Brew In a Bag - What Efficiency Can I Expect?

I do BIAB. Depending on the strength of the beer typically determines my efficiency. For milds and bitters, I often get 75% efficiency, but with stronger beers it can drop to as low as 65%.

 

First, you need more total water than your preboil volume, because of grain absorption (and mash tun dead space if applicable). That said, given a fixed conversion efficiency (the amount of starches converted to sugars), you'll get the best possible mash efficiency (sugars into the kettle) for batch sparging if each step is be set up to run off equal volumes of wort.

For fly sparging, thinking about it makes my head hurt. So here...
http://braukaiser.com/wiki/index.ph...auter_Efficiency_.28Batch_and_Fly_Sparging.29

For BIAB dunking/resting/pseudo fly sparging, beats the hell out of me.

 

Is Jack stating that, if you brew in a bag but then employ any type of sparge, you're no longer Brewing In a Bag, even though you are brewing in a bag?

 

Me thinks so

Just to clear any confusion up for anybody, BIAB can be done with no sparge, with a traditional sparge, with a dunk sparge, and probably with some other really cool modern sparge technique I don't even know about yet!

 

My readings on the BIAB method are like what is written on the Brewer’s Friend website:

“After the mash is complete you heat the mash to mash-out temperature, which is crucial to achieving good efficiency with BIAB since you are NOT rinsing the grains.”

http://www.brewersfriend.com/2009/06/20/brew-in-a-bag-biab-all-grain-brewing-method/

I will take your word for it that the BIAB method can also include a sparging process.

Cheers!

 

What water to grain ratio are you looking for? I figured it at 1.33gt water/ lb grain.

 

O.K. I didn't recalculate it at 2qt, but if that is what you got then go with it. I've only done a few BIAB and I used 1.33. So, disregard my earlier comment.

 

My BIAB efficiency improved when I purchased a Barley Crusher. Now I crush my grain fine and efficiencies have improved dramatically. I'm in the mid 70s generally, and considering I'm still fine-tuning my crush I expect that to go up, hopefully....

 

Efficiency in BIAB really varies across the board. I'd give it a try and see where you're at. If you're coming in under 70% or so, I'd try running the grain through the mill twice to see if that improves your yields (this assumes you're buying it at a local place and not online, although I imagine NB or MB might do this on special request).

 

NB told me "no" when I asked. Midwest will do it if you ask, as will Austin Homebrew Supply

 

I use a modified BIAB that includes dunk sparging. Really, the only similarity my methods have to BIAB is that the grains end up in a bag for filtering because I have no other means of lautering. My extraction efficiency on small batches (2.5 to 3 gallons) is low 80's. It's not a pretty process, not very time efficient... but it works for me until I can get bigger volume gear.

 

The most important lesson is learning your system. ~65% efficiency isn't ideal, but it's better than 63% one batch and 75% the next. Consistency is great and it won't break the bank to add an extra pound of gran to each bill on a homebrew scale.

 

I am just learning so you can probably disregard the rest of this if you want. I've been doing BIAB for a few months now. I haven't calculated efficiencies much yet, but I feel they are pretty high. I have had inconsistencies as I am learning my system, but I have had a few O.G.s come in a good bit higher than the recipie's target O.G. I usually try to mash at 2qt/lb and dunk sparge with the rest. At first it was tempting to hold the bag up and pour sparge water to rinse the grains. But I *think* I have learned that any water used is best used to soak the grains in, you get more out of it. I haven't tried mashing with the entire volume like maybe a standard BIAB would be. Little worried about the high water to grain ratio with that, but I think the reason that works with BIAB is because the bag holds the grains close together. But again, I could be wrong I don't know much.