Author Topic: KISS: Simple All-Grain Brewing Math  (Read 906 times)

Offline denny

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Re: KISS: Simple All-Grain Brewing Math
« Reply #15 on: December 17, 2021, 09:24:25 am »
Sorry, but I don’t see anything particularly simple about all that!😆
But that’s fine, when it comes to brewing, I’ve always been a big believer in finding what works for you and sticking to it.
I use the Brewer’s Friend Recipe Calculator to formulate recipes.  I used OG/FG results on a few early brews and worked backwards to figure out what kind of “Brewhouse Efficiency” percentage I was getting.  I was regularly 70-75%.  So when I use BF to come up with a recipe, if I use 75% BHE, I’m going to come within a point or two of what I’m shooting for with the recipe. And even when I occasionally miss the mark by a little bit more, the beer that results is still pretty much what I want it to be.
That’s as in-depth as I feel the need to get when it comes to efficiency.  Works for me!

Well said
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Offline Wilbur

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Re: KISS: Simple All-Grain Brewing Math
« Reply #16 on: December 17, 2021, 02:37:11 pm »
I don't know exactly specifically how Beersmith works, but my understanding is all brewing software uses PPG in some fashion. In Brewfather it calculates yield relating to extract of sugar. If you want PPG, you take that yield and multiply by 46. Whether you look at %sugar or PPG, it's the same.

I've done the whole hand calculation thing and while it's not very hard I don't see how internalizing it is going to make me a better brewer. I understand how the software works, and if I get a new malt and can find a certificate of analysis then know enough to get an idea of how it should perform. My time is valuable, and I'd rather spend it finishing Garshols book.

Offline tommymorris

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KISS: Simple All-Grain Brewing Math
« Reply #17 on: December 17, 2021, 04:47:11 pm »
I have used the math in Palmer’s How to Brew to build a spreadsheet and I have done that same math by hand many times to validate the spreadsheet.

I also own BeerSmith. Getting BeerSmith to make calculations that seem intuitively obvious once you know the math from Palmer is not easy. I recently changed to a new brewhouse. When I did so I updated my spreadsheet, used the Grainfather app, the Brewfather app, and BeerSmith for several batches. Don’t ask me why. I am a nerd and it was fun.  Grainfather, Brewfather, and my spreadsheet were all lockstep on volumes of water (mash and sparge) needed based on my observed boil off and absorption rate for my brewhouse. BeerSmith never matched those three and never came close. I finally found an approximation by inputing incorrect absorption numbers. It was very frustrating because I had just paid for a one year license for BeerSmith.

BeerSmith does use PPG for each grain. So do Brewfather and Grainfather. I think that is one of Mark’s complaints. The user gets a false sense of accuracy when using a specific PPG for each grain when the math is really not that accurate.

My issue is volumes. I want a tool that is readable on my phone for 50 year old eyes (Brewfather is not) and predicts the right mash and sparge water values to get exactly 3 gallons wort after boil. I’ve got BeerSmith doing that now but I hold my nose because the absorption number I use seems way to low: 0.416 fl oz/oz.  Also, don’t get me started on the unit: fl oz/oz. Why? The  customary unit for absorption rate is qts/lb or gallons/lb. I almost have to break out my Chemistry I text book to convert those units!
« Last Edit: December 17, 2021, 05:30:48 pm by tommymorris »