First AG Batch, Terrible Effeciency

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hightechlofi

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Location
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I just performed my first all grain mash and my effeciency is terrible. I am brewing an Oscar Blues G'Knight (Gordon) ale clone. I collected 5 gallons of wort. My grain bill is as follows:

Malt Qty(lbs) Potential Calc PPM
US Pale 2 Row 14 1.036 100.8
CaraMunich 1.4 1.033 9.2
Munich 1.05 1.037 7.7
Caramel 30 1.05 1.035 7.3

Preboil OG:

Effeciency: 34/125 = 27%

I am using a sanke mlt with 1"armaflex all around (including top and bottom) with a false bottom and a dip tube.

Here are the mash details:
1) Preheated my mash tun w 2 gal boiling water, poured out before dough-in
2) Added grist to mlt.
3) Added 6.5 gal strike water (1.5qt/lb) at 160f.
4) Stirred to ensure no clumps.
5) Mash temp measured. Untested temp gauge on sanke showed 140f, digital thermometer showed 152f. Assumed digital was correct, future readings are taken with it.
6) Checked temp 30min into mash, 151f.
7) Begin lauter after 60min. Recirculated four pitchers. Runoff never really clear, but no chunks.
8) While draining first runnings, took gravity sample, 1.052 (cooled wort first)
9) Added 3.5gal sparge water (batch sparge) at 180f.
10) recirculated, measured gravity at 1.025.
11) Final Preboil OG: 1.034

So, now the obvious question, wtf did I do wrong? I have two speculations, but as an AG newbie, they are kinda shots in the dark. 1) mash temp was really 140, should have stuck with the sanke gauge, and/or 2) sac conversion was not completed at 60 minutes, needed longer mash. Also, figured out my dip tube is too low and resulted in the low amount of wort collected.

Any help would be greatly appreciated. Gonna top off my og with DME, but need to get this figured out. I tried to give you all of the data, if you need more info, please let me know.

Btw, will this batch even be drinkable, or am I just SOL?

Thanks!!!

PS: Thought I would do a go big or go home beer for my first AG, turns out I am a cocky idiot. Think I am gonna stick with some simple SMaSH brews till I get dialed in.
 
You did everything right. Who cracked the grain? How was the crush? Did you check and adjust your ph? Calibrate that thermometer in the sanke to get better readings. I don't batch sparge so I'm not sure if sparging slow will increase gravity, it really helps with fly sparging. What was you estimated Gravity you where shooting for?

Sorry, kinda all over the place on that but just trying to get ideas as to what you can do.
 
You did everything right. Who cracked the grain? How was the crush? Did you check and adjust your ph? Calibrate that thermometer in the sanke to get better readings. I don't batch sparge so I'm not sure if sparging slow will increase gravity, it really helps with fly sparging. What was you estimated Gravity you where shooting for?

Sorry, kinda all over the place on that but just trying to get ideas as to what you can do.

It was crushed at my lhbs, defalco's in houston. As this is my first ag batch, not sure how the crush was, I just assumed it was good. As for ph, I looked and the only strips I had were lower ph for wine, so just went blind. I used ozarka spring water. I had asked the guy at defalcos and he told me he had used it straight (no adjustment) and it was fine. I will definitely be checking my temp gauge, though. I am kinda embarrassed to say what I was shooting for, but the post-boil og was supposed to come in around 1.080, so I am way off. I had 2.1 lbs dme lying around, so I tossed that in. Boiling right now, so I will see what the post boil og turns out to be.

Would the ph or mineral content make that big of a difference? If so, I may start building my mash water from scratch using ro water and salts.

Thanks for the quick reply.
 
Also, doing a 90min boil to increase OG. How will this effect my hops/ibu's? I have added 1oz northern brewer as first wort hops, my only other addition is at 7min left with 3oz columbus. With the lower OG, is this going to be crazy hoppy? Not that I mind crazy hoppy...
 
