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Missed OG

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gcam333:
I brewed my second batch this weekend. Decided to semi come up with a recipe that I would call a big IPA. I used the calculator on tastybrew. I tried to be very precise even used digital scales and a stopwatch . According to the calculator my OG should have been 1.066, Actual was 1.073. Is this within the normal margin of error? I also made a starter out of SA-05 because of the high OG and have had a good strong fermentation for 36 hrs. I'm pretty sure I have enough yeast to finish it off.
I'm learning slowly.

tygo:
I'd say that you underestimated your efficiency a bit but we'd need more info to be able to help you figure out what happened.  Post the recipe and your assumed efficiency.

gcam333:
Boil Vloume 3.5
Batch size 5.25

5.68 lb DME
2.2 lb LME
1.25 lb Crystal 60
.25 Special B

1.0 Hallertau Tradtion  @ 50
1.0 Fuggles @ 30
1.0 Cascade @ 20
!.0 Cascade @10
1.0 Cascade @ 2

Target OG was 1.066    Actual was 1.073   assumed efficiency was 75%
Target FG was 1.017
58 IBU

abraxas:
Two things...

Under-pitching a little isn't going to make too much of a difference.  Don't worry about it.

That being said, it probably wasn't necessary to make a starter with the S-05.  Jamil's calc: http://www.mrmalty.com/calc/calc.html  lists a 263 billion yeast cell count as optimal for a 1.073 beer which equates to (1.3) 11.5 gram packets.  I am sure whatever size starter you made put you well into that category.  Had you just pitched the packet, you would have been a little light which might have resulted in a few more esters but for your second brew there's probably a number of other more important things you should be worries about.

As to why you have a high OG, I'd guess temperature correction and hygrometer calibration could be one reason.   Double check your hygrometer in water and use a correction table: http://www.ebrew.com/primarynews/ct_hydrometer_temp_correction.htm
My last hygrometer read high by .002 points for some reason, probably just because it was a cheap one not checked closely at the factory.

Also double check your final volume.  You may have boiled off more than you were expecting leaving you with less liquid and a higher final resultant gravity.  This is easily remedied by adding sterile makeup water.

tygo:

--- Quote from: gcam333 on April 26, 2010, 07:52:20 PM ---Boil Vloume 3.5
Batch size 5.25

--- End quote ---

Since you topped off after boiling it could be that the beer was not evening mixed when you took your sample.  But that usually leads to a lower OG reading when topping off so what abraxas said is more likely.  Either an inaccurate hydrometer or your volumes were a little off.

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