BM mods to address the OG limitation.

Did you pimp your Braumeister? Show us your mods!

BM mods to address the OG limitation.

Unread postby joostdb » Tue Feb 25, 2014 9:11 pm

We all know about the OG limitations of the BM for brewing big beers. The simple workarounds include double mashing and extremely long boils to evaporate and concentrate wort (which reduces batch size considerably). I am looking into ways to follow the standard brewing procedure (single mash, ~90min max boil) to get high OG beers via tweaking the design slightly.

The reason why the BM design is limited in terms of post mash/pre-boil OG is because of 1) the way water flows upward through the malt tube requiring it to be full and 2) it the large amount of water in the system which is not in direct contact with the grist. In traditional brewing systems 1) water drips down through the grain bed and 2) there is only the false bottom which can be designed to take up almost negligible space, and then the piping that circulates the wort through the heating system and back to the top of the grain bed- also negligible in volume. So almost 100% of the water is in contact with grain.

Addressing point 1) may be possible however would require a pretty major redesign of the system. You *might* be able to reverse the flow of the pumps, route the wort upwards around the malt pipe via tubing and sprinkle it over the grain bed in the malt pipe. Easier to do on the 50L, you could unplug the outer heating element (relying only on the element underneath the malt pipe for heating, assuming it can keep the wort at 60-70c) and attach the pipes directly to the pump outlets. On 20L also possible but you would need enough water around the malt pipe to keep the heating elements immersed so they do not scorch the wort.

Addressing point 2) maybe be easier via slight tweaks. With the BM design there are two areas that take up a significant amount of space with no grist contact; the bottom section of the malt pipe (underneath the mesh), and the space outside of the malt pipe which needs to be filled with water to a certain level to ensure the heating elements are immersed.

I had the following ideas to minimise these dead space areas:

- Unplug the outer heating element during mashing, utilising only the inner element (works on 50L only). This will allow you to use around 3L less water, as you do not need to worry about the outer heating elements overheating - only need to ensure enough water so the pumps do not run dry. Question becomes whether the inner element has enough heat output to keep the wort at 60-70C during mashing. May be easier on 20L batches with 50L BM using the 20L malt pipe as there is less water to heat.

- Reduce the height of the space underneath the lower mesh in the malt pipe (remove a few cm from the bottle of the malt pipe) to minimise the dead space. The challenge here is to ensure the water continues to flow uniformly upwards throughout the grain bed, so you may need to add diverters on the pump outlets to ensure this (alternatively you could just untighten and rotate the malt pipe several times during the mash to ensure uniform flow).

Has anything thought about any of this, tried any of the above, or do any other type of mods?
joostdb
 
Posts: 18
Joined: Tue Feb 25, 2014 3:31 pm
Location: Belgium
Model: 50 litres

RE: BM mods to address the OG limitation.

Unread postby BrauTim » Tue Feb 25, 2014 11:42 pm

I have thought about some of this and have done some reading related to the subject. As you point out, limitations are down to design, it depends how high you need to go, up to around 1.070 seems fine from the grain and then sugar additions can get you heading towards 1.100

As for workarounds - well these are traditional brewing methods, the old ways of making high strength beers of 1.100 and above (probably before the 1st World War and modern industrialisation made it possible to mash larger quantities of grain) was to use multiple runnings from a single mash and then boil each running individually to increase the SG, then re-combine the runnings and boil as normal with hops. Or they made multiple beers of different strengths from the multiple runnings.

joostdb wrote: 2) it the large amount of water in the system which is not in direct contact with the grist. In traditional brewing systems 1) water drips down through the grain bed and 2) there is only the false bottom which can be designed to take up almost negligible space, and then the piping that circulates the wort through the heating system and back to the top of the grain bed- also negligible in volume. So almost 100% of the water is in contact with grain.

Addressing point 2) maybe be easier via slight tweaks. With the BM design there are two areas that take up a significant amount of space with no grist contact; the bottom section of the malt pipe (underneath the mesh), and the space outside of the malt pipe which needs to be filled with water to a certain level to ensure the heating elements are immersed.


I'm not sure this is correct or a limitation to making high strength beers, in the BM the wort is constantly circulated and filtered through the mash bed so all the wort does come into contact with the grain and all the enzymes within the liquid comes into contact with the starch in the grain providing enough chemical reaction for conversion. Recent studies I have read show that the water/grist ratio does not have as much of an effect on conversion as say the wort pH (information buried in these references somewhere Effects of Mashing and The Theory of Mashing from memory the information did not take into account recirculating systems).

