Stuck Fermentation?

This is my first time using WY3068 Weihenstephan Wheat. I brewed the NB Dunkelweizen kit on 9/13 using this yeast. I smacked the pack earlier in the day and it was fully expanded by the time I pitched the yeast - I did not brew up a starter for this batch. OG was ~1.054. I substituted 2lbs of golden DME for some of the wheat LME because the kit shipped with the wrong ingredients and I did not realize this until after I started to brew.

I put the carboy in my basement and let it ferment through. Temp was ~64-66 degrees. It had a nice krausen and then fell back into the beer after a couple of days. On 9/27, I racked the beer to a secondary fermenter and sealed with an airlock. Within hours, a thin layer of krausen formed on the surface of the beer and bubbles began pushing through the airlock again. I moved the beer from the basement to my third floor where the beer temp is more around 68-70 degrees. Now, almost three weeks after brew day, the beer is still showing signs of active fermentation. I did not take a gravity reading when I racked the beer, nor did I taste the beer at that time. The beer smells good.

So, my question is, should I be concerned with the fact that this beer is still actively fermenting? I consulted with a few of my homebrewing friends and the only plausible explanation we can think of is that fermentation became stuck, likely due to low temperature and/or low pitch rate, and that fermentation was kick started again when the beer was agitated during the racking process. Bacterial infection is possible, but doesn’t seem likely given a thorough cleaning process during racking and the fact that the beer doesn’t exhibit any off aromas (don’t know about flavors yet).

Any thoughts on these events or your experiences using this yeast strain are appreciated. Thanks.

CP

A gravity reading will ultimately give you the answer.

Here are my thoughts. What you’re seeing is just gas coming out of solution. This can happen when transferring to secondary because you’re stirring things up. When you moved it to a warmer spot, the increased temperature along with the agitation of the move kicked out even more gas and as the beer warms to room temp, more gas will be released.

Now if you saw a big krausen, an inch thick, then you probably did get a second(ary?) fermentation either because you restarted the yeast by stirring them up or you caught a bug. The yeast in the secondary are going to be crazy stressed since you left most of their homies in the primary.

Take a gravity reading and you’ll know the answer for sure. In the future, be sure to check gravity before any transfers to ensure fermentation is complete.

[quote=“mvsawyer”]A gravity reading will ultimately give you the answer.

Here are my thoughts. What you’re seeing is just gas coming out of solution. This can happen when transferring to secondary because you’re stirring things up. When you moved it to a warmer spot, the increased temperature along with the agitation of the move kicked out even more gas and as the beer warms to room temp, more gas will be released.

Now if you saw a big krausen, an inch thick, then you probably did get a second(ary?) fermentation either because you restarted the yeast by stirring them up or you caught a bug. The yeast in the secondary are going to be crazy stressed since you left most of their homies in the primary.

Take a gravity reading and you’ll know the answer for sure. In the future, be sure to check gravity before any transfers to ensure fermentation is complete.[/quote]

this.

wash and sanitize a gravity thief or turkey baster and test the gravity. Activity in the airlock (or fermenter) does not mean fermentation.

If it picked up some lacto or pedio, let is sit another month, bottle it, age it for a year, and tell your homebrew club friends its a sour. they will love it.

Thanks for the tips. I should have taken a gravity reading at the time, and normally do, but it was busy brew day - I also brewed a stout that day - and I simply skipped the step. I’ll take a gravity reading tomorrow and post the results.

Update:

Krausen has fallen back into beer
Temp 70 degrees
S.G. 1.020

Tasted the beer and while it’s not as “wheaty” as a Dunkelweizen should be (due to substitutions), I also did not detect any sour or off flavors. Smells good too. My guess is that it was stuck and the agitation of racking it from primary to secondary kick started the fermentation again. I’ll never know without that other gravity reading. It will be interesting to see where it nets out in terms of F.G.

Update: bottled the beer Sunday night. F.G. 1.012, temp 64 degrees. Tasted really good, so concluding it was stuck fermentation. When in doubt, take a gravity reading. Thanks for all the input!