The definitive hefe yeast thread - fermentation profiles and flavor results

I have been perfecting and tweaking my Weiss for the last year. And although I have a great Weiss, it is missing something. I have been soley using wlp300/wyeast 3068 in my recipe, and I've tried many different fermentations but can't seem to get that clove punch that I want! I've also been battling sulfur that tastes like shrimpy pond water. What I've learned is that too much protein rest= excessive sulphur formation & yes, thinner beer. I have been using acid malt, and I think that my final product is a little too acidic, as I can't seem to get that round, slightly sweet wheat mouthfeel that the commercial examples have. Mine has too much citrus tone to it with the acid. What I think I will be doing, is brewing up a 2 1/2 gal batch, and splitting into 4 glass cookie jars. (I use these for yeast propagation, since I can't seem to keep an erylenmeyer flask intact for more than a week!) Into each container I will pitch 38 billion cells of 4 different yeasts. (pitch rate of 16 mil per ml) Will ferment starting at 60 and raising to 64 with swamp cooler and fish tank heater, and finishing out at 68. Since it will be easier to measure out 1/3 of a vial than a smack pack I'll be testing out WLP 300, WLP 351, WLP 380 and cultured kellerweiss.

I understand that there are many variables in producing the flavors I desire, my hope is that this thread will help myself and other brewers zero in on the factors that will help them get what they want from their yeast. For the purposes of this thread, I would like anyone who has experience with hefe yeasts to list their results. Please include yeast brand, mash rests used with times, OG, pitch rate (how much yeast/batch size), pitching temp, aeration info, fermentation temp profile, vessel info (open or closed), finishing info, flavor notes. Include how the ester/phenol changed with time.

I'll start:
Brew date: 12/29/11
Yeast: Wyeast 3068
Mash profile: 113* for 15 min, 122* for 15 min, 128* for 15 min, double decoction for sacc rests, 75 min boil
OG: 1.047
Pitch rate: 1 L starter into 5.5 gal
FV: plastic bucket, closed with 3 piece airlock
Pitching temp: 67*
Aeration: 48 sec O2 through 2 micron stone
Fermentation profile: put fermenter into swamp cooler after pitching, it dropped to 54* by the next morning. Switched out warm water to bring temp up, settled around 60-61* for main part of fermentation. Brought upstairs and it got to 64* to help decrease the sulphur.
Finishing: kegged and purged with CO2 to reduce sulphur. On tap at 3.0 volumes.
Flavor: huge sulphur! After yeast settled and conditioned sulphur subsided. Banana and clove subdued, but balanced. Slight citrus twang.

Please do not post theoretical information that you have not backed up with actual results. I'm hoping we can prove/disprove the "common" hefe advice. We all know it, but it may not be as simple as ferment warm for banana, ferment cold for cloves. What I've been researching/ reading lately is that you under pitch to accent banana (6 mil/ml), pitch adequately (12 mil/ml) for balance and over pitch (14-18 mil/ml) for cloves, then use temperature to control intensity. Warmer = more flavor compounds, but higher risk of off flavors, and colder = subdued and cleaner ferment, while still having the esters and phenols that the pitch rate would determine.

I will post more as I look through my notes and as my experiments progress.

The ferulic acid rest is supposed to promote cloves. Also, 62 is the recommended fermentation everywhere I have read (admittedly only Brewing With Wheat and Brewing Classic Styles).

afr0byte said:

The ferulic acid rest is supposed to promote cloves. Also, 62 is the recommended fermentation everywhere I have read (admittedly only Brewing With Wheat and Brewing Classic Styles).

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Yes, have been reading that as well, but I would like everyone to share their results. Other factors in production of 4-vinyl guaiacol are percent wheat which with a hefe will be 50-70%, fermenter shape and headspace pressure, oxygenation rate, and pitch rate. Mess anyone of those up and you may not get quite the ester/phenol profile you want.

Trust me, I'm not Bill Nye the Science guy, my mash schedule was given to me by a good brewing friend with far more experience but my Hefe turned out great!

6.25G batch
WY3068

All German Hefe, 50% German wheat malt, 50% German Pils. 2 oz total Hallertauer hops, 1oz FwH, .25 @20, .25@10, .25@5, .25@FO

Whirlpool, gravity drain through CFC into primary at 61F, pitched +\- 300B cells (3 step starter)

Mash, 122F for 30 minutes, raise to 158 for 30 minutes, raise to 168 for 10 , batch sparge 1 step @192F

Ferment at 58F for 21 days, bottle with 5.2oz priming sugar, condition 14 days.

