Higher Than Expected OG

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beerspitnight

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Gents-
Brewed a Belgian PA today, recipe for the 10 gallon batch is below:

Pale 17.63 83%
Vienna 1.1 5%
CaraMunich 0.55 3%

also added in 2 lbs of invert at the start of the boil.

First pull reading was 1.065 - spot on. Last pull reading was 1.024. Forgot to grab a pre-boil reading.

Mashed for 60 min @ 156

Boiled for 60 min

Expected OG, based on CP's brewsheet thingy was 1.056 and we came in at 1.064. What could have caused our OG to be so significantly higher?
I am not upset about this, just wondering how it happened...
 
What was your post boil volume, i.e. the amount you put into the fermenter? Was this a top off in the fermenter batch, or a full volume boil?

One thing also to take in consideration, especially if your only a few points of, is that there might be a discrepency between the true extraction potential of your grain and the "theoretical" number that is used in our software, the reality is always there that your batch of grain that you mashed could be more or less able to convert for whatever reason.
 
Revvy-
Post boil volume was 10gal, or right there abouts (just a hair under the lower bolts, which is, from our calculations, 10 gallons...we are really scientific-like over here in the 'Jing!) And it was a full boil volume - no top offs.
Fair enough on the conversion aspect - again, I am not unhappy about being over on our OG, it is just going to be a stronger beer than we anticipated on making.
Every batch is a learning experience, although sometimes a bit of a drunken one!
 
Another thing to consider is your efficiency vs what the efficiency of the software to create the recipe was set at.

I've always set mine for the default 75% in most brewing software, but I just got a new grainmill for my birthday, a barley crusher, and I'm still dialing my crush in, and I've been over shooting my almost all my gravities lately, because I'm getting a better crush than before. So I have to tweak my software efficicency a bit now.
 
Revvy said:
Another thing to consider is your efficiency vs what the efficiency of the software to create the recipe was set at.

I've always set mine for the default 75% in most brewing software, but I just got a new grainmill for my birthday, a barley crusher, and I'm still dialing my crush in, and I've been over shooting my almost my gravities lately, because I'm getting a better crush than before. So I have to tweak my software efficicency a bit now.

+1 on this. I am far from an expert on brewing but, I have recently started calculating my efficiency. I also just recently got Beersmith. I have been getting about 85% and thought this was too good to be true so, when i wrote my last recipe, I set it for 75%. I over shot my gravity by about ten points. Live and learn. I guess it will be a strong Irish ale.
 
This is kind of what I suspected. I set my efficiency to 75 and figured I must have got a little higher than expected.
 
Looks like you got about 80% efficiency, which is what I get with my current equipment. Hopefully, your efficiency will not vary very much from one brew to the next, in which case you can cut down on the malts a bit to achieve the required OG. If your efficiency does vary from one batch to the next, then you need to take careful notes and try to establish why this happens, and to adjust your procedures to eliminate the variations.

-a.
 
All good points. My only follow up question (at least for now) is that we hit the first and last pull gravity readings spot on as according to the chart - how can our final OG be so much higher then? Can we not assume that since those numbers were spot on according to the chart that our final numbers should also be reflective of the chart?
Thanks!
 
beerspitnight said:
All good points. My only follow up question (at least for now) is that we hit the first and last pull gravity readings spot on as according to the chart - how can our final OG be so much higher then? Can we not assume that since those numbers were spot on according to the chart that our final numbers should also be reflective of the chart?
Thanks!

1) even if the gravities are spot on, if the volumes are different, the total gravity can vary.

2) your boil of rate will significantly impact your OG, so you could be spot on for preboil gravity and still be off on OG if you boiled off more or less than the recipe assumed.
 
were you cooling your gravity samples before you checked them? If you are measuring gravity when the wort is still hot it will read lower than it actually is.
 
Sounds good you got more efficiency from this batch. Remember the numbers are fluid one persons 70 % eff will change if yours are different.
 
Eme, yes the wort was chilled correctly.
Wind, I am happy with 80% efficiency!

So here is the next question - how do you guys go about measuring your post-boil volume? What is the easiest way to go about doing this?
 
Ladies & Gents-
Took a gravity reading of this beer yesterday - .008! which is below the .013 we wanted. That is showing an Actual Attenuation of 88%! Holy crap - this beer is going to be dryer than we wanted. What would cause this? 2# of invert? Over pitching? Mad, Mad Chimay yeast?
 
What was the temperature, and what temperature is your hydrometer calibrated to? If your beer temperature is higher than the hydrometer calibration temperature, then that could give a low reading.
Have you checked that your hydrometer is accurate by checking the gravity of water at the calibration temperature? I've had hydrometers that recorded a gravity of 1.004 with distilled water at the calibration temperature.

-a.
 
-a - temp was correct when gravity reading was checked. I will be sure to do a calibration on it as well.
 
+1 on hydrometer calibration. Last night I transferred a brown ale to secondary for dry hopping and my gravity was 1.020, was looking for 1.015. Odd thing was it tasted great, not cloyingly sweet as I would have expected with that reading. I did a quick check on my hydrometer with tap water and got 1.004. Past checks with the same water always came up 1.000. Getting some distilled water today to confirm the readings but I suspect my beer is closer to my anticipated gravity than the hydrometer shows.
 
Checked the hydrometer last night - 1.000 on distilled water...
Guessing the addition of invert/too much yeast took us down to 1.008?
 
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