With that water and grain bill you pH should have been fine, at least not enough off to explain such horrible efficiency. Something else must be really wrong. Interested to hear what the calibration of the thermometers shows, I'd think you would have to be really off like 10-15 degrees or so. Same with crush, that would have to be pretty darn poor. I don't see anything obvious in your process although not sure what you mean your dip tube was too low - do you mean too high and you left a lot of wort in deadspace?
 
I cut the end of the tube flat, so the weight of the grain pushed it against the bottom of the keg and wort couldn't flow through. I had to use a spoon to pry it up. Was barely a trickle so I got impatient after 5 gallons and left the rest behind.

I cut the bottom up the keg out and use it upside down. I think I am going to replumb it to drain through the 2" opening on the bottom and not even worry about a dip tube.

This was just a side not, not really anything to do with efficiency.

I am going to calibrate my thermometers today, I will post the results.

Could you tell anything about the crush if I posted a picture of the spent grains?
 
Here is a picture of some of the spent grain:



image-2086012245.jpg


Not a close-up, but here is a pic for the grain in the bag:


image-2129073551.jpg


After reading this: http://www.brewersfriend.com/2009/03/28/best-grind-setting-for-grains/ , looks like the crush was too coarse? Could this have been a part of it?
 
did you stir the batch sparge? I'm not an expert but the crush doesn't look horrible to me (I had a bad crush, ended up at 55%, looked way more whole than that), maybe you had a channeling issue? with a batch sparge, that's unlikely though.
 
Yeah, when I added my sparge water I stirred thoroughly, then allowed the grain bed to set for 10 minutes before begining vourlaf/drain.
 
I think the only way you can get 27% efficiency is with a really poor, or non-existent, crush. Or your mash temperature was way off. The other details such as pH, stirring/non-stirring, temperature off by a few degrees, sparging speed, etc. will just account for small, if any, differences in efficiency. A few things in your methodology stood out as "odd" but probably aren't an issue. You indicate that you collected 5 gallons of wort, was that into the fermenter? What was your pre-boil gravity? You also indicated that you measured a "pre-boil OG" but OG is usually taken of the wort into the fermenter, what was the gravity and volume of the wort going into the ferementer?
 
hightechlofi said:
I just performed my first all grain mash and my effeciency is terrible. I am brewing an Oscar Blues G'Knight (Gordon) ale clone. I collected 5 gallons of wort. My grain bill is as follows:

Malt Qty(lbs) Potential Calc PPM
US Pale 2 Row 14 1.036 100.8
CaraMunich 1.4 1.033 9.2
Munich 1.05 1.037 7.7
Caramel 30 1.05 1.035 7.3

Preboil OG:

Effeciency: 34/125 = 27%

I am using a sanke mlt with 1"armaflex all around (including top and bottom) with a false bottom and a dip tube.

Here are the mash details:
1) Preheated my mash tun w 2 gal boiling water, poured out before dough-in
2) Added grist to mlt.
3) Added 6.5 gal strike water (1.5qt/lb) at 160f.
4) Stirred to ensure no clumps.
5) Mash temp measured. Untested temp gauge on sanke showed 140f, digital thermometer showed 152f. Assumed digital was correct, future readings are taken with it.
6) Checked temp 30min into mash, 151f.
7) Begin lauter after 60min. Recirculated four pitchers. Runoff never really clear, but no chunks.
8) While draining first runnings, took gravity sample, 1.052 (cooled wort first)
9) Added 3.5gal sparge water (batch sparge) at 180f.
10) recirculated, measured gravity at 1.025.
11) Final Preboil OG: 1.034

So, now the obvious question, wtf did I do wrong? I have two speculations, but as an AG newbie, they are kinda shots in the dark. 1) mash temp was really 140, should have stuck with the sanke gauge, and/or 2) sac conversion was not completed at 60 minutes, needed longer mash. Also, figured out my dip tube is too low and resulted in the low amount of wort collected.

Any help would be greatly appreciated. Gonna top off my og with DME, but need to get this figured out. I tried to give you all of the data, if you need more info, please let me know.

Btw, will this batch even be drinkable, or am I just SOL?

Thanks!!!

PS: Thought I would do a go big or go home beer for my first AG, turns out I am a cocky idiot. Think I am gonna stick with some simple SMaSH brews till I get dialed in.

