Anyone have experience with Imperial G03?

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rtstrider

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I will be brewing a Kolsch on Saturday and have secured Imperial G03. Has anyone used this before and if so what ferment temps did you use? What temps would you recommend? Low (60), middle of the range (64ish), or upper end (67-68)? I'm leaning more towards 60f and a heavy pitch (2 liter starter). Here's the recipe I'll be using

Brew Method: All Grain
Style Name: Kölsch
Boil Time: 60 min
Batch Size: 5.5 gallons (fermentor volume)
Boil Size: 6.75 gallons
Boil Gravity: 1.040
Efficiency: 70% (brew house)

Hop Utilization Multiplier: 1

STATS:
Original Gravity: 1.049
Final Gravity: 1.011
ABV (standard): 4.91%
IBU (tinseth): 22.32
SRM (morey): 3.57
Mash pH: 5.74

FERMENTABLES:
9.25 lb - Pale 2-Row (90.2%)
1 lb - Wheat Malt (9.8%)

HOPS:
0.3 oz - Magnum, Type: Pellet, AA: 15, Use: First Wort, IBU: 18.79
0.5 oz - Hallertau Mittelfruh, Type: Pellet, AA: 3.75, Use: Boil for 15 min, IBU: 3.53

MASH GUIDELINES:
1) Strike, Temp: 147 F, Time: 90 min, Amount: 3.84 gal
2) Fly Sparge, Temp: 170 F, Amount: 4.84 gal
Starting Mash Thickness: 1.5 qt/lb

YEAST:
Imperial Yeast - G03 Dieter
Starter: Yes
Form: Liquid
Attenuation (avg): 75%
Flocculation: Medium
Optimum Temp: 60 - 69 F
Fermentation Temp: 63 F
Pitch Rate: 1.0 (M cells / ml / deg P)

PRIMING:
Method: co2
CO2 Level: 2.58 Volumes

TARGET WATER PROFILE:
Profile Name: Pilsen (Light Lager)
Ca2: 7
Mg2: 3
Na: 2
Cl: 5
SO4: 5
HCO3: 25
Water Notes:
1 Gram Epsom Salt
1 Gram Calcium Chloride
1 Gram Baking Soda

7.56 ml Lactic Acid

5.2 ph -87.8 ra
 

Conehead

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I made a Kolsch using Dieter yeast last Tuesday. Pitched my starter on Wed morning at 61F. It seems to be slowing down today, ( Saturday ). Now that was quick. I will let it rise to 65F tonight to finish and hopefully I don't have a stuck fermentation. I didn't check the gravity yet, brewing again today.
 

couchsending

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It’s their version of wlp029 which is a slightly warmer fermenting strain than most Kolsch yeasts.

Theres a great article in Craft Beer and Brewing on Kolsch with Matthew Steinberg from Exhibit A. They make a phenomenal Kolsch. He goest through the whole process and theres a lot of info on the cellaring practices for this beer. They use 029. Highly recommend the article.
 
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I pitched this yeast around 1230pm yesterday and by 430pm it was going good! Had a 2 liter starter (started about 18 hours before) and poured the whole slurry in there since I didn’t have time to cold crash. It worked out though because I got high efficiency so the 2 liters of starter knocked this back down to 1.049 lol I ran the calculator and this will end up being right over 20 ibus so only a 2 ibu difference. However...I do not have a lot of head space in the fermenter and the blowoff hose/hung blew out overnight. Finally had my first fermenter blowout! Anywho I’m not too worried about it because the ferment was and is still going strong. Should be fine :) This is fermenting at 60f
 

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Do I need to raise the temp to 65 F at all? It never fermented any quicker with the temp change. The gravity on day 5 was 1.010 from 1.044. It is still bubbling away, but only every minute or a little longer.
 

couchsending

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I would personally... helps with the final bit of attenuation and ensures better cleanup of any remaining acetaldehyde or diacetyl. All esters have already been formed raising the temp can do nothing but help with ale yeasts.

