Infection or Fermentation?

[Hoont]

I brewed a pale ale on Sunday; OG of about 1.047. I added Wyeast 1272 American Ale II yeast and that baby was fermenting like crazy within 12 hours (I made a starter), ferementing at 67. By Wednesday, fermentation was pretty much done. I waited till thursday to dry hop. Thursday I took a refractometer reading and it was 1.005. I added my dry hops and took it upstairs to finish. I have it set to 68.

Friday morning I take a look to check on it and it has about 1 inch of white foam. I was quite surprised fermentation restarted cause there ain't much left to ferment. I get home from work, take a look and it looks the same. I look closer and there are small white chunks forming on the top with the foam. So I swirled it a bit and those white bits went sinking to the bottom.

Is this an infection or is something with the 1272 yeast? I've not used this yeast before... and I've never had a fermentation like this.

[BeaverBarber]

I brewed a pale ale on Sunday; OG of about 1.047. I added Wyeast 1272 American Ale II yeast and that baby was fermenting like crazy within 12 hours (I made a starter), ferementing at 67. By Wednesday, fermentation was pretty much done. I waited till thursday to dry hop. Thursday I took a refractometer reading and it was 1.005. I added my dry hops and took it upstairs to finish. I have it set to 68.

Friday morning I take a look to check on it and it has about 1 inch of white foam. I was quite surprised fermentation restarted cause there ain't much left to ferment. I get home from work, take a look and it looks the same. I look closer and there are small white chunks forming on the top with the foam. So I swirled it a bit and those white bits went sinking to the bottom.

Is this an infection or is something with the 1272 yeast? I've not used this yeast before... and I've never had a fermentation like this.

Refractometer readings aren't too reliable post-fermentation. I'd take a normal hydrometer reading. 5 days is a little early to start thinking infection. I've used 1272 before because it's the Brew Dog strain. I don't remember anything out of the ordinary, and I'm not sure that little white islands of stuff that sinks to the bottom is too unusual. My guess is that you're alright.

[Ozwald]

With a refract reading of 1.005, I can only assume you made both temp & fermentation corrections, so I don't see a problem there; you might be a point or two off, depending on how anal you are about your test samples, but nothing significant enough to make me think you're getting an inaccurate reading. I'm not much of a Wyeast guy, so I don't have any direct experience with that strain. How accurate are your controllers? Is it possible that the 67 was a little low & the 68 a touch high? Warming it up a couple of degrees could have kickstarted the yeast still in suspension. I've had that with 001 before - raise a couple degrees, the yeast think they can ferment more... for about a day... then they settle back down. The strains are somewhat similar, so that would be my first guess. Everything else seems to line up.

[Hoont]

Thanks all; I am going to go on the assumption that for whatever reason the yeast stopped fermenting and the movement of going upstairs and oxygen from adding the dry hops cause the yeast to stir back up (and the additional degree or two of temperature). It will be interesting to see what this finishes out at... thanks again for the replies

[BeaverBarber]

Thanks all; I am going to go on the assumption that for whatever reason the yeast stopped fermenting and the movement of going upstairs and oxygen from adding the dry hops cause the yeast to stir back up (and the additional degree or two of temperature). It will be interesting to see what this finishes out at... thanks again for the replies

I was wondering if you wouldn't mind updating this thread with your final findings. I'm not thinking there's anything wrong with your beer, but I'm interested to know if your beer tastes ends up tasting like green apples.

[Hoont]

I will do so... When I added the 1st round of dry hops and took a refractometer reading it tasted good. This is intended to be a scaled down take of Bell's Two Hearted Ale. Good Stuff.

[spiderwrangler]

If you didn't adjust your refract for it being post ferment, it will read a bit low, you may have been about 5 points higher... depending on how far this finishes out, you might have had enough to kick up some additional fermentation.

[Ozwald]

If you didn't adjust your refract for it being post ferment, it will read a bit low, you may have been about 5 points higher... depending on how far this finishes out, you might have had enough to kick up some additional fermentation.

Without an adjustment if his refract is reading 1.005, his corrected gravity would be down in the .9's which is why I assumed he already made the correction.

Edit: Not doing the exact math was bugging me. If your refract was reading 1.005 on a 1.047 OG beer, corrected FG =.981