Braumeister 20 Low Mash Efficiency

[Trapdoor]

Hi folks,

For the past 3 or 4 brews I've been experiencing poor mash efficiency (~67% apparently,) with my braumeister 20.

I thought it might be due to approaching the limits of the malt pipe capacity so yesterday I tried to do a 6kg load in a double mash - 2 mashes of 3kg each.
I ran a step mash programme as follows: dough in @ 55C / 30 min rest at 62C / 30 min rest at 64C / 20 min rest at 67C / 15 min rest at 72C (second final mash only).
Beersmith modelled the post-mash OG to be 1.045 and post-boil to be 1.053 (calculated at 70% efficiency,) but I clocked in low at 1.040 post-mash and 1.050 post boil.

I'm buying grains pre-milled from a well known UK source and have tried both fine crush and standard crush with similarly low efficiency results. I think I've got a good handle on my boil off volumes and trub losses, it's just the mashing stage which I am repeatedly missing numbers on. I would like to one day do some bigger beers but without getting my efficiency up that simply wont happen.

Any tips or advice?

 

[foxbat]

If you can rule out the crush and because the BM is a recirculating system with temperature control throughout the mash then I doubt the mash itself is the problem. I'd be looking in the direction of your sparge. Do you do one? If not, save back a few litres from your full volume and trickle it at 75C over your hoisted malt pipe to rinse out the sugars.

 

[Trapdoor]

I've not been sparging recently. I've been following the no sparge method by having the entirety of the grain and malt pipe submerged. People were recommending this method to help with efficiency which is why I started doing it in the first place.

I will try a conventional sparge again on my next brew. Thanks!

 

[QED]

I wouldn't get too hung up about efficiency unless your efficiency is constantly fluctuating. If your efficiency is reasonably consistent at around 67% then go with it. Your beer should be consistent. Don't stress about a few % points. Does your beer taste good?

 

[McMullan]

You don’t seem to be having much luck with your mashes, Trapdoor, do you? I doubt, as your title suggests, it’s anything to do with the BM itself. Mash efficiency for a 20L BM is typically around 78%, in my experience. Optimal grain crush for a BM is about 1.2mm. Best to mill it yourself so you know it really is about 1.2mm. Mashing is all about enzyme-catalysed reactions. Important factors to control include temperature, pH and time. Maybe check the BM temp probe reading with a reliable thermometer. Check mash pH and reconsider/consider how you treat your water, if necessary. In the mean time, simply increasing the time of your mash is going to increase your mash efficiency, unless you’ve really got something terribly wrong somewhere in the process. Note with full-volume mashes efficiency is likely to drop a little so I'd add a little more grain to compensate. Start with about 10% more. Good luck!

 

[Trapdoor]

Does your beer taste good?

Invariably yes it does taste nice, although I am probably not going to win any awards from BJCP judges. :)

 

[Trapdoor]

Optimal grain crush for a BM is about 1.2mm. Best to mill it yourself so you know it really is about 1.2mm.

Maybe check the BM temp probe reading with a reliable thermometer.

Check mash pH and reconsider/consider how you treat your water, if necessary.

I am not controlling these three things at all currently. I'm London so i know the water is pretty darn hard but I haven't been testing pH or doing anything to it other than half a campden tab.

Maybe it's worth getting a pH meter, thermometer and grain mill to start controlling these factor.

 

[QED]

@Trapdoor If you're brewing with London water, maybe also consider a water test. Something like the below. Also, if you search for your local water authority you should be able to download a report with a lot of the details you'd need to plug into a water calculator (but not all)

https://www.brewuk.co.uk/water-analysis.html

 

[PhilBrew]

Hi Trapdoor

Beersmith modelled the post-mash OG to be 1.045 and post-boil to be 1.053 (calculated at 70% efficiency,) but I clocked in low at 1.040 post-mash and 1.050 post boil.

... sorry, if the answer to this question is "of course", but it's easy to spend a LOT of time worrying about non-problems if you don't check the facts ... if you're looking to compare efficiencies, you need to state volumes and gravities ... can I just check that you are comparing like with like there ... the volume of wort that Beersmith modelled at 1.045 at end of mash was the volume in the BM when you measured that 1.040 figure? Similarly, the volume of wort that Beersmith modelled would be in the BM at end of boil, at 1.053, was actually there at end of boil, at 1.050?

