2nd BIAB, terrible efficiency!

opalko · 05-09-2011, 07:38 PM

Ok, this is my 2nd BIAB after brewing on a 3V system for a number of years. On my "old" set up with an "EasyMasher" (or homemade clone) I would normally get 75% efficiency - easily. My first BIAB I calculated the OG at around 1038 and ended up 1028-1030. This time I increased the grain bill and had an expected OG of 1050 (at 75% eff) and ended with a gravity of 1039 - 59% efficiency?!

The recipe
7 lb American 2 row malt
1 lb Crystal 40L
1 lb Amber malt
4 oz Corn sugar

.8 oz Goldings hops (5% AAU) - 60 minutes
.8 oz Fuggles (4% AAU) - 30 minutes

Wyeast #1469.

Grain crush same as I always use which is not a fine crush. Mash in at 151 F, 7.25 gallons, mash for 90 minutes, checking temp every 20 minutes. Temp averaged around 148 F. Added heat in small bursts occasionally if I saw temp dip to 146-7. Mash out at 151 F by pulling bag out and letting drip, squeezing what liquid I could get out of it by hand - (should I be running it up to 170 F first?)

90 minute boil, first 30 no hops. Ended up with 5.75 gallons wort. I don't really mind the gravity being lower - I prefer lower gravity brews but I'm not really sure why there is such a big difference in the gravity doing it by BIAB vs. 3V (I've brewed this one before).

Ideas?

Cheers!
Opalko

**mattmcl** · 05-09-2011, 07:40 PM

By 3V do you mean three vessels- hot liquor tank, mash/lauter tune, and kettle?

If so, you lose a LOT of efficiency by not sparging. I tried BIAB and got about 55%, but the same recipes done with a mash tun and batch sparging yield 80% efficiency.

opalko · 05-09-2011, 07:45 PM

Yes, 3 vessel system. I'm asking here because according to many who BIAB, they get very good efficiency:

http://www.homebrewtalk.com/f36/biab-brewing-pics-233289/

theschick · 05-09-2011, 08:35 PM

I'm pretty sure to make up for not sparging, you should crush the grains really fine.

**JPicasso** · 05-09-2011, 09:18 PM

Two things,

1. as theschick pointed out, crush it more. Either adjust the gap, or run the grain through your crusher a second time.

2. Run the temp up before pulling the bag, 170 or so.

Sounds like you kinda know what to change. And I suspect, your suspicions are correct sir!

Mysticmead · 05-09-2011, 09:24 PM

go a little finer with the crush. also mash out by raising to 165-168, pull the bag and let it drain. then squeeze it for every drop you can get.

also. was your recipe expecting 5 gallon of wort? I ran the recipe through beersmith. it looks like 75% for 5 gallons would get you right at the 1.050 you were looking for. the same recipe at 72% with 5.75 gallons gets you the 1.039-1.040 beer you ended up with. looks like the efficiency isn't that bad at all, you just made more beer than expected

**TacoBrew** · 05-09-2011, 10:55 PM

Quote:

Originally Posted by opalko

Ok, this is my 2nd BIAB after brewing on a 3V system for a number of years. On my "old" set up with an "EasyMasher" (or homemade clone) I would normally get 75% efficiency - easily. My first BIAB I calculated the OG at around 1038 and ended up 1028-1030. This time I increased the grain bill and had an expected OG of 1050 (at 75% eff) and ended with a gravity of 1039 - 59% efficiency?!

The recipe
7 lb American 2 row malt
1 lb Crystal 40L
1 lb Amber malt
4 oz Corn sugar

.8 oz Goldings hops (5% AAU) - 60 minutes
.8 oz Fuggles (4% AAU) - 30 minutes

Wyeast #1469.

Grain crush same as I always use which is not a fine crush. Mash in at 151 F, 7.25 gallons, mash for 90 minutes, checking temp every 20 minutes. Temp averaged around 148 F. Added heat in small bursts occasionally if I saw temp dip to 146-7. Mash out at 151 F by pulling bag out and letting drip, squeezing what liquid I could get out of it by hand - (should I be running it up to 170 F first?)

90 minute boil, first 30 no hops. Ended up with 5.75 gallons wort. I don't really mind the gravity being lower - I prefer lower gravity brews but I'm not really sure why there is such a big difference in the gravity doing it by BIAB vs. 3V (I've brewed this one before).

Ideas?

Cheers!
Opalko

I had the same issue with my first BIAB. After that I double milled the grain and jumped to 80%. Not sure if that's what you did. Are you sure your hydrometer is calibrated and did you adjust for temp?

**usfmikeb** · 05-09-2011, 11:04 PM

BTW, if you're getting low efficiency, you can still do a sparge. I use BIAB in the perforated part of a turkey fryer kit, and usually put it in my old 4 gallon pot after I pull it out of the kettle. If you test your batch and find the gravity is low, you can sparge it with some water and add it to the brew kettle. Of course, this assumes you have space left in your brew kettle.

I've done that to get to the gravity I was seeking.

opalko · 05-10-2011, 12:16 PM

Ok, I guess I was expecting the 75% on the 5.75 gallons. That would make sense if it should be 75% for 5 gallons. I'll adjust the mill to make a finer crush (I haven't changed the gap on it since using it for a 3V system). Some good help here, thanks!

Jaimez · 05-11-2011, 01:55 AM

Quote:

Originally Posted by usfmikeb

BTW, if you're getting low efficiency, you can still do a sparge. I use BIAB in the perforated part of a turkey fryer kit, and usually put it in my old 4 gallon pot after I pull it out of the kettle. If you test your batch and find the gravity is low, you can sparge it with some water and add it to the brew kettle. Of course, this assumes you have space left in your brew kettle.

I've done that to get to the gravity I was seeking.

+1 Sparge if you can. Theres no reason not to.