Again that article in CB&B on brewing Kolsch with Exhibit A goes over every little detail and there’s tons of info on their ferm profile and cellaring techniques that all contribute to the final beer. It’s definitely the most in depth info on wlp029 (and Dieter) that you’ll find anywhere. When someone’s brewed the same highly regarded beer hundreds and hundreds of times and is willing to share a lot of very in depth info I tend to listen.
 
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It's right under 72 hours and fermentation is starting to slow down. I'm going to wait till tonight to raise the temp from 60F to 68F for a d-rest/cleanup/etc and leave it there for a few days.
 

Conehead

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I would personally... helps with the final bit of attenuation and ensures better cleanup of any remaining acetaldehyde or diacetyl. All esters have already been formed raising the temp can do nothing but help with ale yeasts.

Again that article in CB&B on brewing Kolsch with Exhibit A goes over every little detail and there’s tons of info on their ferm profile and cellaring techniques that all contribute to the final beer. It’s definitely the most in depth info on wlp029 (and Dieter) that you’ll find anywhere. When someone’s brewed the same highly regarded beer hundreds and hundreds of times and is willing to share a lot of very in depth info I tend to listen.
I got it, thanks for that.
 
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The primary fermentation is almost done. The yeast has a tartness to it. Not like a sour and this was expected as it tastes just like it did straight from the yeast pack. I'm pretty sure that's the "white wine" flavor that is mentioned when Kolsch is brought up. Yeah I tasted the leftover bit that didn't make it in the starter. This lines up with the confirmed try of a wlp029 Kolsch at a microbrewery. Does the tartness age out or fall into a background flavor so it's not so in your face? If so is it better to let it sit in primary for a tad longer before lagering or would lagering clean that up a bit faster? I would like to try the G02 strain with this grain bill as I think it would probably be a better fit for what I'm looking for taste wise. Either way I'm in love with the grain/hop bill. Just have to find the right yeast to pair with it.
 

couchsending

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The White Whine flavor doesn’t really come from 029, that’s more of a 2565 derived flavor.

You’re tasting the starter wort? Or the beer that’s done fermenting? Starter worts are never a really indication of what temp controlled fermentation will be like with the correct pitch rate.
 
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The White Whine flavor doesn’t really come from 029, that’s more of a 2565 derived flavor.

You’re tasting the starter wort? Or the beer that’s done fermenting? Starter worts are never a really indication of what temp controlled fermentation will be like with the correct pitch rate.
I tasted the yeast from the yeast pack. Well what was left after I dumped it into the starter. Wasn't much but it had that tartness to it. Then again this is the same exact tartness I tasted on a wlp029 kolsch at a microbrewery. Actually asked what yeast they used. Tastes identical and doesn't taste like infection at all. I overpitched by a good bit and fermented LOW! I'm going to give it a few more days at warmer temps to see if it cleans up. If anything it's possible it's just the yeast needing to clean up. Not worrying though...If anything lagering might clean it up also.
 

couchsending

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I tasted the yeast from the yeast pack. Well what was left after I dumped it into the starter. Wasn't much but it had that tartness to it. Then again this is the same exact tartness I tasted on a wlp029 kolsch at a microbrewery. Actually asked what yeast they used. Tastes identical and doesn't taste like infection at all. I overpitched by a good bit and fermented LOW! I'm going to give it a few more days at warmer temps to see if it cleans up. If anything it's possible it's just the yeast needing to clean up. Not worrying though...If anything lagering might clean it up also.
Do you take pH measurements when you check gravity? A lot of yeasts will drop pH pretty significantly which can lead to a “tartness” of sorts.
 
