Why the bad biab efficiency?

[citizensnips]

Ok, firstly let me start my saying all my AG beers have been well up to scratch, so at least the main issue of making half decent beer isn't a problem. However for some reason my efficiency is just plain out crap, I've been trying to figure out with batch size and what not how it effects efficiency but basically for a 26L batch I get 63% efficiency. I BIAB and use a keggle as my pot, I mash for an hour with ale base and pilsner 75 (doesn't make much difference really, efficiency still sucks). I also have to add direct heat to the keggle to keep it around my mash temp, say like for an APA I did yesterday at about 66-67C I will fluctuate between 64-68 throughout the mash, most of the time hitting where I want it. I also have an insulation sleeve I made for the keg, however temp still doesn't hold all that well. Sometimes I may do a quick dunk sparge but asides from that I really just squeeze the grain bag good to get the majority of liquid out of it then remove it. Heres the recipe print out from the APA I did yesterday. ended up getting 63% efficiency and hitting 1.046 instead of 68% and hitting 1.050. So if any of you experienced AG folk can pick up on anything I can do to improve my terrible efficiency it would be greatly appreciated.
Thanks

Style: American Pale Ale
TYPE: All Grain
Taste: (30.0) 

Recipe Specifications
--------------------------
Boil Size: 35.10 l
Post Boil Volume: 31.20 l
Batch Size (fermenter): 26.00 l   
Bottling Volume: 25.20 l
Estimated OG: 1.050 SG
Estimated Color: 15.1 EBC
Estimated IBU: 32.0 IBUs
Brewhouse Efficiency: 68.00 %
Est Mash Efficiency: 78.5 %
Boil Time: 60 Minutes

Ingredients:
------------
Amt                   Name                                     Type          #        %/IBU         
5.20 kg               Pale Malt, Ale (Barrett Burston) (5.9 EB Grain         1        85.2 %        
0.50 kg               Caramunich Malt (90.0 EBC)               Grain         2        8.2 %         
0.40 kg               Wheat Malt (Barrett Burston) (3.0 EBC)   Grain         3        6.6 %         
9.00 g                Warrior [15.00 %] - Boil 60.0 min        Hop           4        12.2 IBUs     
15.00 g               Citra [12.00 %] - Boil 15.0 min          Hop           5        8.0 IBUs      
10.00 g               Mosaic [12.00 %] - Boil 15.0 min         Hop           6        5.4 IBUs      
20.00 g               Citra [12.00 %] - Boil 5.0 min           Hop           7        4.3 IBUs      
10.00 g               Mosaic [12.00 %] - Boil 5.0 min          Hop           8        2.2 IBUs      
1.0 pkg               Safale American  (DCL/Fermentis #US-05)  Yeast         9        -             


Mash Schedule: BIAB, Medium Body
Total Grain Weight: 6.10 kg
----------------------------
Name              Description                             Step Temperat Step Time     
Saccharification  Add 38.83 l of water at 70.8 C          66.5 C        60 min        
Mash Out          Add 0.00 l of water and heat to 75.0 C  75.0 C        0 min         

Sparge: Remove grains, and prepare to boil wort
Notes:
------

 

[Sam England]

Arvo Eddy22,
I'd be having a look at your grain crush size first to see whether you can drop your mill settings as BIAB is pretty forgiving. I used to run a similar BIAB setting to yours and I consistently hit 80%. I milled my grain at a 1mm setting and for 24L into a fermenter I'd mash in with 23-24L, heat to 72 for 10 to ensure full conversion and then mashout at 78 for 10. I'd then have two buckets of 5L 78deg water which I'd drop the bag in, stir for a bit, let sit for a couple, drain and then the same for the next. It was always surprising how high the SG of the last bucket was. Basically the wort trapped in your grain is the same SG as your initial mash and by diluting it at least once or twice you get most of these sugars out. I've never had any issues with off tastes doing it this way, but you do get a bit more crud in your pot after the boil due to the extra dunking etc. Not too much of an issue in my opinion though.
Good luck.
BB

 

[Nick JD]

What's you thermometer read against another (say an STC1000), and what's it read in ice water and in boiling water?

You might well be mashing at 60C, in which case, you need to mash for about 2 hours+ to get a decent conversion.

Have you done a starch test?

 

[Crusty]

80% efficiency + for me with my Biab in the Urn.
Things I consider a must for excellent efficiency with Biab are:
1: Grain crush. My mill is set to 0.9-1mm
2. A 90min sacc rest will give you better conversion than the traditional 60mins.
3: Mash out. Raise the temp from sacc rest to 78deg for the mash out. It is essential to constantly rouse the mash whilst heating.