I have mashed with 27 litres and 35 litres, it made no difference to the conversion and strength of the wort!

The difference between the BM and a HERMS or RIMS system is that the wort is pushed up through the grain rather then allowed to flow down through the grain under gravity, in both systems the whole of the wort comes into contact with the grain allowing for chemical reactions, I don't see a difference, there is no dead space in either system that could cause a restriction to conversion.

I don't have an answer to making bigger beers from a single mash & boil schedule other than by increasing the amount of grain and that is where the BM restriction lies, just as it does with any mashtun size, there is only a certain amount of grain you can squeeze in there.

One possibility that would work with the 50BM would be to have an intermediate malt pipe size, say 30 litres, you could then mash with probably around 40 litres and 9/10Kg of grain, or in my case I could brew around 30 or 36 litres of ordinary strength beer, enough to fit a 30L keg or two cornies which to me seems a more sensible brew length than 23/18/20/50 litres for a homebrew scale.

Maybe someone enterprising or Spiedel themselves could take this on :)

If it's high ABV that's needed, then the mash schedule could be manipulated to favour beta-amylase and a highly attenuative yeast could bring the SG down low, depends on the beer style I suppose.
Last edited by BrauTim on Wed Feb 26, 2014 12:15 am, edited 1 time in total.
To brew or not to brew, that would be a stupid question !
User avatar
BrauTim
 
Posts: 519
Joined: Sun Feb 02, 2014 1:03 pm
Location: England
Model: 50 litres

RE: BM mods to address the OG limitation.

Unread postby fy0d0r » Wed Feb 26, 2014 7:38 am

There is a DYI MOD described at HBT thread on BM (BTW, I hate TLAs :D )

It involves drilling some holes in a long pipe (that can be shut by some washers and bolts if not required), by doing that you can use long pipe for ~30L brews or put more malt than in the short pipe).
fy0d0r
 
Posts: 85
Joined: Mon Feb 10, 2014 1:10 pm
Location: Moscow, Russia
Model: 50 litres

RE: BM mods to address the OG limitation.

Unread postby niels » Wed Feb 26, 2014 8:45 am

fy0d0r wrote:It involves drilling some holes in a long pipe (that can be shut by some washers and bolts if not required), by doing that you can use long pipe for ~30L brews or put more malt than in the short pipe).

This sounds similar to a modification done by someone on the Dutch Hobbybrouwen.nl forum. He drilled 4 holes in the malt pipe (20l) and put a rubber band around it to cover them up when he wants to use the full size of the malt pipe.

malt_pipe_01.jpg
malt_pipe_02.jpg

The rubber band is made by cutting the bottom out of a cake pan:

cake_pan.jpg
cake_pan.jpg (7.97 KiB) Viewed 6545 times

Niels
User avatar
niels
Site Admin
 
Posts: 1054
Joined: Mon Dec 02, 2013 8:08 pm
Location: Belgium
Model: 50 litres

RE: BM mods to address the OG limitation.

Unread postby BrauTim » Wed Feb 26, 2014 9:33 am

What an enterprising lot us Braumeisters are, we need to recruit these brewers and get them to post in the modification section

:cool:
To brew or not to brew, that would be a stupid question !
User avatar
BrauTim
 
Posts: 519
Joined: Sun Feb 02, 2014 1:03 pm
Location: England
Model: 50 litres

RE: BM mods to address the OG limitation.

Unread postby joostdb » Wed Feb 26, 2014 10:00 am

Thanks for the replies. I was aware of the intermediate malt pipe mods via holes or otherwise however I always assumed that people were doing this to generate a larger volume of medium OG wort which could be boiled down to high OG wort and leave a decent batch size after all the evaporation.

BrauTim wrote:Recent studies I have read show that the water/grist ratio does not have as much of an effect on conversion as say the wort pH (information buried in these references somewhere Effects of Mashing and The Theory of Mashing from memory the information did not take into account recirculating systems).

I have mashed with 27 litres and 35 litres, it made no difference to the conversion and strength of the wort!.


What I am reading here however is that the ratio of grain to water does not play a role on the conversion efficiency and strength of the wort. I agree that there is not much influence on the efficiency (this will be between 75%-85% depending on the malt type used), however I cannot imagine that it does not play a role on the strength (aka gravity) of the wort.

1 Kg of grains has a certain sugar content that can be dissolved in the wort. If you mash this with 1L of water, or 10L of water, the amount of dissolved sugar stays the same, so the 10L batch will have 1/10 the gravity as the 1L batch. You cannot just magically generate an extra 9 Kg worth of sugar content and have the 1L and 10L batches at the same gravity...

