Low Attenuation

Quick question. I’m getting higher than expected FG’s and my attenuations are only in the mid 50’s to low 60’s. I’ve been hitting the target OG’s for almost all of my recipes (extract and partial mash) and I try and keep the temps to the mid to upper 60’s during fermentation for at least 3 weeks in the primary. Would using a yeast starter help with this issue? I’ve been keeping a pretty accurate eye on my mash and sparge temps. For instance I made the Little Bear CDA partial mash and I got a OG of about 1.045/1.046 and after three weeks I’m at 1.015, which is a little high as I was expecting something in the range of 1.011 so the Real Attenuation is in the 54ish range. Any recommendations on how I can lower my FG and raise my attenuation?

Thanks!

[quote=“TFrankMac”]Quick question. I’m getting higher than expected FG’s and my attenuations are only in the mid 50’s to low 60’s. I’ve been hitting the target OG’s for almost all of my recipes (extract and partial mash) and I try and keep the temps to the mid to upper 60’s during fermentation for at least 3 weeks in the primary. Would using a yeast starter help with this issue? I’ve been keeping a pretty accurate eye on my mash and sparge temps. For instance I made the Little Bear CDA partial mash and I got a OG of about 1.045/1.046 and after three weeks I’m at 1.015, which is a little high as I was expecting something in the range of 1.011 so the Real Attenuation is in the 54ish range. Any recommendations on how I can lower my FG and raise my attenuation?

Thanks![/quote]

that does seem low. have you calibrated your hydrometer (test in in distilled water and it should read 1.000)?

are you using darker extracts?

I’ve calibrated both my hydrometer and refractometer. I did use 3 lbs of Briess Dark DME. I’ve heard that the dark extracts can affect FG and attenuation, is that true?

it is true. dark extracts have a lot of unfermentables sugars in them, which will leave excess sugar after fermentation that the yeast won’t digest. resulting in higher FG. have you used dark or gold extract in all your batches? if so, this could be your issue

although 1.015 isn’t terribly low. i’m sure your beers will still be good

All extracts will lead to a higher final gravity compared to all grain. Darker extracts even more so. Color is always a little darker when using extracts.

Yeah, I’ll blame it on the extract too. I was thinking yeast starter initially would help but you should be able to get by with a 1.0455 wort as long as it was fresh.

Thanks everyone. That’s probably the culprit then. What levels of attenuation do all of you usually get?

I’ve been getting pretty good attenuation lately, right around the suggested range most often but I did just overshoot what I was planning for also in a low temperature mashed California Common in which I got about 83%. I didn’t really track this stuff back when I did extract but I do remember our beers being a bit sweet; especially the bigger ones.

Well according to the estimates provided to me by iBrewMaster I seem to have reached near or at the estimated FG provided by my other beers (partial and extracts,) however those values seem a little bit high for the suggested attenuation listed on the yeast packet (the typical 70-75%) range. Is that typical? I seem to only hit in the 60’s range even when I nail the OG and estimated FG.

[quote=“TFrankMac”]however those values seem a little bit high for the suggested attenuation listed on the yeast packet (the typical 70-75%) range. Is that typical? I seem to only hit in the 60’s range even when I nail the OG and estimated FG.[/quote]The attenuation listed for each yeast is not intended to be an estimate of the attenuation that you will achieve with your beer - the number should be used only to compare a given yeast versus another yeast from the same manufacturer (they are fermenting a consistent wort with a fermentable profile that likely is not anything like your wort).

10-4 Thanks!