 

[Liam_snorkel]

OP - there is a spreadsheet on this other forum called "the calculator" which is a tool for calculating your BIAB efficiencies..
it calculates your efficiency into boil (mash eff.), end of boil, into fermenter, & brewhouse..

It could help you establish where your efficiency loss is coming from, ie mash eff, actual boil off rate, actual trub volume..

 

[fletcher]

80% efficiency + for me with my Biab in the Urn.
Things I consider a must for excellent efficiency with Biab are:
1: Grain crush. My mill is set to 0.9-1mm
2. A 90min sacc rest will give you better conversion than the traditional 60mins.
3: Mash out. Raise the temp from sacc rest to 78deg for the mash out. It is essential to constantly rouse the mash whilst heating.

could i also ask for some clarification - with milling grain - as i also BIAB and wanna get an idea of what that size/setting means. i use a coffee grinder. would it just be 'grind the crap out of it until it's almost all powdery or do you want some hull in there?

 

[citizensnips]

Thanks all for the replies.
Grain crush is one thing I definitely considered but haven't been in control of as I get it pre milled from either store I order from. Fortunately however I have my very own mill on the way soon so I'll be doing a fine crush with that for sure. I also already mash out (forgot to put that in), can't tell if it does anything but it sure as hell doesn't hurt so I'll continue with it. Will consider doing an even longer rest in the future, but not too convinced on how much that does......can't hurt to experiment with the same recipe though and see the difference. I also tested the temp of the mash with my infrared thermo, I did it by stirring the mash and just measuring the surface, and that read within 1 degree of my kettle thermometer, but I should do a few more tests to be confident that I'm not being fooled. And Blue Baggers maybe I'll give a little sparge in some 78 degree water a crack, see if it does anything. A lot of experimenting to do!

 

[slash22000]

could i also ask for some clarification - with milling grain - as i also BIAB and wanna get an idea of what that size/setting means. i use a coffee grinder. would it just be 'grind the crap out of it until it's almost all powdery or do you want some hull in there?

There's not really any way to translate a mill setting to a coffee grinder but the grain should never be "powder" ...

 

[Crusty]

could i also ask for some clarification - with milling grain - as i also BIAB and wanna get an idea of what that size/setting means. i use a coffee grinder. would it just be 'grind the crap out of it until it's almost all powdery or do you want some hull in there?

I'd seriously consider ditching the coffee grinder which is perfect for grinding coffee but we don't wan't to grind our grain, we just want it cracked so the hot water has access to the starch inside. I know mills are an expensive item in the brewery but it's an essential part of mine. I have the MashMaster MiniMill which is brilliant. If you don't have the coin for a mill at the moment, the site sponsors offer a free milling service. This option would be way better than the coffee grinder.

 

[fletcher]

cheers for the replies guys and yeah i'll get a mill in coming months. sorry to hijack the thread eddy mate

 

[malt_shovel]

. So if any of you experienced AG folk can pick up on anything I can do to improve my terrible efficiency it would be greatly appreciated.
Recipe Specifications
--------------------------
Boil Size: 35.10 l
Post Boil Volume: 31.20 l <------
Batch Size (fermenter): 26.00 l <------
Bottling Volume: 25.20 l
Estimated OG: 1.050 SG
Estimated Color: 15.1 EBC
Estimated IBU: 32.0 IBUs
Brewhouse Efficiency: 68.00 %
Est Mash Efficiency: 78.5 %
Boil Time: 60 Minutes

I think the main problem is the amount of wort you leave in the kettle.

Currently your post-boil volume is 31 odd Litres, but only 26 make it to the fermenter, so you have 5 litres of concentrated wort lost to the trub.

If you can reduce this down to say 1 litre (I think this is doable with various methods), then I think your efficient would be far greater.

If I have my maths right, if you extracted the same amount of sugars with a smaller volume that boiled down to 27 litres, this should have a gravity of 1.053 (better than you hoped!).

I think you are getting conversion, it is your losses to the kettle which is killing you. Get this number down as low as possible and you will get your extra efficiency everyone seems to be desperate to achieve (I think 68% is fine. horses for courses).

Hope that helps

 

[felten]

I would say there is a difference between mash efficiency, and efficiency into the fermenter. And everyone measures it at different places.

If you are taking the kettle losses into account your efficiency is going to look quite low, as BIAB loses more to the kettle than other methods. Your mash efficiency might be fine, but you need to cut down on the losses to increase your efficiency into the fermenter.

Plugging your numbers into my BS2, it says 75% efficiency (though my BS2 might be set up weird).

