too much attenuation?

[defenestrate]

well i never thought that i would be complaining about too much attenuation, but let me explain a recent brew. i was going for a munich helles type beer but i fermented with german ale yeast, wyeast 1007. according to the yeast its max attenuation is 76%. i had an OG of 1070, so i was looking for a FG of 1015-16 to have some residual sweetness but still pack a punch. it ended up attenuating all the way down to 1010 for an abv of 7.9 and now it has a very strong alcohol flavor...after 3 weeks in primary, i put it in the keezer to age and thats helped a little but its still a long way off drinkable. i fermented higher than i wanted (upper 60's).
the only aerating that i do is the splashing from the kettle into the buckets, and i usually do make a starter. this high attenuation is pretty common for me, i think the highest FG i've had is 1013 for my stout.
what can i do down the road to have better control of the FG? is racking to a secondary when i reach my target gravity the only option? i prefer to keep my beer in the primary for 3-4 weeks then keg.... thanks!

 

[klamz]

What does the recipe consist of? and is it All-grain

 

[Dos_Locos_Brewery]

klamz has the right questions. If you try to control attenuation by any other means besides mash temperature (and, of course, yeast strain), you risk over-carbonation. If you have consistently high attenuation, it's either too low a mash temp (if all grain) or infection with a super-attenuative strain. If the recipe includes a lot of added sugars, that would explain it, too.

 

[klamz]

yup.....that's exactly what i was getting at

 

[defenestrate]

12.5 lb vienna
2 lb munich

mashed at 151-152

i almost always mash under 154... i guess i didnt trust myself to get enough fermentables if i mashed any higher.

 

[Yooper]

I wonder if your thermometer was off? I found that many of my batches attenuate better than I planned. I now just almost mash at 154 or higher, depending on what I'm making. I made a blonde using S-05, and got a FG of 1.006, mashing at 150.

 

[defenestrate]

I wonder if your thermometer was off? I found that many of my batches attenuate better than I planned. I now just almost mash at 154 or higher, depending on what I'm making. I made a blonde using S-05, and got a FG of 1.006, mashing at 150.

yeah that sounds like me... i'm usually in the 1008-1011 range for everything. i've done the "boiling water calibration" but thats it. maybe its time i step up from the floating thermometer i've had for 2 yrs :cross:

 

[Denny]

according to the yeast its max attenuation is 76%.

No, that's not its max attenuation. The wort decides that more than anything. That's simply a way of comparing the attenuation of that yeast to other yeasts.

 

[BarleyWater]

No, that's not its max attenuation. The wort decides that more than anything. That's simply a way of comparing the attenuation of that yeast to other yeasts.

+1, its MAX attenuation is 100%, it just depends on the source of it's fermentables. The 76% number is just referring to a "typical" wort as defined by their lab, your wort may have had more fermentable sugar, giving you a higher attenuation.

 

[Synovia]

+1, its MAX attenuation is 100%, it just depends on the source of it's fermentables. The 76% number is just referring to a "typical" wort as defined by their lab, your wort may have had more fermentable sugar, giving you a higher attenuation.

Not only that, but what we're looking at is usually "apparent attenuation". Full, 100% fermentation, will take you down below 1.000, while most HB'ers think 1.000 is 100% fermentation.

 

[defenestrate]

that all makes sense, thanks guys!

 

[Dos_Locos_Brewery]

Agreed - it's not the yeast. I've used Wyeast #1007 many times - it's my house favorite. I've never seen attenuation like that, and I mash at ~150F. With a grist of Vienna + Munich, I'd guess you'd be pretty hard pressed to explain that kind of attenuation from thermometer calibration. Have you ever tinkered with one of those super-attenuative strains that might have "occupied" your brewery?

 

[david_42]

I'd take it out of the keezer and stick it in a cool place until Thanksgiving.

 

[defenestrate]

Have you ever tinkered with one of those super-attenuative strains that might have "occupied" your brewery?

do you mean like us-05? if so, yes i use 05 a lot and i've gotten 88% attenuation with it in my amber ale.

I'd take it out of the keezer and stick it in a cool place until Thanksgiving.

this sounds like a good idea... having it age in the keezer has mellowed it out a little but maybe i'll just take it off the gas, leave it carbed up and age in my basement for another month and just forget about it.