Bottle-to-Bottle Off Flavors

[Pancoastbrewing]

I posted this in the all grain forum and had no replies...

Brewed a 3 gallon AG Munich Helles. Used 2 saflager s-23 dry yeast packets. Had a normal fermentation (52 degrees on the temp controlled fermenter) and a 35 day lager period. 3 weeks room temp bottle carb. Came out very well for the most part. Only issue is that I'm noticing some bottle to bottle inconsistency which I haven't experienced before. This is my first time using s-23 (usually use saflager 34/70) and I expected it to be a bit more fruity. I've noticed that most bottles have a slight sulfury aroma (somewhat ok for a Helles), while some have a strong banana-y, almost Hefeweizen type aroma and taste. Reminds me a lot of franziskaner hefe. It really tastes like two entirely different brews. There are no other noticeable differences between the sulfur and banana bottles as far as color, clarity and sediment.

Any ideas what might be going on here? I'm stumped.

 

[jwalk4]

Sorry no one read your thread, but that's a weird problem to have.

When flavors vary from bottle to bottle, I always advise checking your sanitation. But Sulfur and Banana-esters aren't usually the product of infection.

Consider below:

Give your beer more time. Lagers, in particular, need time to mellow and become less rough around the edges, and part of this maturation is the release of sulfur. If you keg or bottle too early, you may be trapping hydrogen sulfide in the beer.

Buy some yeast nutrient. All-malt wort usually contains everything a yeast cell needs to conduct fermentation, but depending on your malt and water profile, your wort may be short on zinc or nitrogen. Adding some nutrient might help.

Consider your yeast strain. Some lager strains are simply more sulfuric than others. In my case, it was a Munich lager variety, which makes excellent beer, but also makes a terrible stink. Mexican lager and American lager strains are sometimes less sulfuric than their Continental counterparts, but experimentation is key.
Carpenter, 2014

 

[Pancoastbrewing]

Yeah, it has me stumped. I've treated every bottle the same, yet some bottles will taste really good and definitely close to style while others taste exactly like a Hefeweizen. I've read some negative stuff about s-23, but they mostly have to do with that yeast producing a batch that is more fruity and ale like.

 

[SeraW]

Wild yeast halfway through bottling regimen? Does seem unlikely, but I remember reading about a failed Brulosophy experiment where a wild yeast was responsible for an unexpected banana bomb.

 

[Pancoastbrewing]

I'll chalk it up to the yeast. Unfortunately I've had to use the s-23 more often because my LHBS has been out of the 34/70. I'm usually pretty good with sanitation.