It's worth reading these articles and breaking the calculator out to manually work out efficiency. You might not be as bad off as you think.
http://braukaiser.com/wiki/index.php?title=Understanding_Efficiency
http://braukaiser.com/wiki/index.php?title=Troubleshooting_Brewhouse_Efficiency

 

[Rowy]

I measure efficiency by the OG of the wort going into the cube. I generally get aqbout 66 to 70. Done about 70 BIAB brews. Batz gave me a bit of advice once and it was this........................Efficiency is about a handful of grain one way or the other. If it tastes OK who gives a F$#K.

Crusty's advice is pretty spot on I reckon if you want to look for something.

Going to 90 minutes rest WILL make a difference of 3 or 4 points at least, That along with mashing out at 78ish while stiring constantly while ramping up could add a bit more. Do both! I do.

 

[beerdrinkingbob]

whilst I agree with Rowy it does add up over time and you can spend that on more toys!!!!

I use a keggle and get 32 litres of 1.060 from 8.5 kg of grain and water it down. My grain to liqour is **** (4 to 1), the only reason it works is an ultra fine crush and rests at 72 and 78 ( both 10 minutes) and get 68 to 70% into the fementer. I do dunk sparge into 8 litres to replace the grain volume for 10 minutes into the old 19ltr big w pot.

Would rather not dunk the bag but hey very cheap system!!

Good luck

BDB

 

[Crusty]

As Rowy pointed out, simply changing the sacc rest time from 60mins to 90mins & ramping the mash to mash out, constantly pumping the mash with the paint stirrer, my efficiency went from 75-77% to 80% +. The longer contact time at sacc rest temps is so beneficial to full volume brewing, it simply works & works well.

 

[Tex083]

Hi in the recipe I noticed you had no "salt" additions.
I have been putting some time into researching how water chemistry affects mash efficency and pH. When I first read over it in how to brew I was more confused than when I started. I kept looking for a "good" article or spread sheet, I see your in Melbourne too.
READ THIS: http://www.melbournebrewers.org/index.php?option=com_content&view=article&id=114:key-concepts-in-water-treatment&catid=48:ingredients&Itemid=103
It gives it to you in simple tearms and is REALLY good. I also had a Beersmith article on water chem, it was a bit confusing as its all imperial. Brad Smith talked about only hitting 65-70 Eff with his BIAB before playing with salts now he hits 80% changing NOTHING else.

"Calcium increases mash acidity. Calcium is advantageous to the brew. Calcium stimulates
enzyme activity and improves protein digestion, stabilizes a-amylase, helps gelatinize starch and improves
lauter run-off. It also extracts fine bittering principles of the hop and reduces wort colour……….improves
hot-break flocculation…….essential part of yeast cell composition……neutralizes substances toxic to
yeast, such as peptone and lecithin. It improves clarification during aging, as well as the stability and
flavour of the finished beer.”

Need I add more???
Get some calcium into your beer!

 

[citizensnips]

Wow thanks for the quality replies. I knew some one would pick up on the left overs in the kettle. The problem is the ball valve is about 4L above the bottom of the keg. Those figures aren't quite correct, Id leave about 3.5L in the keg. I was given it so I wasn't exactly going to complain. I could syphon it off the top however there is quite a lot of trub, at best I would have to leave 2.5L abouts max, otherwise I would be sucking up pure crud from the kettle.
From what you guys have written I'm going to try
1) Increasing mash to 90mins
2) Finer crush
2) Stirring while mashing out is one thing I have never done so definitely going to do that as well.

p.s. Tex that article is incredible, I looked for something identical for that for so long and thought it didn't exist! I'll have a proper read and see what I can take out of it.
Thanks a lot for the replies, I think I should be able to increase my efficiency a noticeable amount, maybe one day I'll hit 70% :lol:
Cheers and beers

 

[malt_shovel]

Before you forget about this post and to make it more useful for someone who next comes across it could you please clarify how you are measuring efficiency? As pointed out by felten and other in numerous posts, efficiency can be calculated for any part of the process. Cheers and good luck squeezing out those extra points.

 

[citizensnips]

Good point, I had my numbers entered in on beersmith, so for 68% efficiency I would get an OG of 1.050. I took a hydrometer reading and got an OG of 1.046, so I just changed my efficiency on beersmith untill it estimated an OG of 1.046 which ended up being 63%

 

[Aydos]

I'm sure that's brewhouse efficiency on beersmith which in that case isn't really that bad. I get around 78% mash efficiency and around 68% brewhouse efficiency so I don't think your far off the mark. I'm happy enough with 68% BE.