skarp0ye
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Absolutely, will follow this thread and analyzeIn general, do you see the value of it based on the discussion here?
Absolutely, will follow this thread and analyzeIn general, do you see the value of it based on the discussion here?
If you’re using 1kg of grain with 80% potential, that’s 0.4L less water you need to start with.
After tinkering with doug293cz's spreadsheet and following this and similar threads, most examples use 80% FGDB, 4% grain moisture content, 37 as the weighted grain potential and 100% conversion efficiency (ie: 80% mash efficiency). Is it safe to say that those are default values to be used in the majority of recipes?
Ahh, thank you very much this helps, reworking my formula now.To be precise, you have to calculate the weighted average based on all malts in the bill.
For your example, 23.5 is 97.9% of the grain bill, and 0.5 is 2.1%. Multiply their respective PPG values times each percentage, and add the resulting products. You'll get 36.958 PPG as the potential for the whole grain bill.
To be precise, you have to calculate the weighted average based on all malts in the bill.
For your example, 23.5 is 97.9% of the grain bill, and 0.5 is 2.1%. Multiply their respective PPG values times each percentage, and add the resulting products. You'll get 36.958 PPG as the potential for the whole grain bill.
37 x 0.979 = 36.223
35 x 0.021 = 0.735
36.223 + 0.735 = 36.958
Thank you but @McKnukle's approach was easy enough to do.@ScrewyBrewer or just use a general weighted average formula (without explicitly computing percentages first). Whichever is easier given your starting point.
(23.5 x 37) + (0.5 x 35)
------------------------
23.5 + 0.5
After tinkering with doug293cz's spreadsheet and following this and similar threads, most examples use 80% FGDB, 4% grain moisture content, 37 as the weighted grain potential and 100% conversion efficiency (ie: 80% mash efficiency). Is it safe to say that those are default values to be used in the majority of recipes?
Another question regarding a congress mash. Do I enter 36 ppg as the weighted grain potential for a recipe that uses 23.5 lbs of 37 ppg malt and 0.5 lbs of 35 ppg malt?
I'm afraid you've lost me, I was really focusing on the 4% moisture content...I was wrong in my original assertion in the post you quoted. When I said water boil off + absorption = total wort and not total water. It is indeed total water because grain absorption is understood to be apparent grain absorption (the difference between starting water and wort volume after bag removal) and not real absorption (the difference between wort before and after pulling the bag). Therefore my claim of extra 0.4L was incorrect. In any case, the spreadsheet handles this correctly.
You have quoted me in an earlier post today.I'm afraid you've lost me, are you referring to a different post?
Yes, thank you. I see now where the confusion may have started.You have quoted me in an earlier post today.
@ScrewyBrewer after some careful reverse engineering, I have got Brewfather and Doug's spreadsheet in sync within one gravity point, at least up until the OG gets very high as is described above. What is the sample pale ale recipe and what is Daniel's advanced gravity calculation that you reference?
Thank you.For one thing, you can't use post-boil volume for a mash efficiency calculation. Mash efficiency evaluates wort collection at the pre-boil stage. The "gallons" in points per pounds per gallon are of wort during the mash. So the volume in that equation will be a higher value, and the division portion will yield a smaller figure, yielding a lower efficiency value.
What are the water volumes you are entering into Brewfather? I'll try it as well.
Cheers @Wolffie and best wishes.
Knowing a bit of brewing math won't produce good beer. But it's enjoyable to understand what's going on, and that helps us aim for a particular end product.
I think for me, understanding leads to consistency which gradually dials out the "oops" factor, leading to predictability and confidence. I definitely make a few sub-par beers among the really good ones, but it's due to poorly constructed recipes rather than process/technique. And that's how it should be, I think.
FWIW, BrewCipher asks the user for mash efficiency for a given recipe. Using that, in conjunction with the user's brewhouse parameters (e.g. mash tun dead space, xfer losses, boil off rate, etc.), its mash efficiency predictor tool calculates an expected mash efficiency for any size grain bill and/or a change from batch sparge to no-sparge or vice versa.
I agree that conversion efficiency is definitely key. But, as you mentioned, most users don't know their conversion efficiency (or often, even what that means). The math can derive the conversion efficiency behind the scenes, given grain bill size, mash efficiency, and brewhouse parameters.
That said, for educational purposes, I would take Doug's stuff before all others.
Reviving this briefly, to agree with @VikeMan and add my $.02 regarding mash efficiency calculators and conversion efficiency. I'm a little frustrated that none of the popular calculators have conversion efficiency as a variable, and resulting First Wort gravity estimate. With so many people moving to BIAB and no sparge systems, this seems like a big miss in the calculators. Having to adjust my mash efficiency up for low gravity beers and down for high gravity beers is a PITA. In my perfect world, I could set conversion efficiency to 97%, and then target the right first wort gravity for my boil off. Grain absorbtion, dead space, and other mashtun losses are basically fixed, so no-sparge systems should have mash efficiency calculated from conversion efficiency.
I see that Brewfather has added "conversion efficiency" as a an "Experimental Feature". Does anyone know if this affects anything? As far as I can see, it doesn't impact any values in recipe creation, and the description which says it "allows you to ... track first wort gravity" also doesn't seem to be implemented. Is there any plan to get this added? At the very least, if there's a calculator for "first wort gravity" on the recipe creation page, I can adjust my mash efficiency to get to the right first wort gravity for full volume mashes.
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