The Grain Father
Mangrove Jacks new all grain unit - its nice
Replies to This Discussion
-
Permalink Reply by Cain Harland on
-
Beer tools pro is pretty good but if I hadn't paid for it already and got used to useing it I would probably go brewtoad. Theres a lot to be said for having stuff online and being able to pull up the recipe you made on your desktop on your phone or tablet during brew day. Good for sharing recipes too.
-
Permalink Reply by Peter Smith on
-
you can do the same with beersmith but you have to buy the $9 app, in my book its not the tool you choose its that you accept you need a tool....
-
-
Permalink Reply by David M on
-
GrainFather BeerSmith profile and approach
Looked at BeerSmith’s logic and tested it against the values I used and measured on 2 GF brews at the weekend - managed to come up with a profile and method that fits close enough for the moment.
This is a work in progress and I am pretty green when it comes to brewing so would appreciate anyone else’s comments and modifications.
Apologies for the long post. Thought I would explain as well as state.
A problem with BeerSmith is it doesn’t seem to handle single vessel brewing very well. It supports BIAB methods but these don’t use fly sparging or rims recirculation.
This profile is based on the following assumptions from the details in the GF manual.
Pre boil qty for 60 min boil is 28L at 100C to result in 23L at 20C temp in the fermenter. Calculated as – 23L in fermenter, 2L lost to boil, 1L Cooling & Shrinkage, 2L lost to trub & dead space in GF below pump inlet.
Grain Father equipment profile:
Brewhouse Efficiency: 75%, Hop Utilization: 100%
Mash Tun Vol: 30L, Mash Tun Weight: 4kg, Specific heat: 0.12, Lauter Tun deadspace: 0
Top up water:0, Boil time: 60mins, Boil off: 2L per hour, Cooling Shrinkage 4%
Loss to trub and chiller: 2L, Batch volume: 23L, Fermenter loss 1.5L
The GF has 3.5L dead space below the pipe (measured and confirmed) which is why 3.5L is added to mash water. GF recommend a 2.7L per kg mash water ratio and unless someone has a good reason I intend to stick to this.
I set the dead space for the mash lauter tun to 0 in BS as otherwise it messes up the calc for sparge water. It adds the dead space twice – once for mashing and once for sparging.
You need to calculate the intial strike water using the GF provided formula – (Grain weight (kg) x 2.7) + 3.5 (dead space) and enter this in the mash in step in the mash profile.
I also had to change the Grain absorption value under Tools:Options:Advanced to 0.8 – the figure GF recommend as otherwise sparge calcs are out. BS recommends 0.96. Do any more experienced brewers have any comments on this value and its implications?
Mash profile:
When creating a recipe I use the temperature - 1 step mash profile - select the one with the body you want but this just presets the mash temps which I override based on the recipe anyway.
I edit the stages
Mash In - type: temperature, Step temp: your mash temp, step time: your mash time, rise time - I set at 3-5 mins which gives the water enough time to come back up to temp when the grain is added, Water to add: I set this based on the water calculated using the GF formula, water grain ratio is auto calc based on water to add so ignore it.
Mash Out – type: temperature, step temp: 75.6, step time: 10, Rise time: 8-10 mins (about the time it takes mine to go from mash to mash out temps), water to add: 0.
The correct sparge water should now be calculated by BS on the mash page
It is .4-.5L greater than the GF calc. I think SB factors in something else but it is close enough for me.
Now everything works fine for me. Did a 60 min and a 90 min boil and the calcs it gave me were close enough.
-
Permalink Reply by Dene McDonald on
-
Nice work David. You should send this to the grainfather people to put in their FAQs
-
-
Thanks for this... just wanting to clarify...
assumptions from the details in the GF manual... 2L lost to trub & dead space in GF below pump inlet.
Then...
The GF has 3.5L dead space below the pipe (measured and confirmed) which is why 3.5L is added to mash water.
These are two different measures right? By "below the pipe", you mean kettle space below the grain pipe right?
-
-
Yes your correct
The 3.5L refers to the space below the grain pipe. It explains the 3.5L added to the mash water calc.
The 2L is the space below the pump inlet which is deadspace volume you can't transfer to the fermenter
Apologies if my descriptions caused any confusion.
