Extremely low brewhouse efficiency - BE Mash & Boil

[jerrylotto]

I don't usually check pH (colorblindness and all).

Purchasing inexpensive pH meter. Color blindness shouldn't come into the equation if you're measuring with a meter and colormetric methods rarely have enough accuracy for anything meaningful.

 

[dwightr8]

Are you sure your volumes are right? The marks in the kettle can be off by quite a bit. See this thread: Mash and Boil *actual* boil volume ?
I've got a Digiboil and I know mine are off a bit. I always fill from gallon jugs which I have calibrated by weight. 1 gal of water weighs 8.33 lbs at room temp (70F). I'm sure this isn't your whole problem but it could be a contributing factor.

 

[hendenburg2]

May not be necessary if you are getting a good evenly distributed flow over the grain bed. Grainfather uses a perforated top plate with center overflow pipe and a valve for flow control. You couldn’t stir theirs if you wanted to. Without that setup I think a pump could cause uneven channeling of wort thru the grain unless you moved the outflow around manually. if I added a pump to my M&B, I’d still stir and it would just replace the vorlauf. Trick would be adjusting flow to keep from pumping the unit dry under the sleeve. Might need rice hulls to improve down flow depending on the mash.
My best results with the M&B were with grain bills 12 lbs or less. Largest was 14 and it was work.

With recirculation setup, I make sure that the top of the grain in the sleeve is *slightly* submerged, so in theory the wort is being evenly distributed. Tomorrow is my brew day, so I'll attach pictures.

 

[hendenburg2]

Are you sure your volumes are right? The marks in the kettle can be off by quite a bit. See this thread: Mash and Boil *actual* boil volume ?
I've got a Digiboil and I know mine are off a bit. I always fill from gallon jugs which I have calibrated by weight. 1 gal of water weighs 8.33 lbs at room temp (70F). I'm sure this isn't your whole problem but it could be a contributing factor.

The only place where the M&B determines my volumes is after sparging. I buy water in 1 & 2.5 gallon containers, and my electric kettle has volume markings in liters. My 5 and 6 gallon brew kettles also have volume markings on them.

 

[Alex4mula]

I bet your main problem is in the crush. I mash thin at 1.6 and crush my grains. Conversion is 89 to 99%. Brew house high 70s. Need to squeeze grains at end of sparge. You will get there. Go search the M&B forum for tips.

 

[hendenburg2]

Hey all. Brew day first update:

Here's the grain bill I'm using today:
8 lbs US 2-row
1lb 3 oz C20
6 oz black malt
4 oz Munich II
3 oz US chocolate

Strike water volume: 3.5 gal
Strike water temp: 162F
Mash temp: 156F
Mash out temp: 168F
Total mash time: 95 minutes
Pre-sparge gravity: 1.08

Setup pic:

 

[hendenburg2]

Update 2:

Sparge is done.

Pre-boil volume: 6.5 gallons
Pre-boil gravity: 1.04

Target final volume: 5.25 gallons
Estimated post-boil OG: 1.05
Estimated BH efficiency: 73%

 

[Coastalbrew]

Hope you enjoy your brew day!

Curious if you actually hit your target mash temp with that strike temp? My M&B has about a 15* drop (on a 5G batch) from strike temp to mash temp when I add the grains. So if I want a mash temp of 156* I need a strike temp of 171*.

Cheers!

 

[hendenburg2]

My M&B only dropped about 8F. From 162 to 154, but this batch only had 10lbs of grain.

However, here's the real reason I suspect for the lower temp drop:
The M&B's temp sensor is right at the bottom, close to the heating element. This would mean that it's not measuring the bulk volume of the strike water, just the very bottom of it. However, I ran the recirculation pump while heating my strike water. This meant that my strike water was at a more uniform temperature.

Also, I did notice that my temp sensor reads a bit off - wort starts boiling at 215F (I'm at sea level)

 

[Alex4mula]

Hope you enjoy your brew day!

Curious if you actually hit your target mash temp with that strike temp? My M&B has about a 15* drop (on a 5G batch) from strike temp to mash temp when I add the grains. So if I want a mash temp of 156* I need a strike temp of 171*.

Cheers!

Grain temp also has to do on this. My basement where grains are is at 63-64°F all year round. I set the M&B to 160° and my strike water gets to 166°F. After pouring grains, they end up around 152°F all the time. But I mash thin at 1.6 so maybe that has some impact too. Once the user gets to know all these variables your process will get more predictable. It takes some time.

 

[Jako]

pH certainly does correlate with efficiency, especially if the pH is too high. This can happen if your water has high residual alkalinity and your grain bill includes mostly pale malts. Have you brewed any dark beers, and if so, did they do a little better in terms of gravity? The 5.2 product is largely viewed as bogus, BTW, but let's not go there since it seems unrelated.

I am grasping at straws a bit, as you've been brewing for 10 years (!) and using the same water for a long time. So really the question goes back to you: What is different with your Mash & Boil process vs. the all-grain system you used before that? (Which I assume got you better efficiency?)

I would try a very simple, small batch (1-2.5 gallons) with the same exact crush and water, without the M&B, and see how you perform. Remove variables from the mix so you can rule things out.

i have had issues like this. i built a new system and started using RO water at the same time. for me it was water and lack of boil off.

 

[Dancy]

May not be necessary if you are getting a good evenly distributed flow over the grain bed. Grainfather uses a perforated top plate with center overflow pipe and a valve for flow control. You couldn’t stir theirs if you wanted to. Without that setup I think a pump could cause uneven channeling of wort thru the grain unless you moved the outflow around manually. if I added a pump to my M&B, I’d still stir and it would just replace the vorlauf. Trick would be adjusting flow to keep from pumping the unit dry under the sleeve. Might need rice hulls to improve down flow depending on the mash.
My best results with the M&B were with grain bills 12 lbs or less. Largest was 14 and it was work.

I just brewed my 2nd batch on my new M&B with pump, a 4.25
G batch of Belgian Dark Strong Ale with 14 lbs. While it required some work as you said, my flow was much improved over my first batch with 10 lbs of grain because (I think) of the 1/2 lb of rice hulls I used. Also, I stirred pretty frequently.

 

[SFC Rudy]

My issue with my Mash & Boil (and all other one vessels systems) is heating and storing sparge water. I was also getting low efficiency.

My fix is I stopped using the M&B instructions; I put John Palmers calculations into an excel spreadsheet. also bought a second M&B. I mash in one and drain until I get half my boil volume then I sparge in the second (heated to 170). I use a pump (https://www.amazon.com/gp/product/B01G305PK0/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1) to recirculate until the sparge water "changes color". Let sit 10 minutes or so then drain until I get half my boil volume then combine the two runnings into the "sparge" M&B and drive on. I have been getting between 85% and 90% efficiencies doing it this way.