Halving recipe changes properties in BeerSmith Software

[anak85]

Hi there!

I am just experimenting with the BeerSmith software and trying to brew half of the Sierra Nevada Pale Ale this weekend. I entered the full recipe and then proceeded to halve the batch. But the IBUs and the Color are suddenly different. Any idea what is going wrong?

I halved the recipe manually btw. If I half it using the "Scale recipe" function the ingredients are not halved either. They get adjusted to some weird values that suddenly achieve the same IBUs and colouring.

The mash efficiencies and water quantities seem very strange between the two...





Any suggestions? I bought the ingredients for half a batch already.

[Oginme]

Just halving the recipe manually when using the same equipment does not account for losses in your mash tun.  This is why when you used the scale recipe feature, the amounts were not the same as your manual halving of ingredients.  What the program does is increase the mash efficiency in the half batch to draw the same amount of sugars that you should get into the fermenter based upon the brew house efficiency specified in your equipment profile.  It does this regardless of the actual mash efficiency most likely being the same or close to that of your full batch.

When I do scale down a recipe, I start with constructing a new equipment profile to take into account the greater percentage loss due to dead space in the mash tun.  I will reduce the brew house efficiency based upon the difference in % loss.   For example, if I brew 20 liters with a BHE of 80% and a loss to dead space in my mash tun of 2 liters with a boil off of 4 liters, my loss in the mashing process is 2 liters / 24 liters = 8.3% loss.  The same system with 10 liters into the fermenter would be 2 liters of loss in the mash tun, 4 liters of boil off giving a loss in the mashing process of 2 liters / 14 liters = 14.3%.  This difference comes right off of the brew house efficiency in order to maintain the same mash efficiency which is where the sugar is drawn from.

For the IBU, the impact is on the other end of the process.  By using the same equipment profile, you will have the same end of process losses and the same calculation as above applies from post boil to fermenter.  With a greater percentage loss in the post boil volume, the IBU will be lost as well, which is exhibited by the lower IBU number.

[anak85]

Just halving the recipe manually when using the same equipment does not account for losses in your mash tun.  This is why when you used the scale recipe feature, the amounts were not the same as your manual halving of ingredients.  What the program does is increase the mash efficiency in the half batch to draw the same amount of sugars that you should get into the fermenter based upon the brew house efficiency specified in your equipment profile.  It does this regardless of the actual mash efficiency most likely being the same or close to that of your full batch.

When I do scale down a recipe, I start with constructing a new equipment profile to take into account the greater percentage loss due to dead space in the mash tun.  I will reduce the brew house efficiency based upon the difference in % loss.   For example, if I brew 20 liters with a BHE of 80% and a loss to dead space in my mash tun of 2 liters with a boil off of 4 liters, my loss in the mashing process is 2 liters / 24 liters = 8.3% loss.  The same system with 10 liters into the fermenter would be 2 liters of loss in the mash tun, 4 liters of boil off giving a loss in the mashing process of 2 liters / 14 liters = 14.3%.  This difference comes right off of the brew house efficiency in order to maintain the same mash efficiency which is where the sugar is drawn from.

For the IBU, the impact is on the other end of the process.  By using the same equipment profile, you will have the same end of process losses and the same calculation as above applies from post boil to fermenter.  With a greater percentage loss in the post boil volume, the IBU will be lost as well, which is exhibited by the lower IBU number.

Thanks for the indepth answer.

So how do I go about setting my equipment profile correctly? I have a Klarstein Mundschenk 30L system (same as the Brew Monk) and want to brew 10L and 20L batches.

Regards!
Phillip

[Oginme]

Since you are using the same equipment, I would not expect any change in the mash tun loss, so that remains consistent.  I would start by taking your current mash efficiency, change the fermenter volume, and start by adjusting the BHE by the difference in the losses.  i.e. in the first example for mash tun losses, you go from 8.3% loss to 14.3% loss.  If your BHE for a full batch is 75%, knock it down by 14.3 - 8.3 = 6% as a start and then you can modify it after you brew.  This should get you in the ballpark.

[anak85]

Since you are using the same equipment, I would not expect any change in the mash tun loss, so that remains consistent.  I would start by taking your current mash efficiency, change the fermenter volume, and start by adjusting the BHE by the difference in the losses.  i.e. in the first example for mash tun losses, you go from 8.3% loss to 14.3% loss.  If your BHE for a full batch is 75%, knock it down by 14.3 - 8.3 = 6% as a start and then you can modify it after you brew.  This should get you in the ballpark.

I think you lost me a little bit.

Well, since I have no idea what my mash tun loss is, I guess I should just simply record losses during my next brew in all stages and post them for support?

