BIAB, why is my efficiency so high?

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zacster

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I know this is a problem you'd all like to have, but I'm new to this and don't understand what I'm doing different than everybody else that I get high efficiency.

My batch yesterday gave me an 89% efficiency according to Beersmith, and my prior batch was around the same in the end. I lift the grain out, let it drip into the pot, then squeeze out the last of it into another pot and pour it into the main kettle, then pour some wort over it and squeeze it out again. That's all I do. It doesn't sound all that different. I have the homebrew store grind it all extra fine. I stir the mash to get it mixed in, and stir when bringing the temp up to mash out.

What am I doing wrong or right?
 
I'm curious how fine your crush was. I am also curious more about your process. Starting gravity, grain bill, mash temp & duration.. etc...
 
Other than asking to go extra fine on the crush I don't know how "extra fine" it really is. Maybe that's it, but if it were that easy wouldn't we all be doing that?

I'm trying to figure out how to paste my recipe from Beersmith, nothing I'm trying gives me good formatting. I'm on a Mac if anybody has any advice.
 
Your math is messed up, or your measurements. Or you are sparging.

Let's assume the following, and I think these are good assumptions:

  • 0.2 gallons per # of grain stays in the grain, lost because you don't sparge
  • 10# of grain for your 5 gallon batch
  • Boiloff = 1 gallon

So, you add 8 gallons of water, and get 6 gallons of wort at the end of the mash. You've lost 2/8 of your sugars, still trapped in grain.

The max efficiency in this case is 75%. I don't know how you would get around that.
 
That's just a bad assumption. I added 7 gallons of water and ended up with 6.6 before the boil. That's a lot less loss. It didn't make sense to me as I expect to lose more. In fact I have more sitting in my primary 6.5 gallon carboy than will fit in my 5 gallon secondary.

I'm also not doing any math. Beersmith is doing it all. I'm just plugging the numbers in and following its method.

I'm just perplexed by the result.
 
That's just a bad assumption. I added 7 gallons of water and ended up with 6.6 before the boil. That's a lot less loss. It didn't make sense to me as I expect to lose more. In fact I have more sitting in my primary 6.5 gallon carboy than will fit in my 5 gallon secondary.

I'm also not doing any math. Beersmith is doing it all. I'm just plugging the numbers in and following its method.

I'm just perplexed by the result.

Just wondering, how do you take your water measurements?
 
My measurements are by the sight glass on my Blichmann. Reasonably accurate as Blichmann generally knows what they are doing.
 
Perhaps. It comes from Ray Daniels, Design Great Beers.

[edit: now that I think about it (should have done that first), I usually lose about 2 gallons on a 10g batch, which in the example above would be 1g or 0.1g per # of grain]

If you're saying you lose that much on a 10lb BIAB batch, then I'd say squeeze it more! I only lose about .1 gal per lb of grain (if even that much), but I squeeze the heck outta the bag!
 
I lose more like .05-.08 gal/lb in my biab setup. I brewed up EdWort's Haus Pale today, mashing in with 8 gallons and ended up with just shy of 7.5 gallons going into the boil. I do squeeze the bag lightly by twisting it up.
 
I also BIAB and I get 81% efficiency pretty consistently. It confuses me cause I heard that BIAB was less efficient. I do squeeze the bag(lauter) and rinse some in extremely hot water though admittedly its minimal. Has anyone figured this out?

edit: sorry for zombie thread raise...
 
I just hit 80% mash efficency with my BIAB. 90 minute mash. 8 gallons of water. 10 lbs of grain. Assumed 0.2 loss to trub and the same to grains. No sparge, just twisted the bag so it would hold itself closed and put it over a turkey fryer pot. I didn't ask for a special crush just used what the brew store crushed it at for me. pH started at 5.8 and dropped to 5.0 over the 90 minutes. No need to buy a cooler or mash run anymore. The $7 bag IS my mashtun
 
I've seen as high as 95 with smaller beers. I've also noticed like a 10 percent efficiency jump from the same batch, only differences is lower PH. ~5.2 compared to ~5.4
 
I know this is a problem you'd all like to have, but I'm new to this and don't understand what I'm doing different than everybody else that I get high efficiency.



