Aged Schwarzbier-style has cherry soda aftertaste

[leedspointbrew]

I brewed a Schwarzbier-style (italics mine for emphasis; this is not and I didn't expect it to be a true Schwarzbier) that after bottling and aging tastes good, in the sense of not infected, contaminated, stale, green apple, etc. It has a faint aftertaste almost like cherry soda. Which is not necessarily unpleasant, but is certainly not intentional, and I can't figure out what exact step in my process caused it.
This is the recipe / grain bill :

3.25 lbs Pilsner malt
2 lbs Munich malt
5.6 oz Carafa III
5.6 oz Caramunich
4 oz Chocolate
Typical 60 minute infusion mash, recorded temps around 148.

.75 oz Williamette @ 60 min
.75 oz Williamette @ 30 min
.75 tsp rehydrated Irish moss @ 15 min

OYL-071 / Lutra yeast @ 90

I let the beer sit in my Fermzilla at ambient room temps of about 68 degrees for 10 days and then bottled it in santized brown bottles, using typical sanitary practices. The beer's carbonation is normal, not excessive. Like I said, no idea what I did wrong. And to reiterate, the beer is not terrible, I'm drinking one right now. Just don't get it. Anyone's input is appreciated.
Thanks.

 

[DBhomebrew]

Is this your first time with kveik?

 

[leedspointbrew]

No. I've used regular Kveik yeasts before, in IPAs and Lutra once before in a Faketoberfest. The IPAs did have a little bit of the Kveik-twang that is frequently discussed on these forums, but nothing like this; the Faketoberfest I brewed wasn't exactly Hacker-Pschorr, but a reasonable pseudo-lager facsimile, without the cherry soda aftertaste I'm describing here.

 

[Sammy86]

How is your cleaning and sanitation? Could be a nasty creating that off flavor.

From your recipe I'm not seeing anything directly that would say cherry flavor.

 

[leedspointbrew]

How is your cleaning and sanitation? Could be a nasty creating that off flavor.

From your recipe I'm not seeing anything directly that would say cherry flavor.

Sanitation is fine (I think). Fermzilla and bottling bucket thoroughly cleaned with hot soapy water, cupful of bleach, then Star-san; lid, airlock, bottles basically the same. Pretty much the routine I use on any of my batches. Doesn't necessarily mean it's right, but it's what I do.

 

[jsphlynch]

Although it's not something I've experienced, I've heard of some munich malts giving a cherry-like flavor.

 

[rmr9]

Although it's not something I've experienced, I've heard of some munich malts giving a cherry-like flavor.

I submitted an altbier into competition that had barke munich and caramunich iii and one judge noted a slight cherry note so this could be it.

 

[rburrelli]

You mentioned “aging”. How long was that?

 

[leedspointbrew]

Roughly 4 months.

 

[Miraculix]

Could be a pleasant version of oxidation. Does it go slightly into the direction of sherry wine?

 

[G_robertus]

I second some Munich malts possibly tasting fruity or cherry-like if used in greater quantities. I perceive it as a sweetly malty taste that becomes fruity. That and oxidation like @Miraculix suggested might give you what you're tasting. Maybe they're even related to one another.

 

[leedspointbrew]

Possible. If that's the case, I'm going to have to edit the recipe to reduce the amount of Munich, and see what happens.

 

[dmtaylor]

My bets are on the Munich and/or the Caramunich. I have (rarely) tasted cherry in some examples of imported Oktoberfest beers.

 

[3 Dawg Night]

Is this your first time brewing this recipe?

 

[pvtpublic]

I'm inclined to agree with both the oxidation issue as well as that much Munich combined with caramunich.

I will say this, and it's not my intention to nit-pick though; a schwarzbier is like a German Pilsner, but black. They have almost the same qualities aside from Schwarzbier taking on light characteristics of the roast malts. My personal recommendation would be to mash a Pilsner and add a touch of carafa at the end and just enough to color it.
The recipe you have listed more resembles a Baltic porter. Another awesome style btw.

 

[leedspointbrew]

Is this your first time brewing this recipe?

No. This was the third iteration of this recipe, but the only time that it has tasted like this.

 

[jsphlynch]

No. This was the third iteration of this recipe, but the only time that it has tasted like this.

That would seem to rule out munich malt alone as being the driver unless you switched to a different munich.

 

[leedspointbrew]

That would seem to rule out munich malt alone as being the driver unless you switched to a different munich.

The grain for this particular batch was one of the last sold by my (formerly) LHBS, before the owner closed it and split for North Carolina. I wouldn't be surprised if there were "unexpected" ingredients in it that didn't match what I asked for. I'm not even close to being experienced enough to discern a substitution like that visually, since I had a friend pick it up for me.

 

[Miraculix]

The grain for this particular batch was one of the last sold by my (formerly) LHBS, before the owner closed it and split for North Carolina. I wouldn't be surprised if there were "unexpected" ingredients in it that didn't match what I asked for. I'm not even close to being experienced enough to discern a substitution like that visually, since I had a friend pick it up for me.

Roadkill brew

 

[lumpher]

Being it was 1 of his very last, I'm going to go with your thought about not knowing what was in it. He might have just decided to clean out his bins, sell what he had calling it what you asked for, and hit the road. Nothing stands out to supply that flavor. I doubt contamination is the cause, and not likely oxidation if you used the same process; just some unknown grains.