[anak85]

But are there no profiles I can use as an approximation from similar style systems? I understand that it would be good to have precise information but just to prepare my recipes a little better it would be good to be able to import some examples for full size / half size batches.

Right now I am quite unsure what water quantities I should be using this weekend...

[Oginme]

It looks similar to many one vessel system, such as the grainfather.  Most grainfather users that I have talked to have had to do slight changes to their profiles to match the results of their specific devices. 

[anak85]

It looks similar to many one vessel system, such as the grainfather.  Most grainfather users that I have talked to have had to do slight changes to their profiles to match the results of their specific devices.

I just found the button to import profiles. There is a Robobrew which is fairly similar. I will start with that.

What is meant with the full, medium and light bodies during the mash profiles? What is suggested for IPAs and Pale Ales?

[Kevin58]

The temperature at which you mash is what determines a full, medium or light bodied beer.

Mashing at the low end of the conversion scale... around 148-152 F will produce a more conversion of complex starches to sugars giving you, in theory, more fermentation and a clean, lighter tasting beer.

In the middle at 153-156 F is of course where medium bodied beers result.

Mashing higher at 155-158 F will result in less starch conversion leaving a beer with more unfermentables and giving you a full bodied beer.

[Kevin58]

PS. If you find an equipment profile that matches your system you should still do some volume measurements to tailor that profile to your way of brewing. This will give you far better results when using the software. Even if you don't find a profile in the software or in the add-ons section it's not hard to create your own profile. All it takes is filling with water, draining and measuring what is left behind. That's an over-simplified description but its not much harder than that.

Here is a video tutorial of a larger system but the concept is the same...
https://youtu.be/HwEbjOt8OR8

and one more for good measure...
https://youtu.be/QmW7pwQP5mQ

[anak85]

PS. If you find an equipment profile that matches your system you should still do some volume measurements to tailor that profile to your way of brewing. This will give you far better results when using the software. Even if you don't find a profile in the software or in the add-ons section it's not hard to create your own profile. All it takes is filling with water, draining and measuring what is left behind. That's an over-simplified description but its not much harder than that.

Here is a video tutorial of a larger system but the concept is the same...
https://youtu.be/HwEbjOt8OR8

and one more for good measure...
https://youtu.be/QmW7pwQP5mQ

Thanks!

I think I calculated the Brewhouse Efficiency for my full size batch.

I used Vinna Malt (1.035) 11 pounds and Crystal malt 10L (1.036) 1,1 pounds for a 6,07 gallon batch. So the Potential is 71,7.

My actual gravity was around 1.052 so the efficiency is 72,5%. Sounds roughly correct I assume. So you suggest using 66,5% efficency to start for the half batch?

[Oginme]

I think that would be a fairly safe place to make your first half batch recipe.  With the higher water addition for the mashing due to the higher percentage of volume losses, you may see a bit of a bump in efficiency. That will or will not prove itself out in the long run with a couple of brews behind you.  As someone who does predominantly 10 liter batches, I can attest the an improvement in efficiency going from 20 liters down to 10 liters all full volume BIAB.  The nice thing is if you come in with higher gravity readings, you can always choose to let it ride or dilute down and end up with slightly greater than 10 liters at the end.  It is much harder to compensate the other direction (low gravity vs target).

[anak85]

I think that would be a fairly safe place to make your first half batch recipe.  With the higher water addition for the mashing due to the higher percentage of volume losses, you may see a bit of a bump in efficiency. That will or will not prove itself out in the long run with a couple of brews behind you.  As someone who does predominantly 10 liter batches, I can attest the an improvement in efficiency going from 20 liters down to 10 liters all full volume BIAB.  The nice thing is if you come in with higher gravity readings, you can always choose to let it ride or dilute down and end up with slightly greater than 10 liters at the end.  It is much harder to compensate the other direction (low gravity vs target).

Thanks a lot! I might even hold back 0,5-1L Water just to make sure I do not need to do any reducing of the volume after my boil.

Tomorrow is the big day followed by a second brew on Sunday

[Oginme]

Good luck and keep good notes on volumes and gravity throughout the process.  One additional thing that has helped me is not to trust the pre-printed/etched volumes on kettles or containers.  They are not applied by actual measurement but by design and I've been off initially on volumes due to inaccuracies in actual volume versus kettle markings.

[anak85]

Hi there!

I just have a quick question about the BeerSmith software. It says that the estimated pre-boil gravity should be 1.041 SG. But it does not mention at which temperature. I am guessing at the mash temperature otherwise the conversion to 20?C would be 1.068 which is higher than my target gravity of 1.055SG

My last mash temperature is 78?C.