Hydrometer reading ~ What am I doing wrong?

[BigE]

First off, I'm pleased with my homebrew to date...yeah, yeah, I know relax and have a homebrew...but this is nagging at me. I try to follow the 1-2-3 rule of 1 week in primary, 2 in secondary, and 3 in bottles. For the life of me I just cannot seem to get a proper FG reading? For example my last 6 batches have all had an OG reading of 1.041 up to 1.063 yet when I take the FG reading before bottling the lowest I Have seen is 1.016? With them all seeming to sit at 1.018 or 1.016? The last 3 batches I have even given double time, 2 weeks primary, 3-4 weeks secondary same readings?
I think the beer is ok because it tastes good, all visible signs of fermentation point to it being done. I think the Hydrometer is working as the OG's seem in the right range?
One side note I did a wine for the wife and it seemed right on target OG of 1.096 and an FG of 0.099...the Hydrometer I am using is supposed to be a beer and wine hydrometer...any ideas wtf is going wrong?

[larin1477]

It seems to me your not doing anything wrong...for example your OG reading of 1.063 is a potential Alc. reading of 9%...if you subtract your FG rating of 1.018 which is a PA reading of 2% you get 7% or more alcohol in your beer...which is perfect in my book!
:)...
BTW you have the patience of a rock to give your brew double time...Im lucky to give it the 1-2-3 ...lmao

[BrewDog]

Beer yeast has a typical "apparent attenuation" of in the neighborhood of 70%. "Apparent attenuation" means how much of the gravity will "appear" to turn into alcohol. So, a 1.050 OG beer at 70% attenuation should drop by 35 points.

((1 - FG) - (1 - OG)) / (1 - OG) = apparent attenuation.

Therefore, the FG should be 1.015 for a 70% apparent attenuation yeast.

Now, since alcohol's density is different from water's density, apparent attenuation is not a true measure of "what percentage of the sugars were converted to alcohol", which is what apparent attenuation is kinda trying to measure. This is evident with your wine. You started with a 1.096 must, and ended with a 0.99 wine, which means that the "apparent attenuation" of the wine yeast was about 109.3%. This is illogical, since you can't ferment out more sugar than you started with. That is what makes this a deceptive measure, but it works great for beer making as a quick calculation.

Hope this makes sense.

[BigE]

Originally posted by BrewDog
Beer yeast has a typical "apparent attenuation" of in the neighborhood of 70%. "Apparent attenuation" means how much of the gravity will "appear" to turn into alcohol. So, a 1.050 OG beer at 70% attenuation should drop by 35 points.

Hmm so it sounds like I was off in my original thinking then, for some reason I thought it was more like 75%. So for a beer with an OG of 1.050 then 1.016 is totally ok....thank you for clarifying. Not sure how the heck I had 75% apparent attenuation stuck in my head?

[BigE]

Originally posted by larin1477
BTW you have the patience of a rock to give your brew double time...Im lucky to give it the 1-2-3 ...lmao

Normally I don't but my buddy and I went at it pretty hard to start so having a really healthy stock pile of brews helps!!!!!
We're actually in a position now where we need more bottles for two ready batches an IPA and a Bitter, yum!
I just can't bring myself to buy bottles so I guess I'll just have to relax and crack a home brew, rinse, and repeat!

The weather up here in Ontario is wicked nice this weekend so I'm restocking my empties quickly!!!!!

[dparsons]

Originally posted by BigE
Hmm so it sounds like I was off in my original thinking then, for some reason I thought it was more like 75%.

Beer yeast varies and the apparent attenuation is specific for each variety. Wyeast and White Labs give attenuation ranges for their yeasts as I'm sure other companies do too.

http://www.whitelabs.com/beer/homebrew_strains.html

http://www.wyeastlab.com/beprlist.htm

[BigE]

Thanks dparsons, great link, I did use the Wyeast Scottish Ale Yeast-1728 for my Scottish Heavy and English Bitter and they list that in the 69-73% range so it all makes sense to me know, thanks!

[Quin]

Originally posted by BigE
First off, I'm pleased with my homebrew to date...yeah, yeah, I know relax and have a homebrew...but this is nagging at me. I try to follow the 1-2-3 rule of 1 week in primary, 2 in secondary, and 3 in bottles. For the life of me I just cannot seem to get a proper FG reading? For example my last 6 batches have all had an OG reading of 1.041 up to 1.063 yet when I take the FG reading before bottling the lowest I Have seen is 1.016? With them all seeming to sit at 1.018 or 1.016? The last 3 batches I have even given double time, 2 weeks primary, 3-4 weeks secondary same readings?
I think the beer is ok because it tastes good, all visible signs of fermentation point to it being done. I think the Hydrometer is working as the OG's seem in the right range?
One side note I did a wine for the wife and it seemed right on target OG of 1.096 and an FG of 0.099...the Hydrometer I am using is supposed to be a beer and wine hydrometer...any ideas wtf is going wrong?

If you are using extract, it may be the unfermentables in the extract that are causing the high FG. I ran into the same problem. The only batch I got to ferment any lower was a 1.052 ale using the Muntons Gold yeast. It fermented down to 1.012.

[SirVeza]

Hi,

First lets look at where you are taking your readings. I know that everyone will jump to conclusions, but you and I are aware of Axom's razor. (if not Google it!)

Maybe this sounds impossible, but years ago when I first started brewing, I took all of my hydrometer readings in the little plastic protective tube that came with the hydrometer. My readings were all very high due to the surface effects of the tube, fluid and hydrometer. Hey, no one told me not to this. Don't laugh. I asked around on the Internet and everyone suggested my hydrometer was whacked. I failed to tell them one little detail.

Anyways, nuff said. Where are you taking your readings?

Your gravities are good for your beers and everything tastes ok, then life is good and Gambrinus is happy.

After having a hydrometer for years and then brewing for a while without a hydrometer and can taste the wort and estimate the OG. I can taste the finished beer and estimate the TG and the alc./vol. I truly needed a hydrometer to learn how to do this. Now it's just remembering what it was like.

Your solution is near... use the force.

Dan Carol
Homebrewing In The Philippines (http://homebrewinghobby.blogspot.com/)

[BigE]

LOL, I actually used the plastic case for my first batch...then went to wash it in really hot water only to watch it shrink, warp, and deform because of the heat. I have since bought a proper test vial for the hydrometer. I'm sure it's that I was calculating incorrectly looking for 75% attenuation when the yeast I was using only provides around 70% as BrewDog and others have noted, thanks gang!