BIAB Efficiency

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I'm an old school all grain brewer who has just recently came back to the addiction! Since I'm moving to smaller batches (1.5 maybe 2 gallon batches) and use the BIAB method. My question: What do I have to do to maximize efficiency? I have a love of Mild Ales and Brown Ales. I'd like to do what I can to make sure they do not turn out watery and 2 dimensional.

I appreciate any and all advise. I'm going to try and document my recipe development in this thread.

I'm so ready to do this, I feel like it's Christmas.
Thanks y'all.
Lee
 
My question: What do I have to do to maximize efficiency? I have a love of Mild Ales and Brown Ales. I'd like to do what I can to make sure they do not turn out watery and 2 dimensional.
Water adjustments: what is your plan to adjust the water for a good mash?
 
Thanks. That's what I had thought, but couldn't confirm. I want to copy English water as close as possible and thought a clean slate was the way to go.

Just what I'm looking for.
 
Mild Ales and Brown Ales. I'd like to do what I can to make sure they do not turn out watery and 2 dimensional
Did you have a couple of recipes in mind? If you can post them, there's a couple of people active here here who may be able to offer ideas on how to avoid the watery / 2 dimensional concerns.
 
I've got several style guides, but mainly working out of the Milds book. Due to the low grain bill, especially on Pale Milds, body and complexity can get lost. I adjunct with flaked wheat and other additives, but trying to sort through the endless assortment of yeasts looks to be a considerable chore.

Here's an example of one of my Bitters:

Boil Size: 2.17 gal
Post Boil Volume: 1.67 gal
Batch Size (fermenter): 1.50 gal
Bottling Volume: 1.40 gal
Estimated OG: 1.041 SG
Estimated Color: 8.3 SRM
Estimated IBU: 29.5 IBUs
Brewhouse Efficiency: 72.00 %
Est Mash Efficiency: 76.8 %
Boil Time: 60 Minutes

Ingredients:
------------
Amt Name Type # %/IBU Volume
1.13 g Gypsum (Calcium Sulfate) (Mash) Water Agent 1 - -
1 lbs 8.6 oz Pale Malt (2 Row) UK (3.0 SRM) Grain 2 64.6 % 0.12 gal
9.0 oz Honey Malt (25.0 SRM) Grain 3 23.7 % 0.04 gal
2.5 oz Mild Malt (4.0 SRM) Grain 4 6.5 % 0.01 gal
2.0 oz Wheat, Flaked (1.6 SRM) Grain 5 5.3 % 0.01 gal
0.37 oz Goldings, B.C. [5.00 %] - Boil 60.0 min Hop 6 26.3 IBUs -
1.00 oz Styrian Goldings [5.40 %] - Steep/Whirlpool 2.0 Hop 7 3.2 IBUs -
1.5 pkg British Real Ale (Brewtek #CL-0150) [8.87 ml] Yeast 8 - -

It's a little more bitter than I like, so I might adjust it down a bit, but I've gone as far as I can until I actually brew it and see the result.

I was also considering a little higher mash temp. This was something I spotted in one of James Spencers Basic Brewing videos. About 156 degrees or so.

Thanks folks. I appreciate the help.

Lee
 
Buy a mill and set it to the tightest setting.

This...

w/ BIAB you can crush almost to flour... stuck sparge isn't a major concern...

Biggest efficiency boost I got was getting my own mill... even double crush at the LHBS wasn't enough...

Ugly-junk corona mill can be made for $30-40... My Ugly Junk- Corona Mill Station...
 
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Thanks.

My local shop will mill to very fine setting. They are a trustworthy and knowledgeable shop.


Still probably not as fine as you can get away with using BIAB....

My LHBS actually bitched about self-serve double milling due to wear on the mill and extra flour gumming up the works :rolleyes:
Got my own corona mill soon after and started buying mail order grains.... Hardly ever go back to the LHBS now... Oopsie... nice customer service :p

Your shop most likely isn't going to tighten the mill gap between customers for BIAB vs traditional mash tun.... You'll definitely get a finer crush w/ your own mill...

As good as their crush is, you can go finer....


edit to add:

Plus having your own mill makes easier to buy grains in bulk and brew on your own schedule...
 
Sounds like something I'm gonna have to check out. They've always bent over backwards to help. Will have to see. I've been looking at mills, may have to get serious about it. Will also have to see about a very fine bag too.
 
@wilserbrewer here on this site makes awesome bags... Highly recommended...

