BIAB Efficiency

Anyone ever get 90-93% brewhouse efficiency with BIAB?

These were my results on my last 2 batches only (that are currently still fermenting - one prior thread mentions possible astringency with very high BIAB effeciencies). I was previously getting 75-78% effeciency but switched from a 60 minute mash and a single sparge to using an 80 minute mash and 2 (each 1/2 mash volume) sparges.

I'm planning to get a refractometer as a means of confirming that the numbers are true mash/sparge efficiency and not just spurious numbers from other factors. But in the meantime, has anyone else ever gotten such high numbers?

I usually get 82-85%. I use a 50-60 min mash (depends on how impatient I am that day) and then a 10-15 min dunk sparge.

I used to squeeze my BIAB quite a bit, and got efficiencies in the high 80s/low 90s. In lower gravity (<1.050) batches this was a fine practice, but I noticed in higher gravity brews, even with tight temp and pH control, I was getting husky astringency.

Since then I've nailed the astringency down to bits of grain and husk getting into the boil kettle. I switched to a lauter-in-bag setup with my bottling bucket so I could vorlauf to filter the runnings. The batches I've done that way have much better head retention, mouthfeel, clarity, and flavor than my previous method.

I do lose efficiency that way, dropping down to the mid-70s, but the end product is so much better I don't care.

Could you explain your vorlauf method?

Nateo said:

I used to squeeze my BIAB quite a bit, and got efficiencies in the high 80s/low 90s. In lower gravity (<1.050) batches this was a fine practice, but I noticed in higher gravity brews, even with tight temp and pH control, I was getting husky astringency.

Since then I've nailed the astringency down to bits of grain and husk getting into the boil kettle. I switched to a lauter-in-bag setup with my bottling bucket so I could vorlauf to filter the runnings. The batches I've done that way have much better head retention, mouthfeel, clarity, and flavor than my previous method.

I do lose efficiency that way, dropping down to the mid-70s, but the end product is so much better I don't care.

Click to expand...

Interesting.


I have never squeezed and in fact I hate holding up the bag to drain after the mash so much that I usually only hold it up for a minute or so. Then I put the grain bag in a second pot with sparge water, stir to mix the grain with sparge water. Then I let it sit 10 minutes in the pot. Is this the same way you used to sparge?

I have not noticed husks in the wort...

I mash on the stove-top in a regular pot without a bag. Just grains and water.

I take my bottling bucket, put in a 5-gallon paint strainer bag, secure it around the "spout" of the bucket with some 1" webbing and a cam buckle. After I'm done mashing, I add some boiling water to bring the mash temp up to 165* or so, and I pour all of the mash from the pot into the bucket.

I draw off about 1 liter of wort and slowly pour the wort back over the mash grains while the second liter is draining. I repeat this until it's not heavily clouded. Once it's not cloudy, I'll collect the wort in my kettle. Then I'll dump the sparge water in, and repeat the process.

It takes me about 30-45 minutes to recirculate both the mash and sparge to where it's not heavily clouded. On a saison I went for about 1-1/2 hours and the wort was perfectly clear, though this is probably not necessary or desirable unless you want really, really high attenuation.

I've read that people with proper mash tuns can achieve this in 15 minutes or so. I think If I just made a proper false bottom for my bottling bucket I could get similar results.

This process catches a tremendous amount of grain and keeps it out of the boil kettle. I used to have 2-3" of sludge on the bottom of my fermenters after primary, now I only get a very thin layer of trub.

Really interesting.

I always wondered if there was a way to emulate pouring the initial run-off back into the grain bed. I guess that does it.

I have had some chill haze issues. Maybe I'll have to do something similar if the issues persist after some recent changes.

Thanks.

So, in short, it sounds like 90-93% is possible but not necessarily good. I'll have to see how my batches turned out with this effeciency. The great thing is that one of the batches was a 1.058 and the other a 1.098. So I'll also be able to see the effects on different gravity beers.

Yeah it's kind of interesting that "higher efficiency means better" is the conventional wisdom. The only time I think it's better is if you own a brewery and you're trying to squeeze out as much wort per dollar as you possibly can. On my scale, the difference between 75% and 90% efficiency is about a pound and a half of grain, or $1.50 because I buy in bulk. In the grand scheme of things, not that big of a deal. That's not even half a pint bought at a bar.

My method isn't as good as a proper, dedicated MLT setup, but it uses only equipment that I currently have, which is why I got into BIAB in the first place.

Agreed on efficiency. I did not try to get better efficiency. I was really just changing my mash/sparge process in an attmpt to fix other things. I ended up way overshooting my intended OG. I wanted a 9% beer that looks to be finished fermenting at 10% or so.

My issue is that I'm not sure what to assume for my next brew.

So I'll just go with my plan of getting a refractometer and adjusting from there.

Tagged

what are you using for a grain bag to get husks in the boil kettle? I really don't see how any husk can get through Voile. I'm not knocking the way you brew since I firmly believe that there are as many valid ways to extract the wort as there are beer styles... just wondering what type of bag you use so others that use the same type bag might check to see if they have husks in the boil.

I do an Aussie style BIAB. I mash for an hour, then raise the temp to 170 for a 10min mashout. This helps out quite a bit with efficiency. I then pull the bag and sit it in a colander that sits on top of my kettle. It sits there draining while I'm bringing the wort to a boil. Once boil is achieved, I remove the bag from the top of the kettle and proceed as normal. I don't do any type of rinsing and achieve around 70% efficiency, which is completely fine with me.

Mysticmead said:

what are you using for a grain bag to get husks in the boil kettle? I really don't see how any husk can get through Voile. I'm not knocking the way you brew since I firmly believe that there are as many valid ways to extract the wort as there are beer styles... just wondering what type of bag you use so others that use the same type bag might check to see if they have husks in the boil.

Click to expand...

If I am reading the prior post accurately, he doesn't use a bag for the mash portion? This is why I think he gets husks.

But I have read through older posts which mention astringency with high BIAB efficiencies.

Either way, I think the idea of filtering the initial run-off with BIAB is interesting.