Cheers, PhilB

 

[Trapdoor]

if you're looking to compare efficiencies, you need to state volumes and gravities ...

I think there is probably a degree of error in the volumes since I dont have a very accurate way of measuring volumes within the braumeister but it looks pretty close judging by the tick marks. I ended up with almost exactly 5gal into the fermenter after trub loss etc. which is my target. For sure though there is a significant uncertainty in volume measurements. Any advice on the best way to accurately measure volumes in these kinds of systems?

Regardless of volumes I'd like to increase my efficiency if possible simply because then I have the option to produce either more volume or more importantly higher gravity.

 

[Andrew Elliott]

Might be worth checking your pH. I brew with pretty hard water and invariably have to acidify irrespective of what I brew.

 

[PhilBrew]

Any advice on the best way to accurately measure volumes in these kinds of systems?

... Dipstick!! ... it's not often you get to advise someone and insult them both at the same time ... a 50cm stainless steel rule won't cost you much and you can calibrate it by adding a "known" ltr (whether measured in a "reliable jug", or weighed on "reliable" scales) of water in your empty BM and measure, and repeating until the additional measures start become regular ... draw yourself a graph of depth to volume

Regardless of volumes I'd like to increase my efficiency if possible

... yes, but you'll be better informed at how to tackle that if you know where the losses are occurring ... if you're getting poor mash-efficiency in the first place, then the suggestions about grain crush, mash duration and pH/water treatment will be the best place to start ... if your mash efficiency is good but pre-boil efficiency is much lower, then you're losing a lot of volume/sugars soaked up in grain, and maybe reviewing your no-sparge/sparge prodedures would be the best way to address that ... and if you're getting OK efficiencies all the way until end of boil, but losing LOTS in transfers/trub, then maybe whirlpooling and more effective pickups will be your next thing to try

Cheers, PhilB

 

[foxy]

Hi folks,

For the past 3 or 4 brews I've been experiencing poor mash efficiency (~67% apparently,) with my braumeister 20.

I thought it might be due to approaching the limits of the malt pipe capacity so yesterday I tried to do a 6kg load in a double mash - 2 mashes of 3kg each.
I ran a step mash programme as follows: dough in @ 55C / 30 min rest at 62C / 30 min rest at 64C / 20 min rest at 67C / 15 min rest at 72C (second final mash only).
Beersmith modelled the post-mash OG to be 1.045 and post-boil to be 1.053 (calculated at 70% efficiency,) but I clocked in low at 1.040 post-mash and 1.050 post boil.

I'm buying grains pre-milled from a well known UK source and have tried both fine crush and standard crush with similarly low efficiency results. I think I've got a good handle on my boil off volumes and trub losses, it's just the mashing stage which I am repeatedly missing numbers on. I would like to one day do some bigger beers but without getting my efficiency up that simply wont happen.

Any tips or advice?

Forget about faffing around with step mashes just do a simple infusion mash, there is no need for a step mash unless you are using an under modified pilsner malt.
It would be a good idea to alter the water profile, I am lucky have a soft water with a poofteenth of bugger all salt/acid additions needed.
You have accurate markings on your tie bar, work out the water volume from those measure off the boss and easily work out the liters per centimetre.
Have you entered into BeerSmith that you are doing full volume mash/no sparge?
I don't know where you read you will get a better efficiency with full volume it should have read efficiency will suffer, though you will get a better beer.
67% isn't bad for no sparge, if you want to raise it to 70% just add a bit more base malt.
Getting the most out of the BM as in water to grain this modification helps.

 

[Edison]

I have a 20l BM too and recently started doing no sparge just to cut down on time and simplify the process. I was getting bogged down with details before but am now enjoying brew days with a more relaxed approach.

I've got pretty close to the numbers today, just two points off my post boil OG. I've been doing a 10 min @ 40c to rehydrate the grains, 60 min @ 63c and 10 min @ 78c with FWH and 30 min boil.

Try adding 3-5ml 80% lactic acid to bring your mash ph down closer to 5.2.

We have South Staffs water here and it's pretty hard, so if I'm doing anything pale I usually fill up the BM overnight from a cheap RO filter and use Beer Smith to calculate salt additions for the mash.

All the best, hope this helps!