Automatic Calculation Tool of Mash Efficency and BH Effic.

General discussion on BeerTools Pro Software.
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bzwrxbz
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Post by bzwrxbz »

Ok, I found some interesting info on this at HBD

Mash Efficiency Vs. Brewhouse Efficiency

Ok, if you're still with me this far, it's time to split a few hairs.

Some people calculate their efficiency based on the volume and gravity of pre-boil runnings. This gives the efficiency of the mash and sparge alone, which I refer to as mash efficiency.

Other people calculate their efficiency based on the volume and gravity of wort that actually goes into the fermenter. This gives the overall efficiency of the entire brewing process -- the brewhouse efficiency.

What's the difference? Well, the decrease in volume which occurs during the boil actually has no effect, since the decrease in volume is accompanied by an increase in specific gravity -- i.e., the total amount of sugar remains the same. What does have an effect is the fact that some wort is typically left behind in the boiling kettle, with the hops. This means that the brewhouse efficiency will always be a few points lower than the mash efficiency, because some sugar is left behind.

Which method is the "right" one? They both are; either one will work. Just pick one method, and stick with it, so that your records are consistent. Or, if you tend to be anal on the recordkeeping side of things, just record both sets of numbers!


at this link... http://hbd.org/uchima/tech/efficiency.html

i am sure way down the line something like this can be implemented in BTP. I tend to measure both pre and post boil gravities...

cheers!
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slothrob
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Post by slothrob »

As a bit of an aside, I only measure pre-boil SG, pre-boil volume, and post-boil volume.

I measure pre-boil SG and volume to get mash efficiency, but primarily to make any final adjustments to the bittering hop addition so that I end up with the beer I intended to make (or at least a drinkable one). A couple times I've also fallen low enough on SG to warrent adding some DME to salvage to batch.

I measure post-boil volume to check boil-off volume and see if I hit my target SG. To some extent, I consider the post-boil SG a point of curiosity, while the pre-boil SG is neccessary to produce a predictable beer.

I calculate my actual SG based on the other numbers: (post-boil SG)=[(pre-boil SG)*(pre-boil volume)]/(post-boil volume).
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