My efficiency sucks

[BrewHark]

I am totally perplexed. I’ve been all-grain brewing for a few years and have experimented with different set-ups, techniques, etc. and still cannot hit my efficiency targets. My beer otherwise turns out very good, but I have to tweak the recipes to account for poor efficiency and that bugs me.
Over this past weekend, I did an IPA that was at 64% and an Amber Lager that was at 68% (mash efficiency). For the IPA, I did a single infusion mash (after doughing in) at 152⁰ for 1 hour. For the Amber Lager: 125⁰ steadily increasing to 140⁰ over 25 minutes, then increased to 158⁰ over 15 minutes and held it between 156⁰ - 158⁰ for the next 40 minutes. I apply direct fire to the mash tun. I don’t mash out.

Other pertinent information: My crusher is set at .05, which is just a little tighter than the factory setting (should I go tighter?). My mash tun is a 10 gal stainless steel vessel with a screen bottom. The screen is a couple inches off the bottom which creates 2 gals of dead space. I fill the bottom of the tun with two gals of water and pre-heat as I am preparing the grist. After adding the grain (and salts), I dough-in a gallon at a time until I reach my target ratio (qts/lbs). For the IPA, I did a thicker mash of 1.2 and for the Amber Lager, 1.45 (note: this does not include the two gallons I add to the bottom of the tun to account for dead space). I stir frequently throughout the mash and recirculate with a pitcher by draining the hotter wort off the bottom of the tun to the top to maintain my target temps.

In both cases, I sparged with 4 gallons of water (165&#8304. I use a circular gravity sparge arm and try to keep the water about an inch above the grain bed. I also stir during the sparge. I generally aim to get about 6.5 gals to the pot. Because of the dead space, I use about 10 gals of water with each brew. After I’ve filled my pot, I usually end up draining a gallon or more from the mash tun into the sink. This is usually a pretty clear run, until I tip the tun to drain the stuff that is below the outlet (usually pretty thick with grain that made it through the screen).

One other note: I usually start with purified water and add salts, as I am on a well. I keep my calculated ph between 5.2 and 5.4 and target specific water profiles using the EZ Water Calculator 2.0.
Any thoughts on what I should be doing differently?

 

[duboman]

Because your mash efficiency is quite low I would look at crush first. .05 seems kind of big, my mill is set to .037mm.

Second, 2 gallons of loss is quite a bit and it seems like you are leaving a lot of wort behind full of sugars that aren't being accounted for in your process.

My set up with the mill and about a pint of loss yields me a consistent 80% total brew house and mash/lauter efficiency across the board.

You can also look at your sparge to be sure you are not getting channeling of the grain bed.

Are you hitting your volumes both pre and post boil? How are you taking your gravity readings and are you adjusting for temperatures?

 

[BrewHark]

I am hitting my volumes post boil and I adjust for temps. I will try tightening the crusher, but in the past when I had my LBS crush it for me, I had similar problems.

The grain bed is not channeling, because I stir during the sparge.

Maybe I scrap the false bottom and go with a screen hose or some other jerry-rigged manifold?

 

[ph0ngwh0ng]

I don't fly sparge, but from what I could understand about the process, stirring the mash while fly sparging is a no-no, since you want the water to trickle through your grain bed to extract sugars.

 

[chickypad]

I would still think crush, LHBS's often have theirs set pretty coarse so I wouldn't necessarily go by that. Post a pic next time you brew. Next, I agree with duboman seems like you're wasting a lot of concentrated wort in your deadspace. My set up is similar to yours with 2 gallons below the false bottom so I have a diptube. Also, how fast are you sparging? I never stir when fly sparging, does that cloud up the wort when you do it?
If none of this helps at least it sounds at least like your numbers are fairly consistent. If it's just a matter of throwing in an extra lb of grain or so doesn't sound like the end of the world.

 

[peterj]

I think it's definitely the 2 extra gallons of water that you're adding. I don't think you can just ignore that water in your mash ratios either. All of that water is still coming into contact with your grains and it also has sugar in it. So you're just diluting everything with 2 gallons of water and leaving behind a lot of the sugar in your mash tun.

