Adapting recipes from Brewfather - am I doing this right?

[muppix]

Morning Campers! I'm planning my next two all grain brews and have run into a bit of a snag, wondered if the Brewfather veterans among you could take a moment to point me in the right direction.

My problem is that at the end of the adaptation process (below) I'm a couple of hundred millilitres over my system's mash volume, and Brewfather has scaled the sparge water down to just 300 ml, which seems too small to even bother with. When I scale the 19 litre batch down to 15 litres in order to avoid hitting the mash volume limit, Brewfather cuts out the sparge step altogether. Eh? The original recipe has 25.6 litres mash water and 5.4 litres sparge, with a total mash volume of 31 litres. I can't use the original recipe as-is for a number of reasons, the main one being that it's built on 60% efficiency which means a 9.4 kg grain bill, and my system tops out at 9 kg.

Anyway, back to that adaptation process, and I want to call out what I'm doing first in case there are any glaring errors. I'm using the Brewfather web app in premium (trial) mode.

1. Find a recipe I like the look of. Right now I'm keeping it simple and avoiding complex fermentation schedules / water treatments, sticking with single infusion mashing and fly sparging, ideally with basic fermentables and affordable hops. I copy the recipe into my own library.
2. Hit the 'brew' icon in order to create a batch with that recipe, so that any changes I make to it are sandboxed to the batch, and I'll always have the unadulterated recipe in my library for reference. If it works out well I can always update my library recipe from the batch recipe.
3. I take a screen-shot of the various values from the reference recipe and keep it up on screen over the following steps:
   
   
   
   
   
4. After checking that I am working on the batch recipe, I swap out the original equipment profile to my own profile (B40pro) which I've previously checked and saved. (going forward I still need to check this profile to make sure that chiller loss, boil-off etc are all in line with my system, but I'm still green and have no reason to doubt whomever created this particular profile) As I change the profile I'm careful to then edit the boil times and target volume back to those found in the original recipe, because those values are overwritten in this step and I may have brewed a different batch size last time around, etc.
5. On saving the profile change all the green sliders go haywire, and I'm prompted if I want to scale the recipe, which makes them return to their reference positions as before.
6. I now start swapping out the ingredients in the recipe for the ingredients that I have access to. For example, the recipe might call for a Simpsons Golden Promise Pale Ale Malt at 5.5 EBC but I have another Golden Promise Pale Ale at 6.0 EBC. When I switch ingredients I always update the vitals, which in turn has an effect on the green sliders that I then compensate for by adjusting the quantities. As I'm doing this I have another window open on my desktop with The Malt Miller / Amazon / whatever where I build my shopping baskets, and a third window where I'm importing those quantities into Brewfather's inventory. I think that's a really neat feature but it does fall down slightly because it can't handle two versions of the same ingredient, e.g. a quantity of Citra at 14% and another at 12.5%. At least not that I've found. I digress ...
7. When I've optimised the recipe by using only ingredients on hand I double check that all the green sliders are in the same positions as they were in the reference recipe. Sometimes that's not possible due to a number of factors, but I figure that I just need to get them as close as I can.
8. Once I'm ready to brew I tick the boxes next to the ingredients to remove them from my inventory, and make no further changes to the batch recipe.

This is where I got to when I ran into problems with the maximum mash volume on my 'optimised' recipe, sticking with 19 litres (fermenter) target and a brewhouse efficiency of 72%:

Now I know that I'm not going to achieve that kind of efficiency this early in my journey, but decreasing the efficiency in the recipe increases the fermentables needed, and at 7.57 kg I don't want to add too much more.

In order to address the things I'm not comfortable with - the low sparge volume and the excessive mash volume - I tried scaling the recipe down to 15 litres from 19, but that cuts out sparging altogether:

What on earth's going on here? Have I picked too big a beer for my B40pro to manage at 19 litres? Sorry for all the detail, I wanted to include all relevant factors. With that, the recipe is a Yeti Imperial Stout and you can find it on Brewfather here. Thanks in advance for any comments or suggestions!

 

[jeg3]

For stronger beers you need more mash water but then you need less sparge water because you want the runnings to be higher gravity.

Try scaling down the batch size.

 

[jeg3]

When I add the GF G30 profile in it limits the mash + grain to the maximum capacity which is 30 litres.

It then adds sparge water to get to your desired batch size. It may not result in the desired OG. And changing to a different equipment profile will alter dead space etc. which changes it again.

I haven't used Brewfather for that long but liked it enough to buy the premium version.

