Starting gravity and efficiency calculations are wrong (103% brewhouse!?)

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JRTurner1234

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Hi,

Wwwoooo!! 103% efficiency - except that clearly can't be right!

I can't work out where I am going wrong with my efficiency calculations / mashing.

Here is my recipe:

d94b86278d.png


Water requirements:

d94fc6143d.png


Notes
I did get 27.1 litres pre-boil into the kettle as expected.
However, I ended up with 24 litres into the FV (instead of 20 litres).

Mashing process:

d97fc7c9f3.png




Efficiency calculations:

d96213d5fd.png



Gravity readings

pre boil gravity 1.0052 (27 litres)
SG was 1.062 (not 1.055 as per the recipe)

Additional Information

I weighed and measured the grains and water carefully (not drinking beer and with another person checking!).

I've checked the gravity readings using two hydrometers.

Confused!!

Any help much appreciated! This is the third beer in a row that has come out with a higher starting gravity than anticipated, so I'm clearly doing something odd.

I'm sure I need to provide more information to get to the bottom this - ready to answer any questions!!

Thanks,
JRT
 
Something is amiss. Either the temperature that you checked your gravity at was off and it gave a false reading or you added some extra fermentable somewhere.

Could you have made a mistake with your scales. Did you tare them by accident and add too much sugar?
 
How did you measure volume? The markings on fermentation vessels are notoriously inaccurate.
 
Thanks @DoctorMick and @Simonh82

Your insights have been very helpful!

What temp did you do the pre/post boil gravity readings at?
Click to expand...
- All my readings were taken at 20C, measured with thermapen

However, this did get me thinking about my gravity readings. I've just re-read and maybe I read from the bottom of the menicus, rather than the top. I've posted my photo below. It's a bit difficult to see, but I now think my reading should be 1.060, rather than 1.062.

What was the expected pre-boil og?
Click to expand...
- Expected pre-boil og was 1.40 (I got 1.52)

How did you measure volume? The markings on fermentation vessels are notoriously inaccurate.
Click to expand...

Wow! I've just double checked my FV and going on the markings on the outside, it's 21.6 litres full, not 24 litres like I thought I saw before!

Bit of an optical illusion on the scale because it has 20 litres on one side of the scale line and 5 gallons a few centimetres above. I misread this and deduced there was 24 litres in the FV!

So, with my amended readings, my efficiency calculations now look like this:

f2d3c5a7d6.png


So now my brewhouse efficiency calculates at 89%, which feels more realistic (but still higher than anticipated or planned for).

What do you think? Case closed?
 
A brewhouse efficiency of 89% is achievable but is pretty hard to get. I managed it a couple of brews ago with my BIAB system. The key for me was milling my grain very finely and getting almost no losses along the way. I squeezed the hell out of my grain bag, did a double dunk sparge and got almost my entire kettle into the fermentor, leaving maybe only 1L behind to deadspace and hop absorption.

With the various losses along the way in your system I think it would be quite tricky to get to 89%.

I did have another thought. Did you include the corn sugar as a late addition or did brewer's friend calculate include it in the mash. If so the fact it was (i assume) added to the kettle rather than the mash might give a slightly higher BHE although as it was a small addition it was probably only 1-2%.
 
@simonh82

hhmmm...interesting.

I did indeed add the sugar straight into kettle.

Is there any way I can account for this or take it into consideration in my calculations?

Cheers,
JRT
 
When you add the sugar there should be a drop down which allows you to select late addition. This calculates it as an addition 10 minutes before the end of the boil.
 

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