Pleasant banana aroma, malt forward, nice dense head with average retention, good lacing, strong clove flavor with slight banana tones throughout.

Proven very popular, need to brew more.

Brew date: 2/5/12
Yeast: Wyeast 3068
Mash profile: single infusion @154* for 60 min. 65 min boil
OG: 1.051
Pitch rate: 1 Smackpack into 5.5 gal
FV: plastic bucket, closed with 3 piece airlock
Pitching temp: 66*
Aeration: 60 sec O2 through 2 micron stone
Fermentation profile: put fermenter into swamp cooler after pitching, it dropped to 62*, aroma phenolic. Turned on fish tank heater and brought up to 63* by next morning, that evening huge egg farts. Up to 65* by morning 2. Up to 66 morning 3, smell turning to green banana smell, and sulphur diminishing. @ 2 weeks aroma had changed over to ripe banana. Fermentation stayed at 66-67* for peak. Raised temp to 68 to finish it out.
Finishing: kegged & on tap at 3.0 volumes. Only kegged 4.75 gal, was careful to leave any trub and a layer of thick/hazy beer behind.
Flavor: First pulls were very chunky and yeasty. Sample the other night, 18 days after kegging: Holy banana bread! Dense head that tastes like sweet banana bread batter. Definitely too sweet, this could be from carapils addition, cutting my acid malt, or cutting out all acid & protein rests to decrease precursors to the sulphur compounds. Will see how this ages. Clove very faint. Banana dominates.

Edit (5/4/12): tasted again at Easter. Has lost that very sweet flavor that I got after first kegging, I now suspect that to be from the larger proteins that had settled out in my keezer. Subsequent pulls have been very similar to my past results. Slight sour/citrus, subdued balance of clove to banana, banana dominates the aroma, and sulphur that lingers. Definitely better and cleaner than the 12/29/11 batch that I reviewed at the start of the thread... But still not where I want it to be.

mcbethenstein said:

Brew date: 2/5/12
Yeast: Wyeast 3068
Mash profile: single infusion @154* for 60 min. 65 min boil
OG: 1.051
Pitch rate: 1 Smackpack into 5.5 gal
FV: plastic bucket, closed with 3 piece airlock
Pitching temp: 66*
Aeration: 60 sec O2 through 2 micron stone
Fermentation profile: put fermenter into swamp cooler after pitching, it dropped to 62*, aroma phenolic. Turned on fish tank heater and brought up to 63* by next morning, that evening huge egg farts. Up to 65* by morning 2. Up to 66 morning 3, smell turning to green banana smell, and sulphur diminishing. @ 2 weeks aroma had changed over to ripe banana. Fermentation stayed at 66-67* for peak. Raised temp to 68 to finish it out.
Finishing: kegged & on tap at 3.0 volumes. Only kegged 4.75 gal, was careful to leave any trub and a layer of thick/hazy beer behind.
Flavor: First pulls were very chunky and yeasty. Sample the other night, 18 days after kegging: Holy banana bread! Dense head that tastes like sweet banana bread batter. Definitely too sweet, this could be from carapils addition, cutting my acid malt, or cutting out all acid & protein rests to decrease precursors to the sulphur compounds. Will see how this ages. Clove very faint. Banana dominates.

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If you're actually only pitching 1 smack pack for a 5 gallon batch that is probably the reason for your excess sulphur. You're pitching roughly 1/2 (assuming a very fresh pack) of the recommended amount of yeast.

EDIT: Also, if you're pitching cold then the proper pitching rate is even more important.

This is my standard hefe profile:

60% Wyermann Wheat malt
40% Pilsner (usually Best Malz)
OG: 1.053
FG: 1.012

1oz Hallertau @ 90min (~10IBU)

Single Infusion Mash @ 156*F. I know this is unusual for the "perfect hefe," and I could probably have some sort of impovement using a step mash, but at the moment I'm good with my results.

White Labs WLP380 Hefe IV
I like this yeast much more than the WLP300/3068 strain. Over-the-top banana is a huge turn-off for me with a lot of homebrew hefes, and finding a more balanced strain was key. This is comparatively clean for a hefe yeast, but still gives some nice clove notes.

Aerate with pure O2 for 60 seconds.
Pitch at the standard Mr Malty rate.
Ferment @ 65*F

This gives me a hefe that is right down the middle in almost every aspect. Medium-light body, moderate clove/banana, some bready character, and super easy drinking.

