Consistantly low extraction

[gundarak]

Hey all!

Before we begin, glad to be a new member here, but hope you dont mind if I just jump right in! FYI, Yes, I have read the low efficiency stickies before posting this.

For my last 4 or 5 brews, Ive had consistently low efficiencies. If you ask me what those are, I couldnt tell you, but I can remember that in the end, they were at least 1-2% abv lower than estimated.

Every batch I have tried to improve on my methods, and I finally feel that this issue I am seeing is not related to my procedure, but to the grain itself, but I still wanted everyones opinions. Here is all the information I can remember off the top of my head.

-I use my barley grinder with a power drill
-Im using stale 2 row grain as the base of my recipes
-Until my new equipment is built, my mash/lauter tun is my brew pot.. so my sparging is done through batch sparge and an auto siphon.

things I have done to increase efficiency (but it didnt)
Adjusted my malt crusher to a finer grain
ran the malt through two passes in the crusher
Used a rectangle cooler mash tun
I had read that an increased mash time would help rehydrate stale malt and increase extraction. I almost saw no difference..
Used filtered tap water, let sit overnight

In particular, here is some stats from the latest test batch
Saison, 4.5g batch... est OG 1.063 / FG 1.014 (6.5%)
0.25 oz Hallertauer [4.80 %] - Aroma Steep 2.0 min
0.25 oz Hallertauer [4.80 %] - Boil 30.0 min
0.25 oz Saaz (Czech) [4.00 %] - Aroma Steep 2.0 min
0.25 oz Saaz (Czech) [4.00 %] - Boil 45.0 min
0.50 oz Hallertauer [4.80 %] - Boil 60.0 min
0.50 oz Saaz (Czech) [4.00 %] - Boil 90.0 min
1.0 pkg Belgian Saison I Ale (White Labs #WLP565)
1 lbs 12.0 oz Caraamber (Weyermann) (36.0 SRM)
9 lbs Pale Ale Malt 2-Row (Briess) (3.5 SRM)
Mash 5.25gal @ 154F for 2 hours
1 step batch sparge (2.50gal @ 168F)
150 min boil (originally 90 min boil, but this was 6.25 gal of water on a stove top, needed to boil down to 4.5 gal)
results: 4.5 gal 64F @ 1.050

Thoughts? questions for clarification?

 

[flars]

Mashing at 148°F will improve your extraction efficiency and lower the FG.

 

[ncbrewer]

Welcome to HBT.
I see you've tried crushing finer - maybe it's still not fine enough.
Try stirring well before starting the run-off if you haven't already.

 

[gundarak]

Thanks for the input guys, and the warm welcomes!

You guys dont think the age of my malt may be part of the issue? This malt is literally over a year old.. kept in good storage conditions, but you know.. stale.. every batch i have done with this stale 2 row has been very low yield.

@flars - yeah my aim was 148F honestly, but I was borrowing a mash tun that wasnt mine, so i didnt know the equipment. It held the temp more than I thought, so my strike temp was a little too high.. wasnt any way to turn back

@ncbrewer - yeah I read somewhere you want to adjust the crusher so "it will grab onto a credit card".. prior to adjustment, the card would just slip through.. I adjusted it where the card would be stopped, then tightened it a mm further.. do you still think it wouldnt be fine enough?

Also, yes, after this post.. I did some more reading on here and other sites, and learned I may not be batch sparging properly.. I didnt do any of the recommended things.. like.. stir for 3-5 mins prior to lauter.. i didnt disrupt or stir the grain bed either during sparge.. i read that batch sparging you need to stir and disrupt constantly?

 

[chickypad]

Thanks for the input guys, and the warm welcomes!

You guys dont think the age of my malt may be part of the issue? This malt is literally over a year old.. kept in good storage conditions, but you know.. stale.. every batch i have done with this stale 2 row has been very low yield.

@flars - yeah my aim was 148F honestly, but I was borrowing a mash tun that wasnt mine, so i didnt know the equipment. It held the temp more than I thought, so my strike temp was a little too high.. wasnt any way to turn back

@ncbrewer - yeah I read somewhere you want to adjust the crusher so "it will grab onto a credit card".. prior to adjustment, the card would just slip through.. I adjusted it where the card would be stopped, then tightened it a mm further.. do you still think it wouldnt be fine enough?

Also, yes, after this post.. I did some more reading on here and other sites, and learned I may not be batch sparging properly.. I didnt do any of the recommended things.. like.. stir for 3-5 mins prior to lauter.. i didnt disrupt or stir the grain bed either during sparge.. i read that batch sparging you need to stir and disrupt constantly?

Looks like about 58% efficiency on your last batch. When batch sparging you do want to stir like crazy after adding your sparge water. Once that's done you can just drain away as fast as it will go, you don't need to stir during the lautering. If you don't stir well initially you might not be leaving some sugars behind. The mash temp of 154 should not adversely affect efficiency, it might change your fermentability.

