Author Topic: Grainfather Settings in BeerSmith for 2.5 Gallon Batches  (Read 2868 times)

Offline Supa

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Grainfather Settings in BeerSmith for 2.5 Gallon Batches
« on: July 20, 2018, 09:45:10 AM »
Does anyone know the best way to update the Grainfather equipment profile for a half-batch? My last few 2.5 gallon batches have not come out the way BeerSmith predicted and the most obvious reason is that I am not scaling the equipment the right way.

I would like to either gain a better understanding of how to set up a 2.5 gallon equipment profile for the Grainfather --or-- gain insight into how to use BeerSmith's Scale feature to properly scale down a 5 gallon batch.

Here is my Grainfather equipment profile for a 5 gallon batch for reference.

[NOTE: HBT user, Oginme, responded stating that my efficiency would change with a smaller batch to 67.1%. This may be a good adjustment. Ideally, I can get some help from BeerSmith users on additional adjustments so the software's predictions will more closely mirror my results with smaller batches]




« Last Edit: July 20, 2018, 09:47:03 AM by Supa »

Offline Oginme

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Re: Grainfather Settings in BeerSmith for 2.5 Gallon Batches
« Reply #1 on: July 23, 2018, 06:21:44 AM »
OK, I've given enough time for someone to pop in here to reply further, so let me elaborate more on my recommendation:

With the smaller batch size, you are not changing your equipment.  Given this, your process settings for losses will most probably remain the same as with the larger batch. 

You may experience a bit more boil off, since the Grainfather will be heating less fluid, but I am guessing that since it is a temperature controlled system, that it will be pretty close to the same evaporation rate with the element regulating the boil temperature.  With the geometry of the vessel remaining the same, so that should not factor too strongly in the rate.  You may see some initial condensation on the upper part of the vessel, but this should normalize pretty quickly after reaching a boil.

With the losses being fixed combined with the smaller batch size, you will have a change in your water to grain ratio which should result in a higher mash efficiency, but how much will be hard to figure until you actually make a brew and measure volumes and gravity through out your process.  If this is the case, you will see a slightly higher gravity from your pre-boil wort which you can adjust either by adding water or adjusting your boil time if you so choose.  If you are within a few gravity points, and I suspect that you will be, I'd let it go and brew away.

So, the only real significant change will be the percentage of post-boil wort which is lost when draining the device.  Given the added percentage of wort you can basically ratio the brew house efficiency to come close to where it will fall:  basically 67% from your 75% normal efficiency for a full 5 gallon batch. 

As I do not own a grainfather, there may be something that I might be missing that would have a further impact on process losses or boil off.  Given that, what I do know from past experience in brewing and other industries indicates that this adjustment should get you close enough for the first brew that any adjustments for future brews can be made fairly easily.
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Offline Supa

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Re: Grainfather Settings in BeerSmith for 2.5 Gallon Batches
« Reply #2 on: July 23, 2018, 07:42:53 AM »
Thanks for your insight!

I have actually come in significantly under my OG target the last time (and first time) I tried to do a 2.5 gallon batch with the Grainfather. That said, I also got a new grain mill, so there is a chance that my crush wasn't fine enough. A 5 gallon batch of stout under shot BeerSmith's OG by about 25 points too, which is why I think it may be crush-related.

I will adjust the efficiency of the system for a half-batch, adjust my rollers and give it another shot!

 

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