I haven't tried it yet, but WPL380hefeIV is supposed to be more "clovey" I have a tube in the fridge for the next batch

Here they are. Getting ready to chill the wort. I hope this comes out well. I would really like to know what yeast I like!

Edit: update 4/2: pitched at 5 pm yesterday pitching temp was 62*. It was hard to pour out 1/2 a tube... I adjusted for viability based on manufacture dates. The WLP 380 was 2 1/2 months old, so I pitched the whole tube.

Checked on them this morning. All smell pleasantly phenolic, with 380 being the strongest. WLP 300 is the most subdued, could smell some eaters in there too. The 351 and kellerweis have the biggest start on their krausen; fluffy, white and about 3/4 in high already.

Pic of the four test batches. Swamp cooler temp is at 59*. Infrared measures at 59.9-60.2 in all fermenters... Except WLP 300, that's about .5 degree higher.

The covers are all very loose. Screwed on with only 1 thread. That makes this a modified open fermentation.

What size are the batches?

About 3/4 gal each. Smaller than some starters I've made. But I adjusted my pitch rate to match.

Hmm, I'm assuming all of the yeast must have been a bit old? A half tube seems like quite a bit for a 3/4 gallon batch.

Great experiment, mcbethenstein. Excited for your results.

afr0byte said:

Hmm, I'm assuming all of the yeast must have been a bit old? A half tube seems like quite a bit for a 3/4 gallon batch.

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Yes, but I am pitching at 18 mil/mL the rate indicated to maximize clove. I adjusted for productions dates... But was not as scientific as I hoped in pouring the tubes out. My main goal with this test is to select a strain to work with from here on out. After that I'll run more testing with pitch rates and fermentation temps.

I'm fermenting out my first HW as we speak, so I hope it's okay if I ask a follow-up question here. Will I have sulfur flavor if I smell it coming from the airlock? I was under the impression that some of this was normal and that I wouldn't taste it in the finished beer (or that it would condition out).

Also, there's a note above about the sulfur being caused by under-pitching. Is this the only cause? My pitch rate should have been right on.

Thx for starting a thread on this topic.

krahm said:

I'm fermenting out my first HW as we speak, so I hope it's okay if I ask a follow-up question here. Will I have sulfur flavor if I smell it coming from the airlock? I was under the impression that some of this was normal and that I wouldn't taste it in the finished beer (or that it would condition out).

Also, there's a note above about the sulfur being caused by under-pitching. Is this the only cause? My pitch rate should have been right on.

Thx for starting a thread on this topic.

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Some hefe yeasts apparently naturally/normally produce sulfur. However, if they're anything like lager yeasts, lower pitching rates will tend to increase the sulfur production. I've never actually brewed a hefeweizen (I have brewed a dunkelweizen.), but I'd guess that if you can smell the sulfur coming out of your beer, then that sulfur isn't going to be in your beer. Also, if they're anything like lagers, the remaining sulfur will leave the beer eventually.

afr0byte said:

Some hefe yeasts apparently naturally/normally produce sulfur. However, if they're anything like lager yeasts, lower pitching rates will tend to increase the sulfur production. I've never actually brewed a hefeweizen (I have brewed a dunkelweizen.), but I'd guess that if you can smell the sulfur coming out of your beer, then that sulfur isn't going to be in your beer. Also, if they're anything like lagers, the remaining sulfur will leave the beer eventually.

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What he says appears to be correct from my experience. Let your beer sit on the yeast until you no longer smell sulphur coming from the airlock. If there is any left usually it will fade in the bottle. Good luck! I hope many others will post their results, so we can get it all in one thread, the more detailed the better. Let us know what happens with yours.

Morning update: all fermenters at 61.3 degrees, except that hot head WLP 300. It's at 61.7. Krausens have compacted a bit. Aroma in each has a hint of sulphur, but it is much milder than any other hefe ferment so far. Yea for over pitching!
At this point I decided against trying to raise the temp with the fish tank heater as there is no space for it to go to equally effect each mini fermenter. I'll let it ride at 61-62 degrees.

Tasting notes: I bottled with 1 1/2 coopers tabs in 16 oz. ayinger bottles after a 5 day cold crash. They are approximately 2 weeks old.
WLP 300: aroma - pleasant banana aroma. Taste - clove, sulphur, slight sour, very little banana. This is the same as the others that I've brewed. The clove is definitely more present with this pitch rate, but the sulphur lingers as well. A good yeast, but not what we are looking for.
WLP 380: aroma - spicy, wheaty, clean and very pleasant. Taste - very clove/ spicy phenolic forward. Hint of sour, but not very evident...( I do use acid malt, so this is likely from the grain bill, whereas the 300 sour is more prominent.) No banana, very slight hint of flavor reminiscent of apricot. Minuscule amount of sulphur, right at the detection threshold. Some sips seemed free of sulphur, and some you could just pick it up.