Are you saying that you only had efficiency problems when you started using this malt? It's hard to tell from your post, but if your efficiency was fine before and only a problem with this grain then I guess that is suspicious. I've used almost 2 yr old grain before though with no issues. Do you know your water and are you checking pH? You can also post a pic of your crush next time.

 

[ncbrewer]

This website has some info about adjusting the crush: http://braukaiser.com/wiki/index.php?title=CrushEval

This one has some info about sparging: http://hbd.org/cascade/dennybrew/

I hope this helps.

Edit: I haven't read anything about stale grain causing low efficiency, so I can't help with that.

 

[acidrain]

Your title indicates you are looking at mash efficiency, but then you go on to talk about final ABV. Efficiency is not calculated by whether or not or alcohol level is as high as predicted.
There are two basic ways to calculate efficiencies... mash efficiency, and brewhouse efficiency.
When you're talking about extracting sugars, that would fall into the mash efficiency category where you collect wort, the volume is measured (exactly), and the gravity is read (exactly). Brewhouse efficiency is where you take the same readings, except AFTER boiling, cooling, and going into the fermentor. Your losses will be factored in (trub loss, equipment loss, etc.)
Temperature plays a roll in this as wort expands when hot, and hydrometers/refractometers are read at (usually) 60 or 65 deg. F.
Accuracy with volumes, specific gravity, and temperatures is essential to gathering the data to find for either efficiency.
Final alcohol levels are affected by many things... maybe your wort was too dilute (more volume that anticipated), or your sugars were too low (poor mash efficiency), or you mashed too high in temperature or were not able to hold temperature (resulting is some un-usable sugars).
I think you need to take better notes/readings before declaring your lack of conversion is causing low ABV's.

 

[gundarak]

@chickpad - im going to be brewing this weekend again, and ill make sure to improve my methods on sparging.. i think this may be part of the issue. I'll run some pH tests and get a pic of my crush for you

@ncbrewer - thanks for the links, i'll give them a good read

@acidrain - your absolutely right, im a bad note keeper. I tend to have too much fun and forget all about documentation, then get all confused at the end of it all. I'll approach this more seriously this weekend and see what the numbers look like. Thanks for explaining the efficiency differences.. i'll try to document both!

Thanks for the input! I'll keep you guys in the loop.

 

[gundarak]

Alrighty,

I know a few have been waiting for me to reply on this, and I think I may have found whats going on.

To start, I have to admit that this batch was probably the best that I have done. All estimations on volume and even boil evaporation were spot on, I really havent had that before. It was also a pumpkin beer, with no stuck sparge.. it was a really good day.

Target volume in fermenter: 4.5 gallon batch
here are the details:
forgive the random qtys.. i was getting rid of small amount of leftover grains.
3 lbs 12.0 oz Pumpkin
2 lbs Rice Hulls
7 lbs 4.0 oz 2-Row
1 lbs 4.0 oz Caramel/Crystal Malt - 60L
1 lbs 4.0 oz Wheat Malt, Dark
1 lbs Munich I

Mash In Add 20.63 qt of water at 163.7 F - hold at 152.0 F 60 min
Drain mash tun, Batch sparge with 1 steps (2.17gal) of 168.0 F water
boil volume of 5.35 gal
Estimated Post Boil Vol: 4.68 gal and Est Post Boil Gravity: 1.066 SG
Actual Post Boil vol: ~4.6 and actual Post boil gravity: 1.050 SG

Pics of my grind are attached, as requested.. sorry about the quality, but i think you get the point.

Again.. all the numbers were met on the money, except for the gravities again...

During the post boil gravity reading, I chilled a small portion of it to reduce the temp, and then checked the temp with my digital probe thermometer. something felt funny, so I checked it again with my handheld digital thermometer, and the reading was 20F COLDER than the probe.. I used a 3rd analog thermometer, and this read the same as my handheld digital. This led me to suspect my probe thermometer of being bad, reading higher than the actual temp. I boiled some water and submerged the probe and my handheld.. and read the difference.. my handheld read 208F, and my probe read 228F.. I think that confirms it....

Ive been using my probe thermometer to read the temperature of my mash and sparge waters, as well as monitoring my mash during mash-in. If my suspicions are right, then that really means im mashing in about 10-20 degrees cooler than what I should be, causing me to have little or no extraction...

Since I actually used all 4 of my carboys, im going to have to wait until one of them becomes free to confirm this by using a different thermometer through the whole process, and checking my numbers again..

If this is my problem, can you guys direct me in what you use for thermometers? I trusted my digital probe too much apparently, and dont think i can trust digital again.

thoughts?