Starting Volume - mash on 20lt Speidel Bruameister

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Dan Pratt

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Does anyone know what the minimum starting volume of water for 5kg of grain would be to run a 20lt BM?

That is without exposing the elements.
23 is what book says I think? Not sure I always go 25-27
Not sure, but you could just start with say 15L in manual mode with the element off, then top up a liter at a time so you know for next time.

Then just programm your schedule and start. You can have the malt pipe with grain in and all and start your cycle from the start, no problems at all.

Alternatively, add a short rest at mash in temp to your schedule and add your water then.
I have a 9 liter urn that I use for sparging that i can use to add water at the desired temp.

lets go with adding 15lts, get to mash in temp, which for me is 40c, grain goes in, switch pump on and then add water(at same temp) to cover the element.

When I brew under normal use, start volume will be at 25-27 and the wort is only about 3-4 inches below the malt pipe wall once the pump gets going>>> so I'm thinking/hoping that the mash volume will be around 18litres minimum.

Has anyone tried this out?
ok so i tried for minimum volume last week.

i started with 16 litres at 38c and added 5kg of malt which actually required about 2 more litres into the malt pipe to mash in..... started the pump as i had it set for a 10mins @ 40c just to get the volume right. well that volume required another 3.5 litres to comfortably cover the element by about an inch.

so basically the second line on the post is the minimum volume. ended up sparging about 10 litres.

side note - tried MHB advice>>> basic way to get another 3 litres out. put a 2 x 4 timber block under the rear leg before the chill or after the whirpool and it gets a nice angle and more of the volume. cheers.
I've never gone for minimum volume (can't really see the point of it) but went for maximum once. 28 L and got all kinds of problems, circulation was bad and when I lifted the malt pipe the grain was sucked into the wort somehow. So I aleays go for 26L ie the top mark on the rod + 6 L to rinse. Gives me 89% ME most of the times and 22 L into the FV + 1.5 L for Speise.
DeGarre said:
I've never gone for minimum volume (can't really see the point of it)
Minimum liquid volume to maximum grain: for high/er gravity wort?
That takes more time and wastes more energy.
Hi Edak,

I could just boil longer but im trying to get the highest OG from no more than 5.3kg of grain. Currently my max OG is 1055 using MO with 5.1kg and 20 litrs into the fermenter after a 90 min boil.

I could add more grain ( max 7kg so i have read ) to but im aware this in turn puts more pressure on the pump and some stirring may be required, the brau is designed to be left to run without manually doing stuff during the mash.

DOing this less water to grain ration attempt was in search of being able to make a bigger beer. I would have to reduce my fermenting volume to about 15 litres to increase that. Truth is my average ABV from 5kg of grain is arond 5.7% but when making bigger hopped beers this needs to be around 7.5% in order to balance the IBU range of 60 - 100 :)
Hey Pratty,

You wont get 7kg into the 20L model. 5.2kg will be about it.

For big beers I chuck max grain and minimum water in with a 90-120 min boil and cube in a 15L cube. Works a treat.
With the wood under the back leg thing, wouldn't gravity pull all of the break/hop material towards the front and settle it right by your tap? Even a whirlpool won't overpower gravity, would it?

I would have thought to do the whirlpool with something under the front so that the crap settles at the rear of the vessel, drain as much as you can, then slowly remove the wood from the front and THEN put it under the rear and continue draining the clear stuff before the muck, which has predominantly settled at the back, catches up.

I am doing a brew on my system today and will try the method I have just mentioned to see how it goes...

Back on topic though, to improve efficiency of extract you want a higher water/grain ratio during the mash. Mashing in with a low ratio reduces your mash efficiency, so isn't it counter productive to use less to get more from your grain?

I will put more water than necessary in before the mash to improve efficiency (grain/water ratio), if an overflow looks like it is going to happen while mashing in then I will let some of the strike water out, but of course keeping track of how much... I then sparge with the amount of water necessary to bring up my volume to estimated PBV. If I have sparged extra (because if my runnings are looking high I will) and have too higher volume, my system allows me to adjust the boil-time up until my first addition. This allows me to boil longer if my efficiency is too high; or boil less if my efficiency is low.

Granted my colour might change (a little) from a longer boil, but the beer will be closer to the recipe if I can adjust my boil time.
Bongchitis said:
Hey Pratty,

You wont get 7kg into the 20L model. 5.2kg will be about it
without looking at my notes i'm pretty sure that i had 6.9kg in there before, surprisingly without issues.
Yeah last few brews I have done have had 5.75kg and easily looked like it could handle more
I've fit a bit over 6kg in mine, but the circulation is slower and I seem to get lower efficiency, which negates the point of the extra grain (to some extent - ymmv).

I think around 5kg is the sweet spot, go with that much, and if you want higher gravity, mash in with less water, boil longer, add extract to the boil, or do a double mash.

Also, keep in mind that if you have more than 26L at the start of the boil, the elements don't have enough grunt to boil it as vigourously as usual, so your boil-off volume is lower, degreasing your OG as well.

I had a reasonably disasterous run where I used about 6kg of grain, which lowered efficiency, then I sparged more than usual (to rinse the extra grain), so I started with too much volume, so the boil-off wasn't as high as expected. I couldn't boil longer once I figured this out, because it would have screwed up all my hop additions, so I added a bit of dex and still missed my OG.

Does anyone know what the minimum mash volume is with 5kg of grain?
HowlingDog said:
My plan for bigger beers is add DME toget increased gravity.
I think that this would work, but I am still trying to keep it out. I guess that if your PBG was low then you could add a little towards the end of the boil.
Florian said:
without looking at my notes i'm pretty sure that i had 6.9kg in there before, surprisingly without issues.
Shit eh! I max out at 5.2kg in terms of pumps ability to cascade over the malt pipe. I guess i could get 7kg but my BM would not pump.

Do you guys mill your grain specifically. Condition etc?
The most I have had is 5.4kg and that was no worries to pump. I get the lhbs to mill the all the grain the 1.4mm which is considered best for a BM. Going to try for a 6kg and see how ou goes, likely to mash for longer to see that all the malt gets plenty of time at those rests.
I might take your advice on the mill setting Pratty.

Does anyone know what the best way is to set a mill for 1.4mm?

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