Having not sampled the other 2 yet, I rank 380 as better than 300 for the flavor profile we are looking for. I am very excited to try the 351 and kellerweis tonight. I did make a dunkelweiss with the kellerweis strain and it turned out very well. It was voted the favorite at our club meeting last week. I'll update later with the other tasting notes.

We tried the other 2 from round 1 last night. When I bottled I was able to get 4 of each. My intention is to try them each week, with the last 4 being shared with a small group of hefe lovers at our club meeting.

WLP 351: poured out with very little head, and seems a bit under carbed. Tried to swirl yeast in, but ended up with large yeast chunks in suspension of an otherwise clear beer.
Aroma - STINKY! Can only assume this is a sulfide derivative because it smells exactly like perm solution. The aroma lingered and greatly affected the taste perception.
Taste - clove/phenolic, but in a intangibly different way than any other clove taste. Can taste the "perm" solution sulphur, almost lagerish in taste.

Kellerweis: poured a thick head, yeast swirled nicely into solution. Beautiful in glass. a little light on carbonation yet as well, but not flat.
Aroma - clean and pleasant, nothing sticks out but this is the nicest smelling of the four.
Flavor - cloves, sweet malt, wheaty, slight banana, ever so slight sulphur, lacks the tart/sour that would balance the sweet malt. This was drank the fastest out of the 4.

Rankings after round 1: could be a tie for first, but the edge goes to kellerweis, then 380, 300, and 351 last. We'll see how they rank after the next round. But I can tell already that it will be 380 or kellerweis as my house hefe yeast from here on out.

Interesting. Two aspects of the White Labs description of 380 would keep me from trying it, though: that it is "phenolic" and that "sulphur production is higher."

But maybe I should try it on a smaller batch, like you're doing, to see whether these are acceptable to my palate.... Or even preferable.

All of them will and did produce sulphur, but with the 380 it seems to have bottle conditioned out very well. Same with the kellerweis. Give it a try. Based on the descriptions on white labs page, I was expecting to like the 351 the most, but it came out so much differently than I thought.

Round 2 of tasting went like this:
300 - very similar to last tasting, banana hints even more subdued than the last round. Taste is much more complex, and cohesive. Very pleasant.
351 - funky smell almost completely gone. Flavor is mostly that different clovey phenolic, with a very forward citric acid bite. 180 degrees different than the first taste.
380 - almost exactly the same as the first tasting, very pleasant, mild stone fruit with heavy cloves. Justin still detects a very tiny bit of sulphur, I don't.
KW - very similar to last time as well, pleasant, the almost sweet taste is gone, and an ever so slight tartness is present. Still very pleasant.
Rankings:
From me: 1- 380, 2 tie KW & 300, 4- 351
From Justin: 1- 351, 2- 380, 3-KW, 4-300... Justin really liked the acid bite that the 351 developed.

I will report more in the next few days. I am taking the remaining 8 bottles (2 of each) to our club meeting tonight. I will collect people's impressions of the beers and their rankings as well.

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I take it that, as brewed, the Kellerweis and 380 beat out 3068 in terms of cloves? I'm about to brew my weizens for the year and I really like your documentation of your experiments. I may have to culture up some KW or look out for the Wisconsite strain coming soon from Lakefront and Jeremy King of Northern Brewer.

How do you think these strains behave in the keg, any different from being bottle-conditioned?

14thstreet said:

I take it that, as brewed, the Kellerweis and 380 beat out 3068 in terms of cloves? I'm about to brew my weizens for the year and I really like your documentation of your experiments. I may have to culture up some KW or look out for the Wisconsite strain coming soon from Lakefront and Jeremy King of Northern Brewer.

How do you think these strains behave in the keg, any different from being bottle-conditioned?

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I see you are a beer baron... Were you at the meeting last night? I was having a few people do samples and reviews... I'm always in the middle table along the back wall. I will be writing up my summary of the experiment for the next baron mind, but it will all be updated on here sooner. I have several baby food jars of yeast recovered from the experiment, I could give you one from the kellerweis if you want to meet up. I think the strain from Jeremy is already available.... He calls it Jazz Hands...Jeremy.....lol. I had a sample of the Wisconsinite when i bought the yeast for this experiment, Jeremy let me taste one of their test batches, before it ran into production... It's good.