-
-
Help needed calculating GF efficiency
So the Grainfather is my first AG kit (previously have been doing mini mashes in pots on gas) and I've been trying to accurately calculate efficiency but the MJ formula gave me a ridiculous figure in the 90s and a more thorough calculation using John Palmer's approach and typical malt yields gives me a figure of 85% - still quite a bit higher than the 75% people are posting here so I'd like to check if/where I might be going wrong?
I measured my pre-boil SG at too high a temp (71˚C) but calculated a hydrometer temp correction using this online calc to arrive at est.1059 @ 20˚C calibrated. I was brewing the Chur Pale Ale kit which came with the early adopter package. Here's the other vitals:
Pre-boil volume: 29L (7.66 US Gal)
Grain Bill: 6.3Kg (13.89 US lb). 77% Weyermann Pale Ale Malt (2-row pale ale malt)
Strike water: 20.5L (5.4 US Gal)
Mash time: 75 mins @ 67˚C
Mash out: 10 mins @ 75˚C
Sparge water: 12.5L (3.3 US Gal)
I calculated a max yield gravity for all grains in the grain bill as follows:
Weyermann Pale Ale - 38PPG x 11 lb / 7.66 US Gal = 54.6
Weyermann Pale Wheat Malt - 37PPG x 1.16 lb / 7.66 US Gal = 5.6
Weyermann Munich II - 35PPG x 1.16 lb / 7.66 US Gal = 5.3
Weyermann Carahell (Caramel 10) - 35PPG x 0.66 lb / 7.66 US Gal = 3.0
Total max yield: 68.5
My extraction was 59 so...
=> 59/68.5 = 86%
Too good to be true? It's a decent sized grain bill and a relatively longer mash time so seems plausible.
-
Permalink Reply by mattd2 on
-
I think the mistake is coming from adjusting the SG from 71°C - from my understanding correcting temps over approx. 38°C should be avoided (since they are not accurate). Given that you are estimating that the preboil SG is above the post boil SG by 5 points has me reasonably confident this is the case (otherwise after about 4 litres of boil off your SG into the fermenter would be approx. 1.068)
Did you take an OG reading of the wort going into the fermenter? And how much you were left with in the pot after the boil?
-
-
Yeah that does seem like the cause of trouble. The SG I actually measured was around 1040 @ 75˚C (the hydrometer calc correction didn't take input above 71˚C). I took the calc's max value of 1059 but it must have been a lot higher because my OG reading (@ 24˚C) was 1065 - 11 points over the recipes target. I think there were issues with that reading too as I took the test sample through the fermenter tap and it was full of trub so that can't have helped - you live and learn!
I estimate I lost around 6 litres during the 90min boil (29 - (20.5 + 2.5)) so if that OG reading of 1065 was accurate, that'd place the pre-boil SG somewhere around 1050.
Going to be interested to see what the FG is on this batch...
I later realised I should have added about 4.5 liters of water to bring it down to target OG (or added some boiled water ramping up to boil) - you live and learn.
-
-
Looks alright based on your assumption of 2.5L left in the kettle and 20.5L into the fermenter (= 23L post boil in the kettle). Base on you initial numbers you had the potential to extract (7.66 * 68.5 = ) 525 points. so that would give you:
Brew house extraction and efficiency, in the kettle as per the original definition, (65 * 23 / 3.785 = ) 395 point and (395 / 525 = ) 75% eff
Brew house extraction and efficiency, in the fermenter as per the Beersmith definition, (65 * 20.5 / 3.785 = ) 352 point and (352 / 525 = ) 67% eff
So about what Grainfather was estimating
-
Permalink Reply by Sam DT on
-
What was your OG & volume into fermenter?
From the above it looks (to me) like you're calculating your mash efficiency not your brew house / total efficiency, i.e. using both pre-boil volume and gravity.
I assume you'll lose some volume due to dead space & hot & cold break when you transfer to your fermenter (maybe a couple of liters?). That might just get you down to the high - mid 70's?
-
-
Thanks yeah - I had the two a bit confused. That calculation is the mash efficiency - so it looks like 86% is in the ball park. I didn't record the volume in the kettle after flame-out but 20.5l made it into the fermenter. I'd say 2.5-3 litres was lost to dead space and break material.
All in all I just need to be a bit more diligent with the numbers and temps I read at on the next batch. Would also have been helpful if the grain kit that came with GF listed a target pre-boil SG.
Help Fund This Site
FRESH LIQUID YEAST!!!
DIRECT FROM THE LAB
Luke's Beer+
Events
© 2024 Created by nzbrewer.
Powered by
