BIAB efficiency question - 71% good? bad?

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cinderbike

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Hey everyone. I am on my fourth BIAB batch. I've been working on getting efficiency up and not sure exactly what I've been doing right/wrong.

On my first two batches, I got pretty bad efficiency, around 60%.

I realized afterwards I wasn't stirring the mash well enough and had doughballs, and also wasn't crushing my grain as fine as I've read you should with BIAB.

The 3rd batch I got 68% efficiency. It was a medium gravity (1.060 recipe).

Now on this most recent batch, I had a high-gravity (1.1) beer that ended up at 1.093, 7 points off, which if I calculated correctly gave me 71% efficiency.

Am I doing okay, or is there something wrong here?
 
I think you are doing fine. There is nothing wrong with 71% efficiency. I've been doing a bit better than that by grinding my grain until it looks like corn meal. Temperature control may have an effect too. I find that the top of my grain shows too cool and the bottom just right to too warm. Stirring seems to help even out the temperature.
 
Do you squeeze the bag? Some say not to, but I do, without ill-effect. Splitting the sparge water into two batches helps too. But I'd agree that the grind has the biggest impact on efficiency. I run my grain a couple times through my mill, and condition the malt first, along with squeezing, I consistently get 85% that way.

http://braukaiser.com/wiki/index.php/Malt_Conditioning

I also use about 1/8-1/4tsp lactic acid in my sparge water to lower the pH below 5.8, and keep my mash pH in the proper range. PH effects enzymatic activity, so if your pH is off, that might be an issue.
 
I got 67% during my first BIAB session last weekend. I didn't stir the mash a whole lot though as I heard this could cause oxidation ... but I did add an extra pound of the base grain than the recipe originally called for.

Should I be stirring the mash more frequently/vigorously when mashing with BIAB?
 
I'll stir my mash once or twice an hour. If you get a good even hydration, I don't think stirring is that important. If you have dough-balls in your mash, then the stirring would break those up, and would improve your efficiency.
 
I got 67% during my first BIAB session last weekend. I didn't stir the mash a whole lot though as I heard this could cause oxidation ... but I did add an extra pound of the base grain than the recipe originally called for.

Should I be stirring the mash more frequently/vigorously when mashing with BIAB?

stirring the mash is OK.. in fact its a good thing as it help gets the temps even from the top to the bottom. you don't want to splash it all over the place but a good stirring is a good thing.
 
I've done 2 BIAB full volume mashes with no sparge, stirred every 20 mins,
and no bag squeeze, just a 10 minute drip with
64% efficiency into the boiler both times. I'm happy
at 64% , I'll just calculate my future recipes to 64%.
I know I'm getting high quality wort with only first runnings,
and I'm well below efficiencies that could extract unwanted flavors.

One thing I learned that could help others is the grain absorbtion for
squeezing the bag versus non squeezing. I measured 0.10 gallons per pound
for no squeeze with a 10 minute drip in a strainer, if your gonna
squeeze that number has to be lowered, I've read to maybe 0.06 gallons
per pound with a good squeeze(not that I'd recommend it).

Bob
 
Hey everyone. I am on my fourth BIAB batch. I've been working on getting efficiency up and not sure exactly what I've been doing right/wrong.

On my first two batches, I got pretty bad efficiency, around 60%.

I realized afterwards I wasn't stirring the mash well enough and had doughballs, and also wasn't crushing my grain as fine as I've read you should with BIAB.

The 3rd batch I got 68% efficiency. It was a medium gravity (1.060 recipe).

Now on this most recent batch, I had a high-gravity (1.1) beer that ended up at 1.093, 7 points off, which if I calculated correctly gave me 71% efficiency.

Am I doing okay, or is there something wrong here?


I BIAB with sparge and always get 80-83% without exception, if you do not sparge 71% is pretty much the highest you should get.

I keep hearing all this talk about 'grinding finer' or whatever... what the heck are you guys using the grind, a rolling pin? I use a barley crusher - one run through on factory setting - and my extraction is awesome.

Anyway, if you add a quick sparge step (tea bag, hit 165-170 - hold for 10 mins, and the drain) you should top 80% consistently.
 
I did my first BIAB (true no sparge, no extra equipment to wash) this last weekend. I anticipated 70% for my recipe with a .125 gal/lb of grain for water absorption by the grain. I crushed my grains at my LHBS and was planning on running them through twice but didn't have enough time. Their mill is set for standard AG.

I pulled my grain bag and lightly pushed it against the side of the boil pot and then hand suspended in the air for about 30 seconds. I would say about 90% of the water drained out in that time. I tossed this into a bucket to throw out later. For fun I ended up hanging the bag off a door knob, but still in the bucket. It really only ended up draining out another quart or so (didn't use it). Next time I would calculate about .1 or a tad less per pound of grain.

