I have consistently had problems with over attenuation and about to have my worst case ever. Imperial "Juicy" yeast so London III... OG 1.065, currently down to 1.005. had the temp at 66 for a week, gradually raised to 72 for next 2 days to finish off the beer... but it just keeps going. FG should have been around 1.015. I have no doubt this will go down to 0... but how is that possible? Is there just something wrong with my mash process that I'm only getting fermentable sugars out of the grain? I mashed at 150-149 over course of an hour. I get that is on the lower side and I'll get more fermentables... but I wouldn't expect to get 0 body left in my beer. And no.. It's not infected. Looks and smells great, problems is it is going to be as light as water.
Possibly an errant gravity reading. Have you calibrated your hydrometer with distilled water at 60 degrees? Or are you using a refractometer?
No mash schedule ever devised results in only fermentable sugars. If you are getting 100% apparent attenuation with strains like Imperial Juicy, and you are not adding lots of simple sugars after the mash, then there's something at work other than the yeast strain you intentionally pitched. My first guess would be a persistent strain with the STA1 gene. BTW, a gravity of 1.000 doesn't mean "0 body."
Are you thinking he's 10 points off and started at 1.075? Surely he can taste the missing body at 1.005 for an IPA, even with London Ale III.
You learn something new every day. Seems pretty rare. I wonder if he's making different beers with different yeasts since this is not his first bout with "over attenuation".
I'm positive I didn't start higher than 1.065... took refractometer and hydrometer reading, then also have a tilt hydrometer in the beer now. I know the tilt is not going to give me 100% accurate results but over the course of fermentation it will be ballpark and in the last 4 hours it went from 1.010 to 1.005.. I thought for sure it had settled around 1.010 after resting around there for about 24 hours. I will take a proper hydrometer reading when I get home but even if I'm around 1.010, that is still 5-7 points of over attenuation that I'm not expecting.
I've used several different brands of this yeast strain and I always seem to over attenuate at least 5 points. "Juicy" seems to be the biggest work horse though. It is listed at around 75% attenuation.. I'm going to get 92+ it looks like.
If you like that style I'd try upping your mash temp for one batch. Can't hurt really if you're getting that kind of attenuation.
Yeah I think as I'm responding to these questions I'm just realizing that my mash temp is simply too low. I will make a pass at this with 154-155 and see if I can hit the 1.015 range.
Please update this thread when you take a final gravity reading with your other instruments. My view is that a mash temperature of 149°F does not explain this degree of attenuation, and so another explanation is needed. I'm inclined to agree with VikeMan that your fermenter may have an uninvited guest. There was another thread on this forum about a similar (but more extreme) situation, I'll try to dig it up. [Edited to add: here it is. It's actually considerably closer to your situation than I had remembered. In both cases, assuming the readings are accurate, it's very puzzling to me.]
Will do... I was going to dry hop for 2 more days but I honestly think I'm just going to keg tonight to stall any more fermentation. I dropped down to 60 for the time being.
Thanks. Do check out that thread I linked to (which you might have missed because I had to go back and edit my post to include it). I suppose you might be experiencing hop creep, but I'm not sure it can explain such a large drop in gravity. Out of curiosity, though, what was the hop bill?
Thanks I just read through it and now you have me terrified. I'm really hoping this is a combination of a bad gravity reading and too low of a mash. If I end up at 1.010 I will be happy with that and it would only put my attenuation a little too high instead of way too high. Galaxy and Chinook. .4oz first wort and then about 4oz total in whirlpool and ~3oz dryhop.
Update... it's at 1.010. I think my tilt just got stuck in a weird position and freaked out. I think this miss can be chalked up to the lower mash temp