I think if your peruse the BIAB forums, you'll see many folks recommending a much finer crush than the LHBS
provides in order to boost efficiency. But you can always add a bit of 2-row to up the OG when you have lower efficiency, too...

Consistency is more important than absolute efficiency.... Even adding 1 lb of 2-row to each brew to account for lower efficiency will take quite a few brew sessions to equal the cost of the cheapest mill set up...

So if you're not ready (or inclined) to mill your own, adding a bit of extra base malt solves the "problem" with your LHBS crush...

Brewing software is your friend in figuring out your efficiency and how to "hit your numbers"... I use Brewtarget... Others swear by BeerSmith... BrewersFriend is affiliated w/ this forum, I think... Many options available that can help you figure out which direction to take...

No single way is the best for everyone.... But I still like my ugly-junk mill ;)
 
I like that mill too. Fits my sense of style!! :bigmug:

I got started with Brewsmith and StrangeBrew many years ago. I've already updated Beersmith and am happy with it.

I've got extra Maris Otter and 2 row on my shopping list. Just in case I may need it, but I've gotta get this first brew day out of the way and see where I stand. I'm going to make a list of everything in this thread and incorporate it into the session so I can repeat it.

Using those bags, how much trub are you finding in the kettle? Do you use a tube?
 
Since you have more "flour" to start, you do get a fair amount of trub after the boil... I do stovetop BIAB, with overnight "no-chill"... I don't have a valve on my kettle, so I pour freehand into a bucket fermenter... i "try" to leave some trub behind as I pour but I still get a fair amount into the fermenter... yeast food ;) ... I find that it generally drops out with the yeast at the end of fermentation and I'm still able to get fairly clear beer...

I'm not super picky about clarity, though...

Sure, I definitely point it out when I end up with a super clear result, but I drink it all the same when it's not as clear as it could be... :p

Time and cold temps solve a lot of clarity issues...
 
My question: What do I have to do to maximize efficiency? I have a love of Mild Ales and Brown Ales. I'd like to do what I can to make sure they do not turn out watery and 2 dimensional.
My 2 cents: Go to slightly larger batches, like 2.5-3 gallon. Why? I've found that too small of a mash doesn't have much thermal mass and its more difficult to maintain a steady temperature. I get high efficiency by using the batch size in the mash (example 2.5 gallons) and then putting the evaporation and grain absorption water in a side pot, (about 2 gallons) heating that and do a dunk sparge/stir in the side pot. For some reason I get higher efficiency doing this instead of a full volume mash. But your results may vary.
Making sure the beers aren't watery is going to be somewhat dependent on your recipe and ingredients, but having a nice steady mash temperature can also play a role.
I also dump into the fermenter by hand, which is way easier with small batches, and I account for an extra 1/2 gallon or so of trub/hops when I'm figuring my total water volume. Sometimes if I'm being really cheap, I'll dump the 1/2 gallon of trub into a sanitized glass jug, let that settle and then add a pint or two of extra wort to the fermenter.
 
My dietitian says yeast is good for you anyway, so thats going for us!

Back when I was doing 5-6 gallon batches, I got spoiled on a power siphon. I thought I'd get a small one for this setup. Here in the Ozarks during the summer, the batch would NEVER cool off! So I'm also shopping for a MiniFridge to solve that issue.

I'm not above using finings or gelatin to clarify, but I'd rather not if I can do anything beforehand.
 
do a dunk sparge/stir in the side pot. For some reason I get higher efficiency doing this instead of a full volume mash.

kinda makes sense... depending on the expected OG... Once the diffusion of sugars into the full volume of water reaches equilibrium nor more sugars will be extracted... pulling the bag and dunking in fresh water will start a new round of diffusion of the sugars out of the grains...

So I can see how partial volume plus dunk sparge can lead to better efficiency than full volume...

The real question is whether the small increase in efficiency is worth the hassle of a separate dunk sparge ;)

Full disclosure: I dunk sparge since I can't comfortably* do a full volume mash for the OGs I brew...


