activity in the beer picked up right away and it attenuated down to 1.012 in 3 days.

Verdict in my opinion is A20 failed for one reason or another, though I did everything right in terms of starter, pitch rate, pitch temp, ferm temp, and oxygen levels. Makes me wary of using it again, no matter what flavors it may bring to the table.

TBH, I have had some bad experiences with these "boutique" yeast companies like Imperial Organic and ECY. Wyeast and WL have always been rock solid in terms of meeting expectations.
 

emsroth

Well-Known Member
Joined
Feb 19, 2012
Messages
82
Reaction score
5
image.png
I feel like I've had the most trouble with White Labs.

Imperial only let me down once, but that was from under pitching most likely.

When imperial first began, I was told they have good customer service. They would replace cans for bad batches. I think they are too big for that now.

Imperial and Omega have most of the same strains as everyone else. I thought I had something special with their "Darkness" strain until I realized it's Guinness. Take a look at the attached photo for reference.

Send them an email as see what they say. They may have advice for that strain.

Cheers and best of luck. Post a pic of the finished beer.
 

Jason Stockdale

New Member
Joined
May 9, 2019
Messages
1
Reaction score
2
Does anybody have any experience with Imperial A20 Citrus and/or WLP644?
I'm curious to know what temps works best in YOUR experiences and what types of beers work well with these "Sacc Trois" type yeasts.
Also, Id be happy to learn more about this strain if you have any other inputs.
Thanks :]
Looks like they answered the initial question. But a caveat would be I have noticed this strain will do way more than its advertised directions. For one it will finish several points lower than most homebrew yeast for a very dry beer. Also I have used it with a range of 56 degrees all the way to 90. At 90 it throws lots of esters but the off flavors are mostly fruit, specifically mango and tropical. What you want for an IPA. At 56 its very clean and ferments very quickly unlike a lager strain. I would make sure its a big pitch though if choosing to us it at that temp. I love it. It is my new house strain. I'm guessing since its a wild strain is why its is more tolerant. Plus that flavor from going hot is awesome. The perfect IPA yeast in my opinion.

Jason Stockdale
Brewing since 1999
Joplin Homebrew Club
 
Top