BrauTim wrote:I have mashed with 27 litres and 35 litres, it made no difference to the conversion and strength of the wort!.


This goes against the above logic - assuming the same about of grain was used in both cases. I would be interested to know how you would explain this (I remain open minded).

As all my BM mod suggestions were based on this premonition let's clarify this before continuing with mod ideas....
Last edited by joostdb on Wed Feb 26, 2014 10:02 am, edited 1 time in total.
joostdb
 
Posts: 18
Joined: Tue Feb 25, 2014 3:31 pm
Location: Belgium
Model: 50 litres

RE: BM mods to address the OG limitation.

Unread postby martinj » Wed Feb 26, 2014 12:47 pm

Last weekend I pushed mine 20 L to produce 15L of OG 1.092 wort on a 90 min boil with any addition of sugar or other extracts.
This shows we could go pretty far without any modifications with just giving it some love ;)

For reference a mashed with ~ 20 L using 6.27kg of malt, lautered with ~5 L.
Paused during mash and stirred 4 times.
martinj
 
Posts: 5
Joined: Tue Feb 04, 2014 7:38 am
Location: Sweden
Model: 20 litres

RE: BM mods to address the OG limitation.

Unread postby joostdb » Wed Feb 26, 2014 1:45 pm

martinj wrote:Last weekend I pushed mine 20 L to produce 15L of OG 1.092 wort on a 90 min boil with any addition of sugar or other extracts.
This shows we could go pretty far without any modifications with just giving it some love ;)

For reference a mashed with ~ 20 L using 6.27kg of malt, lautered with ~5 L.
Paused during mash and stirred 4 times.


Impressive. Best I have been able to do (on 50L with 20L malt pipe) is use 5.75Kg of malt (absolute max that will fit for me), 27L of water (minimum needed to ensure coils covered) and 5L of sparge water which resulted in pre boil OG of 1.052 and after a 90 min boil OG of 1.072. These are nowhere near the numbers you are getting.

I'm surprised you can get away with only 20L (without scorching heating coils) and use a whopping 6.27Kg of malts. No wonder you are getting such a high OG figure. Perhaps the 20L BM is less OG limited than doing a 20L batch on the 50L?

(This would also prove the grain to water ratio gravity principle in the post above.)

What I will do is measure up the volume inside the malt pipe (above mesh), underneath the malt pipe mesh and around the malt pipe (to keep heating elements covered) on both the 20L and 50L (with both short and long malt pipes) and see what the water to grist ratio's come out as. As the mods suggested aim at reducing these area's of 'dead space' (not in direct contact with grist - even though the water circulates through the system) I can make an approximation of how much more the gravity can be increased in the design.
Last edited by joostdb on Wed Feb 26, 2014 1:46 pm, edited 1 time in total.
joostdb
 
Posts: 18
Joined: Tue Feb 25, 2014 3:31 pm
Location: Belgium
Model: 50 litres

RE: BM mods to address the OG limitation.

Unread postby Twonky » Wed Feb 26, 2014 6:30 pm

A while back there was a 50l BM with 70l conversion for sale on a dutch second hand site... so curious as I was I mailed with the owner to get to know what the conversion entailed. And this is what the dude had done. He had created a filter plate with "legs" that would rest just above the heating coils, used an external pump to draw of the wort through the tap, and then let it flow back on top of the grain thus circulating the wrong way, but being able to utilize the full volume of his 50l BM.... drawback is having to empty the BM before being able to boil...

It didn't sound like something that I wanted to but who knows, if you really want versatility then....

Something else I have been thinking about, and have not yet tried, so initially I was planning on holding off until I tried it, but here goes.....

I read that 1kg of pilsner barley could convert up to 10kg of adjuncts.
What if you would crush 1kg of pilsner, and mix with 4kg of wheat flower, and then put that in a 10l bucket and single step mash at 67C this is easy jsut cover the bucket with sleeping bag and leave it (this is the way I started out brewing ;-)
I as thinking of using a BIAB bag in this bucket for easily removing the mash...

Then brew as normal, and after removing the malt pipe add extra wort to the boil.
I used a brewing calculator and it seems like a good opportunity to add extra mash volume without any destructive procedures.

What do you guys think?
Cheers
:cheers:
Twonky
 
Posts: 92
Joined: Sat Feb 15, 2014 10:41 am
Location: Almere, Nederlad
Model: 50 litres

RE: BM mods to address the OG limitation.

