LONG Fermentation - Question

Hi all,

Been brewing for about 1.5 years and have made at least a dozen batches with all but one being all grain. I use batch sparging and use an calculator to raise the grain bill to make up the difference in efficiency.

I made a hefeweizen using White Labs WLP300. I pitched the yeast two weeks and two days ago and I am still getting a bubble every 3-5 seconds in one of those 'tripple ripple' airlocks, the one that looks like a sideways 'S'.

I have never seen fermentation take this long. Usually, it gets a week in the primary, a week in the secondary and it is done. I did do two things slightly different this time that one would assume could cause this to happen:

1) I made a REALLY big starter. I never made a starter before (just made myself a killer stirplate just to make starters) and just pitched the White Labs tube and all was good. I had some yeast I preserved in the deep freeze about a year ago that I pulled out a week before and added to some boiled DME because the order I placed from AHB was stuck in a warehouse somewhere and the yeast was sure to be dead when it arrived. Then when the order arrived, I tried to make a starter out it too. It took three days to get active fermentation in the flask using the stirplate, but it woke up. They were both the same strain of yeast, so I figured what the heck and combined them together to make a huge starter. I had active fermentation in just under two hours.

2) I added BrewVint alcohol booster, a highly refined corn sugar that is added during the last 15 minutes of the boil. It is supposed to boost alcohol by 1% in the finished product.

I took gravity readings before racking into the primary and again after racking to secondary. Gravity was at 1.062 before going into the primary and last reading was 1.016 when going into the secondary, a hefty 6% ABV, certainly already at the 1% boost I was looking for. I consistently get 5% out of the recipe I use for hefeweizen, and since it is my favorite brew, I almost exclusively make it. Of the dozen or so that I have made, four have NOT been this recipe.

I know that most yeast can only tolerate a certain alcohol %, but after two weeks and two days, the airlock is still bubbling and you can see the fine little bubbles percolating up the side of the carboy! Granted I dont have all the experience in the world, but after a dozen or so batches, I wouldn't call myself a novice either.

Any opinions? I will certainly let it sit until it quits bubbling, but just wanted to get some input on this. There are no signs of infection and it has been sitting at 70F the entire time.

Thanks in advance,

Dean

have you checked the gravity since putting it in the secondary? at 1.016 it could loose a few more points after being racked but that would likely happen within a few days. Only sure way to know if your fermentation is done is the gravity. The bubbles could just be off gassing which can go on for a couple weeks, though usually not that vigorously.

take a few gravity readings over the next week if its stays the same then its done. The off gassing isnt a problem. it will just speed up keg carbing or come out when you rack into the bottling bucket and bottles.

hefeweizens can offen appear like they are still rolling when the fermentation is in fact finished.

if you've reached your final gravity, feel free to keg or bottle. of course, it won't hurt to let it sit another week, either. hefeweizens are good young, but are best at around six weeks IMO.