And to answer your first question, yes, the 380 won out for cloves. I'll post more later, I'm gathering the reviews I got last night together to post my final results.

I've only kegged the 300/3068 and I didn't notice a significant change from how they bottle condition. Ask me in July about the 380. I'll be brewing up my germanfest batch in the next 2 weeks, so I should know by the July meeting about the keg conditioning for 380...

So.... Last night I took the weizens to our club meeting. I had 12 people review the beers and got rankings back from 10 of those people. As one would expect, the comments varied. However there was a pretty interesting break down, with reviewers falling into 2 main categories. There was the majority (6 reviewers) that fell into the category that preferred the traditional Hefe flavor profile. The results from this group all ranked WLP 380 as #1, Kellerweis as # 2, WLP 300 as #3 and WLP 351 as #4, one person flipped Kellerweis (#3) and WLP 300 (#2) in rank and another flipped WLP 351 (#3) and WLP 300 (#4). The other category that 4 of my tasters fell into was those preferring the tart-sourness above all other flavor characteristics. In that group WLP 351 reigned supreme. 3 of the 4 placed WLP 351 as their top pick and WLP 380 as their least favorite, and the fourth person chose kellerweis as number 1 and WLP 351 as second. The only universal truth that came out of my 10 ranking tasters was that Kellerweis is awesome and averaged a rank of 2 throughout, and was never awarded a 4. Below are some of the comments that were given about the samples:

WLP 300: All banana odor, Taste slightly sour, tart, low banana taste, almost American wheat-ish

WLP 351: Lower odor, touch of cloves with banana, almost funky, 2 reviewers noted the flavors of sour apples and pears

WLP 380: Great smell, great blend of clove/banana, almost banana bread, Balanced, Really F*ing good, Weiss flavor right on, a reviewer that placed it as 4th thought it was overly fruity

Kellerweis: Low odor but balanced, flavors right on but phenolics at a low level, nice tart flavor, fruity, stone fruit.

After this experiment I find myself torn. I am very pleased with the results from both the WLP 380 and the Kellerweis. I would like to continue the process and experiment with both. Since my next batch is for a competition I won't be experimenting much with that one. I will proceed with the 380 as my yeast, and as one of my reviewers (who is also a nationally ranked Judge) suggested I will bump up my fermentation temps to pitch at 62 and ferment at 64-65. After that I will keep this thread updated with my future experiments. I foresee a side by side comparison of primary fermentation temps and maybe a pitch rate test as well, but those will be down the road. Anyone have any thoughts or questions?

Yes, I was at the Baron's meeting but there were too many single-hop beers to try out...never did get to try them all. Anyways, I should try and culture up KW myself before I take some from you, thank you for the offer. Yeast strain probably has the greatest effect on the amount of cloves and I can't say I've gotten a lot with 3068. I was going to enter a hefe (that I haven't brewed) for Germanfest but now may only enter my oktoberfest Best of luck!

14thstreet said:

I was going to enter a hefe (that I haven't brewed) for Germanfest but now may only enter my oktoberfest Best of luck!

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I say you should still enter! If nothing else you can get some good feedback. Plus I welcome some friendly competition!

Thanks for the great post. I have toyed with these strains. The one thing that drives me crazy when people discuss hefe's is the 62 thing. We all read and listen to the same stuff and I know from experience that fermenting with a a 50/50 recipe with WLP 300 at 62 degrees is not going to win you an award every time. Wheat beers can be an enigma. I have scored lower than I anticipated in the category in the past because I took a simple approach. You post is very similar to what I have been working on. I have had much better luck with WLP 380 but it is not always available. I think 64 to 65 is more like it. These strains are a little temperamental. There are a lot of factors to consider. It seems to me that you never really see too many 15a blow away any competitions because well it seems so simple but it is tough to get right.

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Brewed my batch up for Germanfest. I pitched a 3L starter of WLP380. Oxygenated for 90 seconds. Pitched at 70 degrees, then put it in the swamp cooler. It was down to 65 by the next morning, and was back up to 68 degrees by about 18 hours. Added a ice pack and took it down to 66 degrees. Stayed there for the rest of the week. Open fermentation for 25 hours after krausen was present. The first 3 days were very phenolic smelling, then the sulphur came out.