I was only a couple of points off and BeerSmith calculated my efficiency at 76%.

I had some problems keeping my brew pot temperature consistent throughout the 60 min mash (aluminum and cold weather), but other than that it went great. I really want to keep doing this method (time).

The wort is pretty cloudy and there is going to be a lot of trub. Does anyone know if this will clear up considerably?

An AG friend of mine did BIAB the day before and he had 72% efficiency.
 
so far the last three I've done have had 70, 75, and 78%. The last time I squeezed the snot out of the bag. Stirring I think is definitely necessary at least initially, and probably after the mash is done. I think anything between 70-80% you're doing just fine. Anything outside that and most people will say you're doing something wrong.
 
For my last three BIAB batches (not counting the one that I F'd up with a cooler) I've been getting 78-82% efficiency... The last batch (82%) I stirred in the first 5# of base malt, got rid of the dough balls, then added the specialty grains, stirred in, then the rest of the base malt, stirred in... Took a temp reading, and started the timer... Checked temp/stirred every 15-20 minutes (had to heat slightly during the process, but only once)... Pulled the bag from the boil pot, drained it (used a large wood mixing paddle to support it and help drain it) and sparged in another pot... Drained everything I could from the bag out into the sparge pot and then boiled...

Way I see it, if I consistently hit a range I'll be happy. I've been formulating recipes with a 75% efficiency, so that even if I slip a little, I'll still be ok (for the recipe)...

Basically, once you have your method/process and hardware dialed in, to the point where you're getting a short range of efficiency, you're good.

My larger concern is getting the mash temps within the range I want for the brew.

You can always add some DME to the wort if you miss your target by too much... Or just accept what you get and still make something really good...
 
If we wanna get a good efficiency into the boiler measurment, we need an exact volume of wort in the kettle pre boil measurment. We don't need to do this every time, as long as the mash and lauter processes stay the same, but if we're not measuring pre boil wort accurately, then we're only estimating efficiency.

Bob
 
I really need to measure and mark my kettle, I'm always clueless until I transfer.

You can also just measure/mark your stirring spoon. I melted small notches in my plastic stirring spoon to indicate key wort volumes like 5.5 gals, 6-gals, etc.

I found with my equipment, I boil down to the 5.5-gals notch on my spoon and once cooled I have approx. 5.2 gals of wort remaining.
 
I have done four now, and my first three were in the high 70's, but today I only got up to 67. Full volume and no sparge, but this one was at 154 mash temp, all the other one's were 152 or less. mashing hotter shouldn't affect my efficiency so much right?

also what do you guys mean by dough balls?? I run my grain through a corona mill, and perhaps I don't grind it fine enough because I have never had this issue, maybe I'd get better numbers?? Does anyone have any photo's of said dough balls?

All tasty brews so far, much better than my extract batches for sure.
 
dough balls would be lump of grain that did not get mixed into the mash water very well leaving dry centers. think of it like dropping a cup of flour into a pot of water. it forms a ball that is dry inside and wet outside... that's a dough ball.

as far as the drop in efficiency. the temp shouldn't change anything. but you did leave out important info. like grain bill. on larger grain bills mine will drop. smaller grain bills it goes up.
 
consistency is more important than the actual number; if you are interested in being able to repeat results...

+1 - Just got my 2.5 gallon all grain setup and I'm trying to dial it in. Id much rather be able to repeat and spend another $2 or so on grain.

Additionally, a large beer in that gravity range (1.100) is going to have a lot lower efficiency than usual for most homebrewing setups. Mainly cause you aren't using as much water per pound of grain when sparging. So 71% for a BIAB at that gravity sounds pretty solid to me!
 
+1 to all who stated that consistency is more important than efficiency. I've been an avid BIABer for the last 5 months.... having close to 12 beers with this method under my belt. No sparge used on this end, and consistently hit between 74-75% efficiency. Fine crush, stirring about every 10 minutes, and draining/spinning/squeezing the bag after. Works every time. Sparging is not necessary at all!
 
I found that crush was the deciding factor in getting better efficiency in BIAB. Once I got my own mill, and started trying different crushes, I started improving efficiency into the high 70s. I'm hitting 76-78% consistently now, not sparging, and not squeezing my bag. However, after draining my bag above the kettle for a couple minutes, I then suspend it above a small pot to catch any additional runoff. I usually end up with another quart or so...
 
If you start squeezing the bag you'll find that you can extract another quart or more of really sticky, high sugar wort and that will increase your efficiency. I think you are leaving a lot of sugars by not squeezing.
 
RM-MN said:
If you start squeezing the bag you'll find that you can extract another quart or more of really sticky, high sugar wort and that will increase your efficiency. I think you are leaving a lot of sugars by not squeezing.

I used to squeeze, and I used to sparge the bag, and results were inconsistent. Remove them from the process and you gain consistency.
 
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