[EDIT: Phil, a few hours after writing the below, I re-read your question and think I might have missed a few essentials. Too many beers today
. I'll look at it again tomorrow - hopefully I'm worrying about nothing but I do think I might have missed an essential part of what you were actually asking. Oops! It won't take long to clear up, relates to where you talked about "distinguishing" additions.]
Hi Phil and welcome to the forum
Thanks for wading through the above and really glad to hear it made some sense. I think most people balk at long detailed posts/threads however it looks like you not only didn't balk but absorbed everything too which is pretty amazing. Don't think I've ever seen a 'second' post like yours so thanks a heap for putting that time in - much appreciated.
Your question is a great one too and really interests me as Section W was a very hard section to add to the BIABacus as it affects every other area so many existing formulas had to be re-written. I think the time spent though was worth it as it means that the BIABacus can actually be used for any form of three-vessel brewing (and extract) and, let's face it, many brewers start out with kettles that are smaller than they like. Another reason why we wrote Section W is that it can't be found in any other software. I know we requested it of some major software but it was too complex. Anyway, we have it now and many other things such as the auto-efficiency versus fixed efficiency of other software.
Oops! Better answer your question - just had my fellow brewer around. We did 3 hours work and then tested beers for about 5 hours
The Logic of Section W
The difference between 'Water Used in a Sparge' and all the other fields in Section W, is that 'Water Used in a Sparge' actually sees/touches the grain. In other words, it rinses the grain.
In full-volume, single vessel brewing (let's call that "pure" BIAB) the mash (soak) and rinse (sparge) are simultaneous as all the water is used in one hit. All that water, of course, "sees" the grain. What we've found over the years (including side by sides and just collecting data), is that it doesn't make any difference whether the grain sees the water in one hit or several - the end result is the same. The 'Dilutions' post above talks on dirty white jeans being soaked in water. The important thing is how much water you soak those jeans in, not the number of stages because, in brewing, we don't have a "spin" function like we do on our clothes washing machines. (That's a real mental hurdle to get over and took me a few years to even prove it to myself because I was educated to thin that a sparge is a rinse and therefore should be just like washing your clothes!).
So, in the BIABacus, any 'Water Used in a Sparge' is treated as water that can clean our grain from sugars. This means that if you add a number beside it, you'll find that none of the estimated efficiency figures in Section P will change.
However, any dilution figure will change Section P because, that water is not being used to clean your grain.
I put a pause there and you'll notice one in Section W of the BIABacus as well because all water that does not see the grain can be effectively regarded as dilutions.
The BIABacus splits those dilutions into three areas; 'Water Added Before the Boil', 'Water Added During the Boil' and 'Water Added to Fermenter' for two reasons. The first but not the most important is that when you add the dilution will affect important numbers such as 'Gravity into Boil', 'Gravity of Ambient Wort' and 'Gravity into Fermenter (usually Original Gravity)'. The second and more important reson is that where you add the dilutions affects the quality of wort and the BIABacus will throw you red warnings if your dilutions are getting out of control.
Two extreme/silly examples are on a standard batch (1.050 OG and 23L/6 Gal Volume into Fermenter):
1. If you added 19L or say 5 Gal before the boil (or any time after) you are going to be cleaning the grain with bugger-all water - you will get unacceptable extraction of sugars from the grain (kettle efficiency) and the BIABacus will tell you so. It will say... RECIPE WON'T WORK!!! (Examine warnings to right carefully.)
2. If you added 11L or say 3 Gal into your fermenter, besides the above, you are going to be "cheapening" your wort. The BIABacus warning in version PR1.3T will say Try to reduce dilution amounts to improve recipe integrity.
I think we might have improved on that warning in later unreleased versions. I hope we have, as that amount of dilution into fermenter is crazy and only just prevents triggering the "RECIPE WON'T WORK!!!" warning.
Phil, I think that's about it
. I'm sure I have either put you to sleep, answered your question or something in between
. I enjoyed myself though
In all seriousness, this stuff can be really confusing and complicated if, like me, you "grew up" with other software/tools. For brewers who have never been exposed to other "static" brewing software and the education that goes with it, the "dynamic" nature of the BIABacus (any change you make affects everything else) makes total sense.
If you have found the above
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