* Which means I probably could but it's so close to top that I'm a-skeered, so I'd rather dunk in an extra 1.5 gallons. :p
 
My 2 cents: Go to slightly larger batches, like 2.5-3 gallon. Why? I've found that too small of a mash doesn't have much thermal mass and its more difficult to maintain a steady temperature. I get high efficiency by using the batch size in the mash (example 2.5 gallons) and then putting the evaporation and grain absorption water in a side pot, (about 2 gallons) heating that and do a dunk sparge/stir in the side pot. For some reason I get higher efficiency doing this instead of a full volume mash. But your results may vary.
Making sure the beers aren't watery is going to be somewhat dependent on your recipe and ingredients, but having a nice steady mash temperature can also play a role.
I also dump into the fermenter by hand, which is way easier with small batches, and I account for an extra 1/2 gallon or so of trub/hops when I'm figuring my total water volume. Sometimes if I'm being really cheap, I'll dump the 1/2 gallon of trub into a sanitized glass jug, let that settle and then add a pint or two of extra wort to the fermenter.

I had thought about that, and have decided to stay with 1.5-2 gallon batches. I have a couple coolers converted too mash tuns, 3 gallon and 5 gallon. Being an old Navy Machine Mate, I'm not worried about having equipment to clean. Doesn't bother me at all, if it accomplishes what I'm after. These coolers hold temp really well and also provide easy access to stir the mash occasionally.

But 2-3 gallon batches really are too big for me. I live alone and my brother might drink one once in awhile. I'm cursed with living in an area where everybody has no idea that there is better brew than that "stuff" from St. Louis.
 
I have 3 kettles, so a full boil is no problem. I have even thought about a 90 min boil. Maybe an option to try at a later time.
 
My 2 cents: Go to slightly larger batches, like 2.5-3 gallon. Why? I've found that too small of a mash doesn't have much thermal mass and its more difficult to maintain a steady temperature. I get high efficiency by using the batch size in the mash (example 2.5 gallons) and then putting the evaporation and grain absorption water in a side pot, (about 2 gallons) heating that and do a dunk sparge/stir in the side pot. For some reason I get higher efficiency doing this instead of a full volume mash. But your results may vary.
Making sure the beers aren't watery is going to be somewhat dependent on your recipe and ingredients, but having a nice steady mash temperature can also play a role.
I also dump into the fermenter by hand, which is way easier with small batches, and I account for an extra 1/2 gallon or so of trub/hops when I'm figuring my total water volume. Sometimes if I'm being really cheap, I'll dump the 1/2 gallon of trub into a sanitized glass jug, let that settle and then add a pint or two of extra wort to the fermenter.
For small batches, there's a good chance you can fit your vessel in your oven set to about 150°-160°F. This will minimize any heat loss due to low thermal mass of a small batch.

Mash efficiency is equal to conversion efficiency times lauter efficiency, and brewhouse efficiency is equal to mash efficiency times fermenter volume divided by post-boil volume. So maximizing mash efficiency means maximizing conversion efficiency (100% is achievable), maximizing lauter efficiency (100% is not possible.) Maximizing brewhouse efficiency means maximizing mash efficiency, and minimizing volume loss in the transfer from the BK to the fermenter.

100% conversion efficiency means you have converted all of the available starch into sugars and dextrins. You can directly measure conversion efficiency using the method here. If you aren't getting 95% or better conversion, you should look first at going to a finer crush, then at mashing longer. Crush primarily affects the rate of conversion, because gelatinization of starch grits must occur before the starch can be acted on by amylase. So, gelatinization is the rate controlling step in conversion. Gelatinization starts at the surface of the grain grits, and proceeds towards the center, thus smaller grits completely gelatinize faster than larger grits, and therefore complete conversion faster.

Mash temp also affects gelatinization rates, with gelatinization occurring faster at higher temps. So, all else being equal a lower temp mash will convert slower than a higher temp mash, and will require a longer mash time to complete conversion. If the mash temp is too high, then you risk denaturing the enzymes before they can complete their work.

pH has a relatively small effect on gelatinization rate, so plays less of a role in conversion efficiency than most people think.

Lauter efficiency depends on how much of the sugar you created in the mash gets left behind with the spent grain. You increase lauter efficiency by reducing the grain absorption rate (by extended bag draining and/or squeezing the bag), and/or sparging the grain after initial draining/run-off (sparging rinses sugars from the spent grain grits.) Lauter efficiency can be predicted if grain weight, water volumes, grain absorption rate, and sparge details are known. The chart below shows the maximum achievable lauter efficiency for different grain weight to pre-boil volume ratios, grain absorption rates, and number of batch/dunk sparge steps.

Efficiency vs Grain to Pre-Boil Ratio for Various Sparge Counts.png


0.12 gal/lb is the typical absorption rate for a traditional MLT, and what you might see with a short bag drain using BIAB. 0.06 gal/lb is what can be achieved with a moderately aggressive bag squeeze. Long draining alone can get you in the 0.11 to 0.08 gal/lb absorption rate. You should measure the absorption rate for your particular process in order to be able to predict mash efficiency.