2 gallons of dead space seems like A LOT to me. I usually have about 1/2 - 1 quart of dead space, but I batch sparge with a SS braided hose. I usually get around 77-80% effeciency.

 

[BrewHark]

peterj : That's what I'm afraid of. With a 12# grain bill, I will use 4 gals of water, in addition to the 2 gals I fill my tun to get to the false bottom. To get 6.5 gals to the kettle with nothing left in the tun and after accounting for absorption, I would only be able to sparge with about 3 gals of water. That doesn't seem like enough. So I have been sparging with 4-5 gals of water and pitching some of the wort. I am going to try the dip tube as the poster above suggested, but that still doesn't help with the dead space issue. I hate to lose the false bottom because it works like a charm (and wasn't cheap!). I'm flummoxed.

 

[disney7]

I would try decreasing your mill gap to around 0.030 and double crushing. The second pass through the mill doesn't hurt the hulls any further and separates the endosperm from them. If you are crushing at 0.050 I'll bet you have a lot of endosperm that is stuck in the hull and even quite a few uncrushed kernels.

Also, one thing you didn't mention is how long your sparge takes. If you are sparging too fast that would cause a problem for sure. If you are collecting a little over six gallons, your sparge should take about 45 minutes to an hour.

 

[duboman]

Definitely install a dip tube, you'll leave a lot less wort behind

Also tighten the gap on your mill and stop stirring your mash during the fly sparge. Also be sure the sparge is taking 45-60 minutes, anything less is too fast

 

[BrewHark]

Thanks guys - My sparge usually takes about 25-30 mins, so that could be the problem. Guess I need to open the valve to "trickle" and see what happens.

I will also add the dip tube and tighten the crush. Hopefully that will take care of it.

 

[day_trippr]

10-4 on never, ever stirring the mash once a fly sparge begins. It totally defeats the whole point of fly sparging, and ends up being an inefficient batch sparge.

I'd be interested in knowing what grain mill comes with a recommended gap setting of .050". That right there is definitely the beginning - and likely largest contributor thereto - of the efficiency problem...

Cheers!

 

[peterj]

peterj : That's what I'm afraid of. With a 12# grain bill, I will use 4 gals of water, in addition to the 2 gals I fill my tun to get to the false bottom. To get 6.5 gals to the kettle with nothing left in the tun and after accounting for absorption, I would only be able to sparge with about 3 gals of water. That doesn't seem like enough. So I have been sparging with 4-5 gals of water and pitching some of the wort. I am going to try the dip tube as the poster above suggested, but that still doesn't help with the dead space issue. I hate to lose the false bottom because it works like a charm (and wasn't cheap!). I'm flummoxed.

Yeah I would think a dip tube should do the trick. That should decrease your deadspace so you won't be leaving as much behind.

Now when you say you're pitching some of the wort, what do you mean? Like you're pitching out wort that you drained out? The wort that you drain out first is the most concentrated, and it becomes less and less concentrated as you continue to sparge. If you're pitching out some of your first runnings so you can fit more second runnings (or sparge runnings I guess? Sorry I batch sparge.), you're choosing less concentrated wort over more concentrated which is also bad for effeciency. You should sparge until you hit your pre-boil volume and then stop, no matter how much sparge water you used. This will leave the least concentrated wort behind in the dead space.

 

[beersk]

My vote is to tighten the gap on your mill. .05" is pretty wide. I have mine set to .032", but wouldn't go any tighter than that. I still only get around 75%. As long as it's consistent, I don't care about how high it is.

 

[joelrapp]

I would say your issue is 3 fold.

First off I would consider a redesign w/ 2 gallons of dead space.

Second would be your grain crush. I run my grain through at .032" then do a second pass and tighten it up just a bit. I run about a 92% mash efficiency and 82% brewhouse efficiency.

Third I would never stir your mash during the sparge. Let it settle and clear, run it slow.

You will likely see a large jump by removing the dead space, then another substantial increase from a more fine crush and yet even more by not stirring.

 

[pdxal]

Tighten your mill gap, then decrease that 2 gallons of dead space. Don't chuck wort, too, concentrate it with your boil.