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rtstrider

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Do you take pH measurements when you check gravity? A lot of yeasts will drop pH pretty significantly which can lead to a “tartness” of sorts.
Not usually but I can if you'd like! I have a meter but never use it...I know I know....DOH! lol Anywho it's still bubbling away every 23 seconds or so and the krausen is still there. Very good chance this will ferment out I think
 

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I tasted the yeast from the yeast pack. Well what was left after I dumped it into the starter. Wasn't much but it had that tartness to it. Then again this is the same exact tartness I tasted on a wlp029 kolsch at a microbrewery. Actually asked what yeast they used. Tastes identical and doesn't taste like infection at all. I overpitched by a good bit and fermented LOW! I'm going to give it a few more days at warmer temps to see if it cleans up. If anything it's possible it's just the yeast needing to clean up. Not worrying though...If anything lagering might clean it up also.
Tasting plain yeast doesn't have any bearing on what the finished product will taste like.
 
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Tasting plain yeast doesn't have any bearing on what the finished product will taste like.
I'd beg to differ actually. I'll taste the yeast and then what's left over in the flask after the yeast is dumped into the wort. A few head brewers and myself have been chasing down a particular yeast strain. Long story short it's for a very popular NEIPA in our region. Naturally the brewery is tight lipped on what they use so we've cultured that up from bottles and that's helped point us in the right direction. Yes you're not going to taste the hops and grains...Of course! But just like any other ingredient in a recipe it will at least give you an idea of what you're working with ;)

Edit: Now rehydrated dry yeast is a whole different ball game from my experience. Yeah that has no bearing on anything. I'm only speaking of liquid yeast and starters
 
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Update

Just pulled a sample of the kolsch and the tart has faded big time. It’s more rounded now and looks to be about done with primary fermentation. Now it has a white wine twang to it, in the background, which is very nice! Going to start cold crashing this in the next few days. So far this has a faint fruit note on the nose with white wine in the background.
 

Twinkeelfool

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I love 029, I use it very often but I never get any kolsh like flavours with it. I normally ferment around 15c/60f and I find it super clean.

Do you need to do anything to promote the white wine flavours?I use 2565 when brewing kolsh
 
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Update:

The beer was CLEAN and clear going into the bottles. I cold crashed and added gelatin prior to bottling. It'll be 3 weeks of bottle priming on Friday. I tested a bottle last night and it's carb'd. The only thing that's changed is that it's very yeasty. No off flavors per se but it has the same yeast bite it did when I first sampled it in the hydrometer tube. This will need to lager for a bit to smooth back out for sure. I'll say this though. After talking with the wife I'm going to have a 2 keg setup for lager/kolsch's early next year. If I carb'd up what was transferred to the bottles...Man that was absolutely delicious! Now I have to lager all over again. It's just not worth it imo I can get the benefits of a long term lager using gelatin and 1 week of cold storage so that's the selling point here.

Back to the yeast. The characteristics of this yeast is that it's tart/sour and bitter. Now if you can lager it or hit it with gelatin and let that sit for a week or so...It's nice! Once it drops it leaves a slight fruity undertone which I'd describe as banana. I mean it's ever so slight and it drops clear easy with gelatin. I'm a huge fan and will use this yeast again for sure!
 
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rtstrider

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Well the kolsch has cold conditioned and it’s clean! I mean clean as clean gets. No more esters or yeast derived anything lol I’ll go as far as to say it’s so clean it’s almost too bland. I could see where this would work extremely well in a pseudo lager/cream ale fermented at 60f. This drops clear in no time with gelatin! Anywho the attached pic is after 2 weeks in the fridge. It’s extremely crisp!
 

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Well the last bit of this was tapped out over the weekend. This yeast is one of my favorites! I experimented and built up some slurry from the bottles and just put them in a water/glycerin mixture in test tubes. Going to freeze them. Ended up getting a keg setup and it should be up and running by this weekend. This kolsch is going to be brewed again as is and go straight to the kegerator. It was just way too good! It had some character in the bottles that was not there prior to bottling. Extra yeast character that is. I'm really curious to see if this stays crisp and cleaner in a keg vs the bottle.
 

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