Lauter efficiency is increased by decreasing the grain absorption ratio, and/or adding sparge steps.

Brew on :mug:
 
Thanks doug, that gives me something to chew on. James Spencer touched on that in an email he sent me today. I've been going over a couple of books to narrow this down, but I think they're a bit long in the tooth, but Charlie has touched on this a time or 2.

I'm starting to think that using the MLT to maintain the mash temp, even though it may not generally be needed, may make the big squeeze more attainable and therefore help attain an grain absorption rate to a glorious .06.

Every time I read your post I get a little more out of it. Thanks.
 
This...

w/ BIAB you can crush almost to flour... stuck sparge isn't a major concern...

Biggest efficiency boost I got was getting my own mill... even double crush at the LHBS wasn't enough...

Ugly-junk corona mill can be made for $30-40... My Ugly Junk- Corona Mill Station...

jt, has anyone done a tutorial on setting up a corona mill? I'm seriously looking at getting one in preparation of the next round of brew trials.
 
For small batches, there's a good chance you can fit your vessel in your oven set to about 150°-160°F. This will minimize any heat loss due to low thermal mass of a small batch.

I was just about to mention that. It works great for 1.5-2 gallon batches when you can fit your kettle right in the oven. I turn my oven on the "warm" setting while I'm getting up to strike temp, then after I mash in it goes right into the oven and I shut the oven off.
 
Thanks rat, I just realized that thread had 54 pages!!!!!

Looks like I got some reading to do.

I'm a big fan of my Corona mill. Hand cranking 5lbs for a typical batch is an easy 10 or so minutes. I've done up to 13lbs, that was a chore.

Pay attention to the mods which actually improve function. Getting the plates to run parallel, stiffening the bracket, etc.

When they talk about a 8/32 bolt, they really mean 8-32 machine screw.
 
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I'm a big fan of my Carona mill. Hand cranking 5lbs for a typical batch is an easy 10 or so minutes. I've done up to 13lbs, that was a chore.

Pay attention to the mods which actually improve function. Getting the plates to run parallel, stiffening the bracket, etc.

When they talk about a 8/32 bolt, they really mean 8-32 machine screw.
Roger that DB. Will keep that in mind.

Running small batch of Mild means small grain bills. :p:rock::rock::ghostly:
 
I'm gonna have to run some tests on my oven. It's 25 years old and I'm not sure how well it holds temps.

A BBQ thermometer takes out the guessing. Before switching to the anvil foundry I would have one probe in the mash and the second clipped to the oven shelf. The door stays shut. Just don’t fully submerge the probe in the mash, keep the cord above the water line.

I don’t super fine crush on my mill nor do I sparge (I do full volume mashes). Once I got past the idea of chasing efficiency and decided consistency was far more important I plug 65% into my software and am generous about leaving trub in the kettle and fermenter and let the software calculate. The extra grain for this works out to pennies per brew, but it also shortens my brew day and helps clear the beer.

I’ve have all my one gallon gear but I ended up 2.5 gallons as my default. It’s 20 pints. I like to brew about once a month and so as one kegs runs empty, the next one is ready to tap

oh yeah, mini kegs in a converted mini fridge kegerator rule as does a second mini fridge converted to a fermentation chamber. Talk about improving the quality of you beer.


fwiw I was using beersmith for years then gave brewfather a try. If you like using your phone or tablet on brew day and prefer to keep your laptop high and dry, the brewfather is better as it’s on a newer platform that works more seamlessly than BeerSmith over the cloud.
 
I'm gonna have to run some tests on my oven. It's 25 years old and I'm not sure how well it holds temps.
It won't matter how well your oven holds temp. The point of putting the mash tun in there is to minimize the temperature difference between the mash and the air outside. A 152 degree mash sitting in a 150 degree oven won't be losing nearly as much heat as if it were sitting in 40 degree air. Even if the oven is a little above or a little below the mash temp it will help a lot.

Now lets talk about mash period. The temperature of the mash is only critical during the conversion of the starch to sugar. Once all starch is converted, the temperature isn't at all critical. It could be anywhere from 100 to 190 degrees and still extract color and flavor from the grains. So now tell me, how long does it take for your mash to complete conversion. That is how long the temperature needs to be maintained. Hint: That time is dependent on how small the grain particles are. You can get full conversion with unmilled grain but it will take a very long time (look up the process for caramel malts) but as the particles get smaller the time for conversion goes down. You can verify this by using iodine to test the grains for remaining starch. It can be a fun experiment and an eye opener to do so.
 