Unread postby joostdb » Wed Feb 26, 2014 10:15 pm

I have found mention of the relationship between water/grist ratio (aka mash thickness) and gravity: http://braukaiser.com/wiki/index.php?title=Understanding_Efficiency#Measuring_conversion_efficiency

first_wort_gravity.gif

In my case with the BM 50L and 20L malt tube, I can fit in 5.75Kg of grains, volume inside malt pipe = 16.84L, vol inside malt pipe under mesh = 9.62L, vol around malt pipe (8cm in height to cover heating elements) = 2.54L, totalling 29L, minus the displacement of the grains (around 2L) bringing me to around 27L of water. This gives a mash thickness of 4.7L/Kg which is pretty close to the 1.052 I got (chart is based on 80% efficiency, I am probably closer to 75% and hence why it is a bit higher in the table).

Removing the unused space around the malt pipe would increase this to 4.25L/Kg, removing space underneath mesh (completely) 3.02L/Kg, and removing both areas would increase to 2.58L/Kg. These give great OG values, and these are pre-boil, after a 60 or 90 min boil these will be high enough for almost all beer styles.

I expect with the mods you would be able to get in the 3.5L/Kg range, perhaps more with the 50L malt pipe or the 20L BM as the ratio of the unused space to the filled grain volume would be lower in these setups.
joostdb
 
Posts: 18
Joined: Tue Feb 25, 2014 3:31 pm
Location: Belgium
Model: 50 litres

RE: BM mods to address the OG limitation.

Unread postby BrauTim » Wed Feb 26, 2014 11:41 pm

joostdb wrote:
BrauTim wrote:I have mashed with 27 litres and 35 litres, it made no difference to the conversion and strength of the wort!.


This goes against the above logic - assuming the same about of grain was used in both cases. I would be interested to know how you would explain this (I remain open minded).

As all my BM mod suggestions were based on this premonition let's clarify this before continuing with mod ideas....


Thinking back to these brews, I must have made SG readings at pre-boil volume (aiming for 31L) which would have been following a sparge in the case of the 27L mash and no sparge in the case of the 35L mash, therefore you can safely ignore my comment about the strength of the wort :)
To brew or not to brew, that would be a stupid question !
User avatar
BrauTim
 
Posts: 519
Joined: Sun Feb 02, 2014 1:03 pm
Location: England
Model: 50 litres

RE: BM mods to address the OG limitation.

Unread postby Lgkex » Thu Feb 27, 2014 10:27 am

I think the fixed rode in the middle of the kettle is an issue to doing double mashes. A good mod would be to make it so that you could unscrew the rod from the kettle. This way you could take the rod out and do BIAB using the malt pipe and the bottom screen. Do single infusion mash in manual mode and don't use the pump, just stir the mash. Split your grain into two runnings. Fill the grain bag with first mash. Mash, remove bag, sparse if you want. Add second bag, mash, and sparse to get volume. Some what wasteful but allows you to do higher gravity beers with all grain.

Other plus with taking the rode out is you can use hop spider in the boil. It would also be easier to whirlpool.
Lgkex
 
Posts: 14
Joined: Fri Jan 31, 2014 10:49 am
Location: Baltimore, MD
Model: 20 litres

RE: BM mods to address the OG limitation.

Unread postby martinj » Thu Feb 27, 2014 1:00 pm

What about a custom BIAB bag that would work with the rod?
You would be able to fit a hefty amount of malt, maybe it would even work running the pumps ?
martinj
 
Posts: 5
Joined: Tue Feb 04, 2014 7:38 am
Location: Sweden
Model: 20 litres

RE: BM mods to address the OG limitation.

Unread postby joostdb » Thu Feb 27, 2014 2:38 pm

Double mashing... not what I was going for :).

But, what would be the difference between the BIAB methods described, and simply using the malt pipe as the "bag" (lift out entire malt pipe, empty out malts, and go for mash round two with a freshly filled malt pipe)? I guess I don't get what value the bags are adding...
joostdb
 
Posts: 18
Joined: Tue Feb 25, 2014 3:31 pm
Location: Belgium
Model: 50 litres

RE: BM mods to address the OG limitation.

Unread postby martinj » Thu Feb 27, 2014 2:58 pm

A bag would puts the constraint on how large the kettle is instead of the malt pipe.
You could use a lot more malt with a bag then using the malt pipe.
martinj
 
Posts: 5
Joined: Tue Feb 04, 2014 7:38 am
Location: Sweden
Model: 20 litres

Next

Return to Modifications

Who is online

Users browsing this forum: No registered users and 1 guest