Help! Low Efficiency...why?

I've been all-grain brewing for about a year and can't figure out why my measured OG is so much lower than expected. Maybe it's my equipment, when I'm measuring the OG, how quickly I'm lautering, how much sparge water I'm using, etc. I've been able to make some solid brews, but the OG is always lower than expected. BeerSmith tells me my efficiency is usually about 45-50%.

Here are a couple pictures of my mash tun:
http://www.homebrewtalk.com/photo/photo-oct-14-10-27-00-am-56870.html
http://www.homebrewtalk.com/photo/photo-oct-14-10-27-17-am-56871.html

I've been measuring the OG right before I put the wort into the fermenter (after I've cooled it down). When lautering, I continuously sparge for about an hour.

Any ideas? Thanks in advance!
-Sam

 

Also, look into the quality of your grain crush. This is often the issue when you have poor efficiency. If the grain is not crushed fine enough you will not be able to extract a high percentage of the available sugars.

 

Thanks, will give it a try. Also, should I measure OG before the boil?

 

Yes, That's your preboil SG. Knowing that can help you know if you need to boil longer or dilute, before you add your hops so you can adjust the schedule/amounts accordingly

 

Thanks. I've typically had my LHBS crush the grain. I've never really asked them about how fine they crush it up. Is there a certain amount I'm looking for? Would it be better to crush my own grain?

 

Look at the grain they've crushed. If you see ANY whole grains, it's not good enough. I crush pretty fine (I also use a braid like you) and as long as there's some husks to form the lauter bed, you'll be just fine.

 

+1

My first 3, or 4 all-grain batches I got terribly LOW OG and the crush was the problem! I have the braid like you too, now I have to tell the LHBS every time i go in to move it down a notch from 5 to 4 on their crusher and that does the trick for me. The last I don't know how many batches in a row now my OG has been spot on or even slightly high

Good luck!!

 

This! Batch sparge and you should get 10% increase.

 

Any tips on batch sparging? I've never done it.

 

See http://hbd.org/cascade/dennybrew/

I think you can get slightly better efficiency fly sparging than batch sparging if you have the right setup, and take sufficient time. If you don't have the right setup, or try to rush things, then you can get terrible efficiency with fly sparging, but it's hard to get poor efficiency with a batch sparge providing you stir in the sparge water sufficiently before vorlaufing and draining.
http://www.howtobrew.com/appendices/appendixD.html gives what I consider to be good information on how to build a MLT suitable for fly sparging.

-a.

 

Completely drain the 1st runnings. Add 100% of your sparge water, give it a good stir, rest for a few minutes, drain second runnings as you did the first (set grain bed, vorlauf). Combine 1st and 2nd runnings and boil.

 

I have a braid in a water cooler. My efficiency has increased dramatically by asking my brew shop to double mill the grain (when they're not extremely busy). This is just temporary, until I get my own mill. I also stir the mash every 15 minutes or so. I let it rest for the last ten minutes so that the grains settle and drain it entirely. Then I add all my sparge water, stir for a couple minutes, let it rest for 10, then drain. I vorlauf 2 liters of wort each time I drain.

 

I wouldn't worry about stirring mid-mash. The temperature losses aren't worth it. I never have and I hit 80% every time. Stirring extensively when you dough-in is key. I used a wire whisk last brew and was amazed at how well it eliminated dough-balls. My grist was like velvet.

I stir before each run-off, though. Typically I vorlauf about 60oz, pour that back in via a colander, and run off very slowly.

 

evans,

Are you taking your readings after you sparge or after you boil? How do your beers taste? Are they about what you expected or thin and more bitter than you planned? If your measuring with a hydrometer pre-fermentation, I've found those little hydrometers can be very inaccurate. They really are better for post-fermentation. Sometimes that little paper shifts, too. I've used mine next to refractometers and have been 10-12 gravity points apart at times. If your crush is even just a cracked crush and you don't sparge, you should be getting 65-70% efficiency no problem.

 

I've been reading the gravity after the wort is cooled down, post-boil, and about to put it into fermenter. My beers have tasted good, but I've never hit high efficiency, so I don't know what they could taste like with that. Quick newbie question...is it okay to measure the wort gravity once it's all in the boil pot before the boil or is it too hot for the hydrometer to handle?

 

So general process is:

Pour in grains and water, stir, Mash for ~60 min, stir, let sit 5 minutes so grain bed settles, vorlauf and pour back in about 60 oz., drain until wort stops coming out (rate not that important?)

Pour in all of sparge water, stir, let sit 5 minutes so grain bed settles, vorlauf and pour back in about 60 oz., drain until wort stops coming out or boil pot is full

Sound about right?

 

Man... Your process sounds fine. Someone else might knit-pick it, but there's no way you're getting 45-50% efficiency. That's the kind of efficiency you would expect if your grain was whole-husk and not crushed at all. If you were getting that kind of efficiency, you would notice the imbalance in your beers. Are you measuring your final gravities, too? If they are around 2-4 points what you calculated, I would say that your OG isn't too far off.

You can measure your pre-boil gravity. You can take a sample of your wort and stick it in the freezer. Let it cool down to 60. It won't take much wort if you have a wine thief. That, or get a refractometer... but I wouldn't be concerned unless your beer is tasting way off from what you expected. If it tasted like you intended, who cares what the measurements read. There's too many variables with those hydrometers...

 

The general process I listed above wasn't the one I was using. I was fly sparging for 30min-1hr and that was getting me ~50% efficiency.

 

listen to Yooper!

 

Yes, except I don't let it sit 5 minutes, I just start vorlauf. I run off slowly mostly because I don't want to have so much pressure that I get stuck/super slow runoff. I'd say 1/3-1/2 open valve is about where I usually run-off.

 

Thanks all! Looking forward to next brew day. Thinking of doing a clone of dfh 90 min. Ipa.

 

This taught me to batch sparge. Denny is the man. I saw his website link posted, but this is a BeerSmith podcast he did on the subject. Very helpful with many questions answered!