Bulldog brewer water calculations

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Bentbarrel
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Bulldog brewer water calculations

Post by Bentbarrel » Thu Jul 20, 2017 10:00 pm

Hello all,

I've done a couple of brews with my bulldog and find it very easy to use! However I'm finding that I'm not hitting the OG. I've been using the grainfather calculations for mash and sparge volumes, when re-circing and sparging I leave the sparge plate well above the malt and let it drip down. When re-circing I have a steady trickle going onto the plate but I keep reading about how other users suffer from the wort going into the overflow?

Can anyone point me in the right direction?

Thanks!

Fil
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Location: Cowley, Oxford

Re: Bulldog brewer water calculations

Post by Fil » Thu Jul 20, 2017 11:23 pm

i assume your hitting your volume targets as you dont mention being off there too?

my #1 tip would be..
Ensure you have a good mix/mash in making sure every grain is saturated, and dont be shy applying positive pressure when encapsulating the grain in the malt tube/basket, the idea being to present a consistently solid grain mass(but not too solid it sticks..) that the recirculated liquor will trickle down all over. leave voids and or dry patches and your more likely to get the liquor running through a single path/route and not rinsing the whole grain mass.

an iodine test is simply dropping iodine onto some post mash grain on a white plate, and if the red/brown iodine goes pitch black its indicating starch that was not successfully converted indicating your mash wasnt very efficient and would have benefited from a longer mash and re circulation..

the other aspect to look at is the age of your grain the enzymes dont last forever once its been crushed.

hope thats helpful.
ist update for months n months..
Fermnting: not a lot..
Conditioning: nowt
Maturing: Challenger smash, and a kit lager
Drinking: dry one minikeg left in the store
Coming Soon Lots planned for the near future nowt for the immediate :(

Fil
Telling imaginary friend stories
Posts: 5229
Joined: Sun Oct 16, 2011 1:49 pm
Location: Cowley, Oxford

Re: Bulldog brewer water calculations

Post by Fil » Thu Jul 20, 2017 11:24 pm

ps welcome to Jims
ist update for months n months..
Fermnting: not a lot..
Conditioning: nowt
Maturing: Challenger smash, and a kit lager
Drinking: dry one minikeg left in the store
Coming Soon Lots planned for the near future nowt for the immediate :(

Bentbarrel
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Posts: 5
Joined: Mon Dec 21, 2015 2:08 pm

Re: Bulldog brewer water calculations

Post by Bentbarrel » Fri Jul 21, 2017 7:48 am

Thanks very much FIL, I've got a mosiac smash to do later so will try your suggestion out.

Dave S
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Re: Bulldog brewer water calculations

Post by Dave S » Fri Jul 21, 2017 10:59 am

Also, if you are using GF calculations as you say, the Sparge Water calculation is wrong. They are using a water retention factor of 0.8, i.e. water retained by the grain = grain weight x 0.8. I have never heard of anyone apart from GF using this figure. In my experience it has always been 1 or 1.1. I know that if I use 0.8 I will be at least 2-2.5L short on my brew length at the end. The loss due to hops and trub is also wrong IMO. I find it more like 2.5L rather than the 2L they specify, though this will change anyway depending on how much hops/malt there is in the wort. In any case you will also need to adjust that figure to suit your own system.
Best wishes

Dave

RobP

Re: Bulldog brewer water calculations

Post by RobP » Fri Jul 21, 2017 2:22 pm

Assuming the mash fully converted (as above), and assuming you haven't an unrealistic expectation for brewhouse efficiency, the biggest reason for undershooting the right OG is not sparging enough.

Dave S
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Re: Bulldog brewer water calculations

Post by Dave S » Sat Jul 22, 2017 9:50 am

RobP wrote:Assuming the mash fully converted (as above), and assuming you haven't an unrealistic expectation for brewhouse efficiency, the biggest reason for undershooting the right OG is not sparging enough.
Yes that's another issue with the GF. They say the malt basket will hold up to 9kg of grain. Well it will, but you won't hit your numbers with much above 6kg unless you sparge into 2 boilers or one (much) bigger one or parti-gyle. Otherwise the GF boiler volume will not allow you to sparge sufficiently. You need about 7-7.5 L of water per kg of grain to extract the maximum sugars, so with 9kg grain you will need about 63 - 67.5 L of water. Subtract about 10L for grain retention and you get 53 - 57.5 L pre-boil. This will obviously take a considerable time to boil down to 25L.
Best wishes

Dave

Midlife
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Re: Bulldog brewer water calculations

Post by Midlife » Sun Jul 30, 2017 8:25 am

RobP wrote:Assuming the mash fully converted (as above), and assuming you haven't an unrealistic expectation for brewhouse efficiency, the biggest reason for undershooting the right OG is not sparging enough.
Yes I have experienced that, I think I rushed my past brew and sparged to quickly and my OG was lower. All my other brews have exceeded OG target.

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