It won't matter how well your oven holds temp. The point of putting the mash tun in there is to minimize the temperature difference between the mash and the air outside. A 152 degree mash sitting in a 150 degree oven won't be losing nearly as much heat as if it were sitting in 40 degree air. Even if the oven is a little above or a little below the mash temp it will help a lot.

Now lets talk about mash period. The temperature of the mash is only critical during the conversion of the starch to sugar. Once all starch is converted, the temperature isn't at all critical. It could be anywhere from 100 to 190 degrees and still extract color and flavor from the grains. So now tell me, how long does it take for your mash to complete conversion. That is how long the temperature needs to be maintained. Hint: That time is dependent on how small the grain particles are. You can get full conversion with unmilled grain but it will take a very long time (look up the process for caramel malts) but as the particles get smaller the time for conversion goes down. You can verify this by using iodine to test the grains for remaining starch. It can be a fun experiment and an eye opener to do so.
Correct me if I'm wrong: smaller batches means smaller thermal mass, which would mean a little more difficulty maintaining temperature control? Testing for conversion is a big tool on mash completion, which is another reason why I'm leaning towards my old cooler tun. Ease of access. I'm almost convinced it's the way to do this mash. I'm gonna try both ways and see where the ball bounces.

You guys have given me a whole lot to think about. I greatly appreciate it.
 
My overall suggestion is to jump in and figure out a process that works for you.

I tried my oven once for a 1 gal batch and it worked better than I expected. My lowest oven temp is 170F. I let the temp settle there and turned off the oven. The process of opening up the oven to add the pot likely cooled it down enough. As I recall, after an hour it was still very close to my mash temp. I have done other small batches (1 to 2.5 gal) wrapping them in a blanket or sleeping bag.

As far as efficiency goes...I never think that maximizing efficiency should be a goal. Yeah, it is probably good to get your efficiency above the 60% range. It is more important to understand your efficiency and to be able to consistently hit your efficiency. Then you can tune your recipes around your numbers.

I tune my 2.5 gal batches around a 70% efficiency, and find that with a good crush and a simple process I am able to hit that pretty consistently.
 
When I was brewing 5 gallon batches, my efficiency would run in the 70-75% range using a 3 vessel system.

The reason this is so important to me is because I'm brewing Milds. Milds have a nasty habit of turning out kinda flat and 2 demential. 2 things are the front line of turning out a good Mild, efficiency and including something to add a bit more protein. I plan on mashing at 156 degrees and adding malted rye.

I just got off the phone with my LHBS and they do a BIAB crush. But you have to ask for it. No charge.

Thanks guys. I've printed off this whole thread and all the links. This is all going into my work folder for reference as this project progresses.
 
I'm still a new brewer but 3 things boosted my efficiency after a couple of batch :

1- Keeping temperature steady ( I also use my oven :p )
2- As BIAB crush is very fine, make sure to not have any clump in it by mixing it very thoroughly before mashing
3- I mix it every 15 mins during the mash
 
I'm still a new brewer but 3 things boosted my efficiency after a couple of batch :

1- Keeping temperature steady ( I also use my oven :p )
2- As BIAB crush is very fine, make sure to not have any clump in it by mixing it very thoroughly before mashing
3- I mix it every 15 mins during the mash
Have you ever checked how long conversion takes. Once the starch is all converted to sugar the temperature and the stirring don't help. I used iodine and scooped a little grain to test it on because that is where the starch would be. Put a drop or 2 of iodine on the grain and see if you have starch left.
 
Have you ever checked how long conversion takes. Once the starch is all converted to sugar the temperature and the stirring don't help. I used iodine and scooped a little grain to test it on because that is where the starch would be. Put a drop or 2 of iodine on the grain and see if you have starch left.

Truth.

Once the conversion is over, thats the end of the mash. And brewing Milds that can end rather quickly.
 
Have you ever checked how long conversion takes. Once the starch is all converted to sugar the temperature and the stirring don't help. I used iodine and scooped a little grain to test it on because that is where the starch would be. Put a drop or 2 of iodine on the grain and see if you have starch left.

Not yet. Like I said, I'm still new. I'm adding this in my "to try" list :D
 

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