From what I can see and I am fairly new to AG but I would have to say you left a lot in the Mlt since you said you were not able to get all the wort out.
My guess would be the heavier sugars stayed in the bottom of your mash tun
Just a guess
D
 
I'd say go with a 90 min mash and try to lower your strike flow. Chances are, like my friend and I, that you didn't strike the heavier sugars out, since your drain is too high.
 
How much wort did you collect? You mention 5 gallons but that wasn't the pre - boil volume you collected was it? I'd also question the hydrometer reading of 1.034 and make sure your hydrometer is accurate. Was there any wort left in your mash tun after you were done?

I'm just guessing that with a bad crush, maybe low mash temps, slightly off readings and maybe not enough wort collected that combined to get your low efficiency.

I foresee a wonderful session ale in the making :) I hope it turns out nicely.
 
Thanks for all of the replies and help! Here is an update:

Firstly, I misjudged my wort collection volume, it was closer to 7.5gal, I misread which ring the level was up to in my keg (I guess that is what I get for brewing at 1:00 at night). This gave me a slight bump in efficiency to 41%. Still terrible, but a little bit more reasonable.

As for the causes of the bad efficiency, I am inline with you guys. I think it is a function of a poor crush and low temps. I calibrated my temp gauges and they were fairly close. I think my true mash temp was closer to 140-142f than to the 152f I thought I was at.

I added in the DME and my post boil OG going into the fermenter was 1.067. Not the 1.080 I was shooting for, but close enough considering...

I am curious to see if the beer turns out a little thin and dry considering the low mash temp. I will post the results when I sample the beer. She is bubbling away beautifully right now. After primary I am going to dry hop for 10 days with 2oz galaxy, then into the keg, carb, and down the hatch!

@MichaelBrock: By pre-boil OG, I meant pre-boil gravity. For my edification: is the term OG only supposed to be used for post-boil, into the fermenter wort? (probably a stupid question, but I am an AG newbie and want to get the terminology correct)
 
@MichaelBrock: By pre-boil OG, I meant pre-boil gravity. For my edification: is the term OG only supposed to be used for post-boil, into the fermenter wort? (probably a stupid question, but I am an AG newbie and want to get the terminology correct)

Yes, OG (Original Gravity) is the gravity measured immediately prior to fermentation. FG (Final Gravity) is the gravity measured at the completion of fermentation. I have also seen the FG occasionally referred to as TG (terminal gravity). When referring to a measurement regardless of what point in the process it is taken we use SG (specific gravity, the quantity we're measuring). So OG is the SG measured at the start of fermentation :cross:
 
Shouldn't be too thin with that extract in there, it's probably around 70-75% fermentable.
 
Yes, OG (Original Gravity) is the gravity measured immediately prior to fermentation. FG (Final Gravity) is the gravity measured at the completion of fermentation. I have also seen the FG occasionally referred to as TG (terminal gravity). When referring to a measurement regardless of what point in the process it is taken we use SG (specific gravity, the quantity we're measuring). So OG is the SG measured at the start of fermentation :cross:

Thanks for the clarification!
 
I have gotten up to 91% efficiency using a 10G round cooler with domed false bottom. The key to good efficiency is temperature, good mix, good crush, PH, proper time and slow sparge. I use 5.2ph stabilizer and typically about 152 temp @ 1.25qt/lb. Fly sparge IMHO gives you the best extraction and it must be done slowly. I usually sparge for at least an hour. Proper sparging cannot be underestimated. The idea behind the sparge is to wash the sugar from the grains so you get the best concentration of sugar per amount of water. Making sure to keep the hotter sparge water above the grain level allows the weight of the sparge water to push the sugars down and help extract more sugar as it works its way down. That is the reason for the slow sparge, it gives the time needed for the sugars to get pulled out of the grains to the greatest extent and get washed out as it moves down. Going slow also helps prevent channeling as you keep the water level above the grains.

Even if you don't get the efficiency you want your beer will still be good, just less abv but shouldn't have too much affect on flavor. I made several mistakes on my first mash and it worked out fine.
 
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