What caused a secondary fermentation?

[kanddr]

Short version:
I have a second fermentation going 4 days after I racked to secondary and dry hopped. Why?

Long version:
I brewed a Dogfish Head 60 clone on 5/25 and let it sit in the primary for 2 weeks. OG was 1.064 (right on the money) and FG on 6/8 was 1.016 (1.019 is anticipated per instructions). I used 2 vials of WLP002 at pitch time.

I only took one FG reading on 6/8 because the krousen had fallen days before and there was no activity for several days so I figured it had finished fermenting. I racked over to my secondary for 1 week of dry hopping with 1-1/3 oz of pellet hops and they sat on top for a few days then fell. Well, tonight which is 4 days since dry hopping, I have active fermentation again! There is a small krausen on top with visible swirling of yeast and hops just like in a primary fermentation and I have bubbles out of the airlock at about 1 per 10-15 seconds.

What would have caused this? There wasn't any sort of activity like this in the primary after the initial fermentation nor in the secondary until today. Could hops added any sort of fermentables to cause this?

 

[iambeer]

Not sure man, I'm a newb. All I can think about is how my 1 gallon DME test has started bubbling again and won't stop and obviously has other things growing in it besides yeast. I hope that isn't the case for you.

 

[Dunerunner]

Could have been something hanging out in the secondary fermenter, something in the hops or just very happy agressive yeast.

If everything was clean and the hops are not suspect, relax. It will be beer.

 

[kanddr]

I'm not too worried about an infection but was wondering if anybody else has experienced this or would know what caused it.

 

[smokinj]

What is your gravity now? It is very common when transferring to a secondary vessel, especially with dry hops, for it look like active fermentation has started. Usually it is just co2 coming out of solution and air being released from the hops. Highly doubt there is any reason for concern, and you will probably end up with the same or a very close FG.

 

[AmandaK]

Sometimes adding hops in the fermenter causes the beer to off gas after fermentation is complete. It's not actually fermentation, it's just bubbles.

Have you taken a gravity reading to confirm that it is indeed fermenting again?

 

[kanddr]

I'll take a reading in a couple days when it has been 7 days in the secondary for the dry hop. If it hasnt moved down more then I'll go ahead and bottle but if it has dropped then I'll keep it in there longer. Thanks everybody.

 

[pjj2ba]

Also, there's food in them there hops. They are not just alpha/beta acids and oils. Plenty of sugars in them. Not enough to change the gravity, but plenty enough for the yeast to get all excited about.

 

[matt-tastic]

There could have also been residual active yeast that for whatever reason went dormant in your primary. once they were racked to the secondary, the came back alive (ZOMBIE YEAST!!!) and started eating the residual sugars in the beer and from the hops.

You'll be fine, you just may end up with a little more alcohol content when you're done, due to a lower FG.

 

[kanddr]

It dropped from 1.016 to 1.014 in the secondary. Obviously, there was some fermentation going on but most of it was probably off gassing. I'll wait a little while longer then bottle but boy does it taste goooood now!

 

[Dan]

It dropped from 1.016 to 1.014 in the secondary. Obviously, there was some fermentation going on but most of it was probably off gassing. I'll wait a little while longer then bottle but boy does it taste goooood now!

The post I read said "It dropped from 1.106 to 1.014 in the secondary..." but when I quoted you it changed to the above, you must have fixed your post. ha ha.

Sounds like everything is going well! Congrats!

 

[kanddr]

The post I read said "It dropped from 1.106 to 1.014 in the secondary..." but when I quoted you it changed to the above, you must have fixed your post. ha ha.

Sounds like everything is going well! Congrats!

Yep, I noticed the error and fixed it.