Sample pulled tonight: sulphur in aroma, banana, citrus. Flavor is mainly apricot, a touch citrus and a bit of the sulphur. Clove is strangely absent, or covered up. I turned the fish tank heater up to take the beer to 68 again to clean up. I really am hoping that the sulphur goes away and the clove comes out. It is counterintuitive that there is no clove at all given the pitch rate, oxygenation & and fermentation temps. But even if we can only get rid of the sulphur it should be really nice. I have 2-3 weeks to decide if I'm going to carb naturally in the keg (which may help with the sulphur, but end up with more sediment), or if I'll force carb. Anyone have any experience with 380 and how it ages, especially prior to kegging/bottling?

Question for you folks.

Brewed a Dunkelweizen recipe this weekend. OG finished off at 1.060.

Used one vial of White Labs Hefeweizen yeast and pitched at around 70. I put it in the fridge at 62 for around 12 hours then changed the setting to 68 so that the temp would rise up to around 67 and level off during fermentation.

I checked this morning and there are no signs of active fermentation. I know its still early but just want to see what you guys think about pitching with only one vial of that yeast. I don't have the material to do a starter and the owner of my LHBS said I would be ok with only one vial. Am I in trouble, or should I just wait it out?

Give it time. The lag time when you don't see airlock activity is when the yeast get busy reproducing, and determining your flavor profile. If you are unsure, give it a whiff. I always smell a clovey/phenolic aroma coming from what looks like a non-active fermenter before there is krausen or airlock activity. I'm willing to bet that you will see activity if not by tonight, then by tomorrow am. If no activity and no gravity change after 3 days, then I'd repitch. Since there was no starter it may take a few days for your yeasties to wake up and get in the groove.
As far as flavor and temp go, one vial will turn the odds in favor of you getting more banana out of this than clove... Depending on which strain you chose. But that will be great in a dunkelweiss.

Great, thank you for the info!

Just following up... fermentation took off last night. Everything looks great!

I have an email out to white labs right now to see what their take on pitch rates and fermentation temps are for their hefe yeasts. Today's sample seemed very much like pond water... bringing me back to why I started this thread. Not sure if its from the over pitching at a higher temp, or if it's from changes in my process. I scaled the recipe up keeping the same pitch rate, but I did switch from a BIAB to my regular mashing. I don't think it's contaminated...all my other beers come out clean, but with the mini ferment test I added my speciality malts and acid malt at the sacc temps after the acid rest. When I did this last brew a few weeks ago I ground all the grain together and threw that in for my ferulic acid rest, then up. Maybe I'm over acidifying my mash...maybe that is the cause of this whole thing. I think I've come to the conclusion that I need to brew it again, and wait to add my acid malt until after the ferulic acid rest, and pitch and ferment at lower temps, closer to those of the mini ferment... then see if that solves the issues I'm having again. Thankfully a White Labs rep is coming to NB Milwaukee to talk this friday, so I will ask her what I can do about this if they don't get back to me by then...and then re-brew on Saturday or Sunday...I'll just make it in time for the contest then. Agh! Too much stress! I'm too invested in this right now, I'm going crazy!

mcbethenstein, I haven't read all the posts in this thread, but have you considered that you are over-oxygenating your wort? I've read that this can cause your beer to be very bland and devoid of clove and banana flavors. There is a thread on this site somewhere with a quote from a scientific study that explained this. I can't find it now, but searching hefe oxygenation rate or something close may find it.
I just made a weizenbock with almost no coves and bananas. My pitch rate was the standard ale rate, but I oxygenated for 60 sec at full blast with my aeration stone. I did the same with a standard hefe a few months before and go the same results. Before I got my aeration stone I made a hefe and it had a good balance of clove and banana fermented at 67F. I hope to brew a hefe again soon to test my aeration hypotheses. I'll report back when I do.

I don't have first hand experience with it, but the acid rest may need a few hours to change the pH significantly (see Palmer; http://www.howtobrew.com/section3/chapter14-2.html). Without knowing your mash pH, it's tough to say. I certainly don't want to complicate matters. I have used acid malt before but not enough to clearly understand what it does as far as pH and resulting flavors go (not just the lactic acid but how it plays with the other malts and fermentation). One would think that lower pH brightens up the beer, not dull it out.

slarkin has a point about overoxygenation, and I too can't find what he's talking about. You had a 3L starter and perhaps with very active hefe yeasts you don't need a heavy dose of oxygen. You may have a situation that just muddied the beer up and you get blandness as a result. Is this a repitch or fresh vial?