My batch yesterday gave me an 89% efficiency according to Beersmith, and my prior batch was around the same in the end. I lift the grain out, let it drip into the pot, then squeeze out the last of it into another pot and pour it into the main kettle, then pour some wort over it and squeeze it out again. That's all I do. It doesn't sound all that different. I have the homebrew store grind it all extra fine. I stir the mash to get it mixed in, and stir when bringing the temp up to mash out.



What am I doing wrong or right?


Have you compared a malt analysis for the grains that you are using against the numbers for that specific grain in BeerSmith? Beersmith's grains are pretty generic and I found that almost all of the base malts that I use end up having a different potential. Some are more significant than others. This will affect your gravity because BeerSmith is calculating your gravity based on numbers that are not specific to your grain. It will make your expected efficiency incorrect because BeerSmith is calculating your efficiency based in an incorrect potential. This won't change your efficiency by some huge amount like 10% or so, but it could knock off a few points if BeerSmith's values are lower than your actual malt analysis.

See the pictures below. In BeerSmith, the field "Yield" should match your malt analysis' field "Extract % finely ground malt, dry basis". If not, then BeerSmith will calculate your grain's potential sugar extraction incorrectly, thus, giving you an incorrect efficiency. This could be just a contributor to why your efficiency is unusually high (it was for me until I figured this out). Although, there are probably other factors as well, as others have mentioned in previous posts.

ImageUploadedByHome Brew1391489770.867882.jpg

ImageUploadedByHome Brew1391489883.246358.jpg



Sent from my iPad using Home Brew
 
OIC, BeerSmith is calculating based on an average expected extract, whereas my actual malt may be higher or lower. I wonder how many users even pay attention to this detail.

OTOH, putting in the numbers doesn't actually change the brew if you are using a recipe, it just tells you how you've done. If I were building a recipe to hit a certain number this would be important.
 
OTOH, putting in the numbers doesn't actually change the brew if you are using a recipe, it just tells you how you've done. If I were building a recipe to hit a certain number this would be important.

It is important if you are using premade recipes as well. A recipe that someone else made will be based on their efficiency, which could differ from yours. Your grain amounts will change depending on the difference between your efficiency and the original recipe's efficiency.

For example, lets say a recipe has an OG of 1.081 with 82% efficiency and 14lbs of grain. If your efficiency is 89% then you will need less grain or else you will overshoot your OG. This is where the malt analysis numbers in Beersmith come into play. If your numbers are wrong in this field then your efficiency won't match Beersmith, and as a result, your actual OG and efficiency will be off. Your efficiency might actually be 87% but your grain bill would be based on an 89% efficiency. Not a big deal but it will affect your OG by a point or two. It could by worse if your malt number are way off buy that's unlikely.

I wonder how many users even pay attention to this detail.

Not saying that you or anyone else on here is a bad brewer, but I truly feel that it's little things like this that separate the exceptional brewers from the many great brewers out there. Consistency is important and this is part of that battle.
 
Yes, but if I buy my grain based on a recipe, I'm not going to adjust the quantity because my efficiency may be higher or lower. I guess this gets into the consistency you speak of. I do a yearly cycle of brews, so last year's batch may be different from this year's, but who is going to remember that?

I'm usually just happy that it comes out as a drinkable beer, although I'll admit that as I make more and get better at it I'm disappointed if it doesn't come out the way I wanted, such as low alchohol, low aroma, high bitterness, whatever...
 
Yes, but if I buy my grain based on a recipe, I'm not going to adjust the quantity because my efficiency may be higher or lower.

I don't mean to sound rude, but that is a really bad habit if you are doing already made AG recipes. It is ESSENTIAL that an AG brewer adjust the amount of grain to make up for the difference of efficiency between a recipe's and his/her own. Think about how far off your brew will be from the recipe if your efficiency is 89% and the recipe is 60%? Your OG won't even be close and you will come out with a different beer entirely. If a recipe says 8lbs of grain for 60% eff then you need way less grain for 89% eff. Not making this adjustment is just like using 11 lbs of extract when a recipe calls for 8 lbs.

Anyways. I'm not trying to call you out or anything. Just trying to help with efficiency problems.
 
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