Modified BIAB: hitting 85%+ efficiency

I've just started AG and after reading a bit decided to go BIAB for a little less equipment up front. I've been doing it a little bit modified though, since my 7.5 gallon kettle isn't quite large enough for a full 5.5 gallon BIAB batch.

So what I do is mash in the bag with 5.5 gallons (and the grain takes up the rest of the volume in the kettle.) After 60 mins I pull out the bag and dunk it in another bucket with 2.5 - gallons of water, then pour that water into the kettle as well.

My first 2 batches both produced over 85% efficiency. It would have been about 67% efficiency with the initial volume alone. The bag dunk got me another 18-20%. I am pretty happy with that, and it is really no trouble to do either.

The dunk was your sparge. Good idea, great results.

that is EXACTLY what I've been doing. I, too, regularly get efficiencies in the 80s. Just curious though, what is your water to grain ratio in the initial mash dunk?

My 2 grain bills have been 12 and 13 lbs, and I went with 5.5 gallons just b/c that's about all i can fit in the kettle. So 22 qts/12 lbs is almost 2 qts/lb.

My OGs are getting too high though (i expected more like 70-75%), so I can drop down to more like 10-11 lbs of grain and then I'll be over 2 qts/lb.

Man, I can't wait to start AG brewing. I know that I want to start with BIAB since it is the easiest equipment upgrade from extract, and I keep reading great posts like this making me think it is a good idea. I just hope I don't forget all this information...

Is there any way to subscribe to threads? I see people talking about doing it, but I can't seem to find the button...

jaginger said:

My 2 grain bills have been 12 and 13 lbs, and I went with 5.5 gallons just b/c that's about all i can fit in the kettle. So 22 qts/12 lbs is almost 2 qts/lb.

My OGs are getting too high though (i expected more like 70-75%), so I can drop down to more like 10-11 lbs of grain and then I'll be over 2 qts/lb.

Click to expand...

yeah, im atleast 1.5 qt/lb in all my BIAB. The high ratio might be the cause of the good efficiency. People will neighsay about how a high ratio extracts all kinds of unwanted flavors from the grain, but my beer tastes good, thats all that matters.

Gardenhead said:

Man, I can't wait to start AG brewing. I know that I want to start with BIAB since it is the easiest equipment upgrade from extract, and I keep reading great posts like this making me think it is a good idea. I just hope I don't forget all this information...

Is there any way to subscribe to threads? I see people talking about doing it, but I can't seem to find the button...

Click to expand...

at the top of the thread there's a drop down menu that says thread tools. just click on that and then there's an option that says subscribe to thread

Retarded_Penguin_Brewing said:

at the top of the thread there's a drop down menu that says thread tools. just click on that and then there's an option that says subscribe to thread

Click to expand...

Thank you! I totally missed that entire menu

Nice! This BIAB thing is becoming my recommendation for beginner all grain brewing, it's cheap, easy and it works!

Yes i did 1 brew in the bag batch and im thinking about doing more..cleanup is a breeze

I can't wait to try my first AG BIAB. I want to do a SMaSH (so that I can focus on process) but I'm also thinking about making my Magic Hat #9.5 recipe to keep SWMBO into brewing.

alcibiades said:

yeah, im atleast 1.5 qt/lb in all my BIAB. The high ratio might be the cause of the good efficiency. People will neighsay about how a high ratio extracts all kinds of unwanted flavors from the grain, but my beer tastes good, thats all that matters.

Click to expand...

Haha, you said "neighsay"

lol this is how you are suppose to do it, so I don't think you modified anything

Saccharomyces said:

Nice! This BIAB thing is becoming my recommendation for beginner all grain brewing, it's cheap, easy and it works!

Click to expand...

+1! I've had a couple all grain converts under my belt showing them this method. It's great.

mightynintendo said:

Haha, you said "neighsay"

Click to expand...

what? dont people who nay say sound like horses?

DavidSteel said:

lol this is how you are suppose to do it, so I don't think you modified anything

Click to expand...

Well i just didn't want to run afoul of the BIAB "purists" (how's that for an oxymoron) who would say it's not true BIAB because I did the sparge. I think the Aussie version is meant to be all in one vessel with full volume.

