Dunkelweizen pitch rate and temp experiment

Ingredients
1

After Reading Denny’s open letter on experiments and recently taking up small batches I have decided to put my small batches to good use. I plan on doing 4 small batches of Dunkelweizen. Two batches at one temp and two at another. Each temp will have different pitch rates so I can fine tune the recipe to exactly what I want and learn something in the process. That being said I thought I would get suggestions on pitching rates and temps (include your reasoning as well). The plan is to ferment two batches at temp X and two batches at temp Y. Each temp has a batch with a high pitch rate and one with low pitch rate, or a maybe a mid and extremely low pith rate ect. NOTE The pitch rates will remain constant at both temps. The recipe (less scaling) is below. The OG is a little high per style so I will be upping the hops slightly for better balance. Weihenstephan 3068 is What I have used both times and is available fresh at the LHBS. I will be buying a fresh smack pack for each brew day and measuring yeast as accurately as I am capable. batches will be no bigger than 1.5 gallons each. So brew day total will yield no more then 3 gallons into fermenters. Naturally, I will share results when its through. If you live in driving distance of Everett WA and want to take part in the four bottle evaluation shoot me a PM. Im expecting all beers to be ready around Christmas, maybe earlier.

Dunkelweizen BASE LINE

Dunkelweizen (15 B)

Type: Extract
Batch Size: 5.25 gal
Boil Size: 3.78 gal
Boil Time: 60 min
End of Boil Vol: 3.64 gal
Final Bottling Vol: 5.00 gal
Fermentation: Ale, Two Stage

Date: 17 Mar 2015
Brewer: Jonathan W.
Asst Brewer:
Equipment: 5 Stove top/8 gal pot
Efficiency: 72.00 %
Est Mash Efficiency: 0.0 %
Taste Rating: 30.0

Taste Notes: brewed this once before with brewtarget and was over hopped by 25 percent(oops). that brew was great and was spicy/clove heavy. fermentaition temps were not recorded. OG for that batch was close.
made with DME extract the second time around. the beer was very close despite using correct hops and unkown fermentaion temps.(no chamber at time)

Ingredients

6.0 oz Caramel/Crystal Malt - 40L (40.0 SRM) Grain 1 3.8 %
6.0 oz Special B Malt (180.0 SRM) Grain 2 3.8 %
2.0 oz Carafa II (412.0 SRM) Grain 3 1.3 %
3 lbs 12.8 oz Wheat Liquid Extract (8.0 SRM) Extract 4 38.5 %
2 lbs 3.2 oz Pale Liquid Extract (8.0 SRM) Extract 5 22.3 %
1.00 oz Hallertau [4.00 %] - Boil 60.0 min Hop 6 12.5 IBUs
1.0 pkg Weihenstephan Weizen (Wyeast Labs #3068) [124.21 ml] Yeast 7 -
3 lbs Wheat Liquid Extract (8.0 SRM) Extract 8 30.4 %

Gravity, Alcohol Content and Color

Est Original Gravity: 1.059 SG
Est Final Gravity: 1.015 SG
Estimated Alcohol by Vol: 5.9 %
Bitterness: 12.5 IBUs
Est Color: 17.9 SRM

Measured Original Gravity: 1.060 SG
Measured Final Gravity: 1.014 SG
Actual Alcohol by Vol: 6.1 %
Calories: 201.6 kcal/12oz

Volumes of CO2: 4.5
Carbonation Used: Keg with 38.02 PSI
Age for: 30.00 days
Storage Temperature: 65.0 F

2

Good on ya!

3

Here is what Wyeast has to say about the strain

“The classic and most popular German wheat beer strain used worldwide. This yeast strain produces a beautiful and delicate balance of banana esters and clove phenolics. The balance can be manipulated towards ester production through increasing the fermentation temperature, increasing the wort density, and decreasing the pitch rate. Over pitching can result in a near complete loss of banana character. Decreasing the ester level will allow a higher clove character to be perceived. Sulfur is commonly produced, but will dissipate with conditioning. This strain is very powdery and will remain in suspension for an extended amount of time following attenuation. This is true top cropping yeast and requires fermenter headspace of 33%. Attenuation: 73-77% Temperature Range: 64-75° F (18-24° C) Alcohol Tolerance: approximately 10% ABV”

So let’s break out the important stuff,
variables:

High temp = increased ester production

Hi gravity= increased ester production

Low pitch = increased ester production

Over pitching= little to no banana/esters

Effects:

Decreasing esters = more clove perceived

Given the above, I would believe the following to be true or at least plausible:
variables:

Low temp= reduced ester production

Low gravity= reduced ester production

Standard pitch= balanced ester production.