Edit - I noticed your mash efficiency is only 60%, which means you need more grain to achieve the desired OG, which needs more mash water. With a high gravity beer and low mash efficiency the calculator may not call for much or any sparge water because the mash water will provide the full volume.

 

[muppix]

Try scaling down the batch size.

That's exactly what I did, and going from 19 to 18.75 litres cut out the sparge water altogether, but by 15 litres it's back. Weird.

For stronger beers you need more mash water but then you need less sparge water

That makes sense. What I don't get it why the ratio of mash water to sparge water doesn't scale in a linear / predictable fashion.

15 litre batch	18.75 litre batch	22.5 litre batch
Mash Water: 24.39 L Sparge Water: 0.35 L Total Water: 24.74 L Boil Volume: 21.08 L Pre-Boil Gravity: 1.075	Mash Water: 29.62 L Sparge Water: 0.00 L Total Water: 29.62 L Boil Volume: 24.99 L Pre-Boil Gravity: 1.076	Mash Water: 29.34 L Sparge Water: 5.15 L Total Water: 34.49 L Boil Volume: 28.89 L Pre-Boil Gravity: 1.077

 

[jeg3]

It's not linear because the dead space and losses are constant

 

[WonkyDonkey]

That's exactly what I did, and going from 19 to 18.75 litres cut out the sparge water altogether, but by 15 litres it's back. Weird.



That makes sense. What I don't get it why the ratio of mash water to sparge water doesn't scale in a linear / predictable fashion.

15 litre batch	18.75 litre batch	22.5 litre batch
Mash Water: 24.39 L Sparge Water: 0.35 L Total Water: 24.74 L Boil Volume: 21.08 L Pre-Boil Gravity: 1.075	Mash Water: 29.62 L Sparge Water: 0.00 L Total Water: 29.62 L Boil Volume: 24.99 L Pre-Boil Gravity: 1.076	Mash Water: 29.34 L Sparge Water: 5.15 L Total Water: 34.49 L Boil Volume: 28.89 L Pre-Boil Gravity: 1.077

I don't know the B40pro intimately but assume that it operates in a similar way to most of the other All-in-One systems; I have a Robobrew 35l. What you have to take into account with all these systems is that there is a void below the malt pipe that isn't always in contact with the grain but does form part of the overall mash water. To try and give an example of your system, assuming it holds 40 litres max:

Void space = 10ltr

Grain weight = 8kg

Water to grain ratio = 3ltr / kg

Mash water required = 10 + (8*3) = 34ltrs

Now when you factor in the space taken up by the grain, for arguments sake we'll say it is 1ltr / kg, then the total volume in the machine would be 42ltr which is over the capacity of the machine. In order to reduce the volume you can either reduce the batch size (7kg would equate to 10+7+21=38) or decrease the water to grain ratio. A ratio of 2.5ltr / kg for 8kg would come to 10+8+20=38, thus allowing you to do bigger volumes of bigger beers.

As with the Robobrew you will probably be better off setting a min & max volume of mash water to use, that way if you tip over say 30ltr of total mash water then it will add it to the required sparge water. You'll want some headspace else things could get very messy!!

I will say that I don't know your system or your efficiencies but this might give you a start. I'm only on my 20th batch and still tweaking things as I go.

Good luck with it ✌

 

[muppix]

Thanks for the detailed explanation @WonkyDonkey, there's some good points there. I do indeed have some dead space beneath the malt pipe and I think the utilisation of that space depends on the water circulation method; just going around the malt pipe (as Brewtools recommend for the first 20 minutes) isn't going to expose the grain to that water, but once you start circulating up the centre pipe as well you change the utilisation of not only the water beneath the malt pipe, but all of the water in the mash. Of course no equipment profile is going to be able to cover every detail, and if it did there would be an astounding amount of complexity.

Regarding the water to grain ratio, I understand that if you use less mash water for a given volume of grain then that mash water will have a higher gravity at the end, because the goodness from the grain will be less diluted. So reducing that ratio makes sense if it gets you under the limit of your grain + water volume - your mash limit - and you can make up the batch volume to a certain extend by adding sparge water. But the goodness within the malt has to be a finite resource, so there's going to be a point where the sparge water comes out as, well, just water. Maybe that's what they're referring to when they talk about potential yield in malt?

All right, I'm gonna stop there because I have a feeling that several of my questions are going to answer themselves over the next couple of brews, and I don't need to dissect everything ad infinitum now. (read: I need to save some of the forum's good will for when I really need it)