I do the same thing and I also end up with like 80%+ efficiency also. My first couple recipes were accidental imperials. I think it was also because of the fine crush that bmw gives their grains. I love it and I don't think I'm going to upgrade for a long time. I am currently an apartment dweller so it's great to save space and it's great for 3-5 gallon batches

Whats the biggest amount of grain you tried this with. I have done this for a couple small batches 10-13#s and was thinking about pushing the limits of my equipment with the DFH 90 min clone. I guess I am just curious to see if anybody has done any big beers with this method


I have a 7.5 Gallon pot as well

DFH 90Min Clone
5 gal
OG 1.088 FG 1.021
IBU 90 SRM 13 ABV 8.7%

16.5 lbs Pilsner Malt
1.66 amber malt

2.00 oz Amarillo 8% AA 90 - 0 minutes
.62 oz Simcoe 10% AA 90 - 0 minutes
.53 oz Warrior 15% AA 90 - 0 minutes
1.00 oz Amarillo Dry
.50 oz Simcoe Dry
.50 oz Warrior Dry

My biggest grain bill was 13 lbs. I think more is certainly possible if you reduce the initial water and do a bigger sparge.

So, I have a 9 gallon kettle. Would you reccomend doing the dunk for efficiency purposes, or would i have enough room in a 9 gallon kettle to do a standard gravity beer without using another vessel?

jaginger said:

Well i just didn't want to run afoul of the BIAB "purists" (how's that for an oxymoron) who would say it's not true BIAB because I did the sparge. I think the Aussie version is meant to be all in one vessel with full volume.

Click to expand...

Yes, as a BIAB purist, you have offended me to no end j/k

Do what works for you. I get 80% with full volume no-sparge BIAB and I'm pretty happy with that.

God I love the biab with a sparge: BIABWAS.

Did a pale ale today. 14 qts strike on 9.5lbs of grain, 13 qt sparge. Hit 84% efficiency. I spent $10 on a 5gal cooler (did NO modifications to it) and a $1 paint strainer. No false-bottom, no vourlaufing and no worries.

I have no frickin' idea why some people agonize over 60% efficiency with fancy-ass all-grain setups. Get a paint-strainer and be done with it. I might move to a nicer setup one day, but BIABWAS was the only way I could get into all grain, and is serving me well right now.

For me, the reason I don't BIAB is because it's too simple. Brewing is a hobby, and I enjoy getting senselessly complicated sometimes. Also, the purist in me just won't allow it. It wouldn't be a bad idea for a smaller beer, but for the most part my grain bills are upwards of 13 pounds of grain for 5-gallon batches. Heavy!

Jzak09 said:

Whats the biggest amount of grain you tried this with. I have done this for a couple small batches 10-13#s and was thinking about pushing the limits of my equipment with the DFH 90 min clone. I guess I am just curious to see if anybody has done any big beers with this method

Click to expand...

We did a partigyle style brew session a bit ago. We called it collaborative brewing. Two mashes, 3 big beers and 2 bonus sour beers to boot. My rig was the BIAB. The "sparge" in my case was for half the second beer. I had 23# of grain in my 15 gallon kettle. Lifted, twisted, and drained for a bit on my own. No hoists, no hanging. Just my two scrawny arms. We were the "Partigyles gone wild" podcast on Basic Brewing Radio.

Here's my blog of it:
Collaborative Brew

BIAB is very flexible. It can be as simple or as complicated as you want to make it.

jaginger said:

After 60 mins I pull out the bag and dunk it in another bucket with 2.5 - gallons of water, then pour that water into the kettle as well.

Click to expand...

Was the 2.5 gallons of water heated to a certain temp?

fidjit said:

Was the 2.5 gallons of water heated to a certain temp?

Click to expand...

The water was about 180 b/c I wanted to get my grain bag up to 170 when I dunked it. Not sure if that really matters but it's the way I did it.

mightynintendo said:

It wouldn't be a bad idea for a smaller beer, but for the most part my grain bills are upwards of 13 pounds of grain for 5-gallon batches.

Click to expand...

I can theoretically make barley wine with my setup. (I just don't care for the stuff.)

I think 13lb would probably be a little heavy for a single paint strainer bag, but you should be able to simply double-up the bag by using one inside of another, and that would give you the bag strength to hold the grain.

However, any more than say, 12 lbs of grain mashed at a volume of 1.25qt/lb and you'd probably run out of room in the 5 gallon cooler.

At 85% efficiency (pretty normal for BIABWAS) I can use 12lbs of 2-Row and get a starting gravity of 1.075 for a 5 gallon batch. That's hardly what I would call a "smaller" beer.

Also, it seems like a lot of my recipes call for .5 to 1 lbs of other sugars (I am fond of panela and jaggery). 1lb of panela would boost my 12lb example up to 1.080. And if I really want to get heavy, just boiling/dropping the final volume down to 4 gal gets me to a whopping 1.100 gravity.