Effects:

Increasing esters= less clove perceived

The OG for this recipe is a little the high side but is where I want it so gravity is not variable. So that leaves the following to consider

Low temp= reduced ester production

High temp = increased ester production

Low pich = increased ester production
Standard pitch=balanced ester production

Over pitching= little to no banana/esters

The first Dunkelweizen I made was clove heavy and I loved it and want to explore that end of the spectrum, so 2 batches will be fermented at the low end of the range to reduce esters and will have pitch rates that favor reduced banana/esters.

Here is the plan so far.

Round 1

Temp: Low(exact temp undetermined)

Batch 1 Pitch rate: over pitched (exact Pitch rate undetermined)

Batch 2 Pitch rate: standard pitch (exact Pitch rate undetermined)

Round 2

Temp: undetermined

Batch 3 Pitch rate: undetermined

Batch 4 Pitch rate: undetermined

Not yet sure what source I’m going to use as a reference for pitching standards. I’m considering the Calculator provided by Wyeast or the guidelines in Palmer’s How to Brew but open to suggestions.

4

So I am by nooooo means an authority, or even claiming to be experienced.  Dunkelweizen was my FIRST home brew.  I had a really wonderful yeast ester banana aroma and creamy banana mouth feel and that warm/wet banana bread taste/sensation out of WLP351 Bavarian Wheat.  My fermentation temps were as thus:
72F  for 20 hours
66F-67F for 7 days
Now it has balanced ate up its sugars and brought OG from 1.058 to 1.007 (87% Att) now 2 days in a row.  So I am assuming the beer to be finish.  I don’t know what temps you are playing with, or considering, but this ester and phenolic flavor IS VERY similar to Ayinger Ur-Weisse [ Dunkelweizen ] and that is what I had made my mark.  Let me know what you think?  Also what temps you tried and what you think turned out the best.  As this being my first experiment ever, I obviously do not have a lot to offer, but hey, so far (prior to drinking my beer cold and carbonated) I am happy with what I got.

5
6

After much delay looks like I’m brewing this weekend.

Round 1

Temp: 65

Batch 1 Pitch rate: over pitched (exact Pitch rate undetermined)

Batch 2 Pitch rate: standard pitch (exact Pitch rate undetermined)

Round 2

Temp: 70

Batch 3 Pitch rate: over pitched (same rate as round 1)

Batch 4 Pitch rate: standard pitch (same rate as round 1)

I’m still not sure what source I’m going to use as a reference for pitching standards though given the speed at which the weekend is approaching I guess I will know soon.

7

Nice!! How do you plan to evaluate them/have them evaluated? Super interested!

8

Nothing set in stone. I will have my wife administer/conduct/proctor a blind tasting for my self and I will probably seek out a group of 3 or more qualified tasters. I thought I could use friends at first but on second thought my friends locally are not quite qualified to give the kind of feedback that I am looking for so I will probably find some discerning palates through my local homebrew shop, or mail some off or see if anyone on the forum lives near Seattle or something… I would like to join a club but all of the clubs meet when I’m at work so until I’m on first shirt I may be on my own which is unfortunate because all I want to do is talk beer, brew beer, drink beer, repeat.

9

Sounds rad. Keep your tasters blind to the nature of the experiment!

10

Round 1 has been brewed and is in the ferm chamber with the higher pitch rate air lock bubbling away while the lower rate airlock remains motionless for the time being.

Bucket 1 Pitch rate:
.65 Mil cells (fresh)/mL/deg Plato
(42.5 Bil cells into 1.11 gal @ 1.063)
Ferm temp: 65

Bucket 2 Pitch rate:
.30 Mil cells (fresh)/mL/deg Plato
(19.5 Bil cells into 1.11 gal @ 1.063)
Ferm temp: 65

The higher rate is based on one week old smack pack going into a shaken not stirred starter @ 1.040 (yield based on Chris White numbers/calculator) and then into 5.25 gallons @ 1.063

The lower rate is based (roughly) on a one week old smack pack going directly into 5.25 gallons @ 1.063

Measuring cells to .5 with great accuracy is not something I had really thought about much before brew day but I did my best and probably came pretty close. Cell density was .736 Bil/mL in the pack I had. (based on viability) In the future I will probably add some wort to bring the density down to .5 Bil/mL or lower to make measurements more accurate. All in all I feel pretty good about how things went and my ability to create (near) identical batches for the second temp.