Help with BIAB technique

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hcaz999

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Ive done three batches with the BIAB method, and I tend to come up a little short on the SG readings (up to 11 points off)... I was wondering if any BIABers could help me out with improving my efficiency?
 
Batch size? Pot sizes? Grain amounts? Need details if we're going to spot any areas where you can improve things... What efficiency level are you getting?
 
This past batch was a dark wheat beer. Using beerformulator.com i got that my SG sould be 55, and I got only 44. I use a 10 gallon pot.

Batch size: 5 gals
Total Water: 7.8 gal

Pale Malt 2-Row (Muntons) 5lbs
German Wheat Malt 5lbs
Black Patent 1/2 oz
Crystal (60L) 4oz
mash for 80 mins at 150F-153F, mash out for 10 mins

I thought maybe I was using to much water?
 
Sparge??

I used a 32 and 20 quart pot for most of my BIAB batches... Mash in the 32 quart with 1.5-2qt/# of grain, then sparged in the other with the balance of the water. Combine both into the 32 quart get to a boil and continue as normal. Got 78-82% efficiency there.

Never used wheat malt before, so not sure if you need to do any different steps there. I've been using UK 2 Row malts (MO, GP, Baird's Pale Ale)...

Last batch that came close to your amount of grain was 10# (exactly) where my OG was 1.054, with a 79% efficency. I mashed with 2qt/# and spared with 2-3/4 gallons... Before that I used 11# grain (10# 2 Row, 1# crystal malts) and hit 81% for an OG of 1.064...

If you're not sparging, at all, that could be the issue. Get a second pot, or if your current pot has a ball valve installed, run off the mash wort and sparge. I usually sparge for anywhere from 10-30 minutes, depending on the recipe and a few other items... 10-15 minutes is probably plenty. DO make sure you fully drain the bag when you remove it. Otherwise, you're tossing away good wort.

Ran your recipe through Beer Smith... Looks like you're getting 57% efficiency there... That's just not right... At 75% you would have hit an OG of 1.058. Even at 70% you would have hit 1.054 (about where your target was)...

I mash for 90 minutes, just for reference... I also try to keep my temps within 1-2F of my target. At least for the first hour. My last recipe I did BIAB I mashed at 152-154 for 90 minutes, with a temp of 150 at the end of the mash...

Are you getting ALL the doughballs out of the grain bag?
What do you do when adding the grain?
I've found that if you put in ~1/2 the grain, mix it in, then add the balance, mixing it in to remove all clumping/doughballs, you'll get better results... I also stir the mash 2-3 times after getting the clumps out, checking the temp each time.
 
I do have a second pot and I've been thinking about using it (i think I remember a post on here about a 2 pot all grain method. I was under the impression (and ive seen from a couple posts here and videos on youtube) that sparging wasnt used.

I put in maybe .5-1 lbs of grain and stir it up to avoid doughballs...I stir every 15-20 minutes and I still am pretty new to AG but I dont think I see any doughballs.

One thing that I still have trouble with is keeping a constant temperature on my mash (this one started around 156F and dropped to about 146-148F over the course of the 90 minutes)

Do you think maybe the starting water volume is a little to much, and in essence diluting the wort?
 
I wouldn't mash with more than 2qt/# of grain... Use the second pot to sparge with.

I would also look to insulate your main pot. Either with high temp tolerant insulation wrap, a sleeping bag, heavy towels (top and sides) and/or a pillow on top (have heard it works really well). I wrapped my aluminum kettle in reflective insulation, which helps keep the heat inside the kettle. I also put a heavy towel on top. IF you're really careful, you can apply a small amount of heat to the kettle to help keep the temperature where it needs to be.

Dropping about 10F over 90 minutes is not good. You need to get that under control ASAP. Depending on the grain temp, air temp, you'll need to set the mash strike water temp to the right starting point.

I would use Beer Smith to figure things out. I've had excellent results using it so far.

I think you're just mashing with tons of water, that is all over the place for temps, so you're not getting a good mash. Try the "Single Infustion, XXXX body, No Mash Out" or "Single Infusion, XXXX Body, Batch Sparge" mash profile next.

With BIAB, you should be able to hit at least 70% efficiency... Of course, assuming your grain has a decent crush on it... Do you mill your own, or does the place you buy it from mill it? What is the mill set to for a gap? I was getting mine from a supplier that uses a gap of .039"... My Barley Crusher (used for the first time last Saturday) has the same gap on it... Getting over 70% efficiency every time that way.
 
One way to increase your efficiency is to mill your grain finer. If you are having your LHBS mill it, ask them to run it through twice.

A mash out step is also critical in maximizing efficiency. The higher temperature decreases the viscosity of the wort allowing for greater extraction.

There is no need to use multiple pots or do a sparge of any kind with BIAB. On lower gravity beers (1.050 and under), I routinely get 75-85% efficiency. Beers 1.050 to 1.060 achieve 70-75%. As the gravity starts exceeding 1.060 efficiency really starts to suffer.
 
Your water may be a bit high. I usually do batch size + boil off + (.1 or .06 * grain bill). So in your case it would be more like 7gal.

How big is your bag, can your kettle fit inside your bag?

Do you slowly bring your temps up and mash out? I don't sparge, but raising the temp on your way out will loosen up the sugars. I don't squeeze the bag just because I seem to be getting enough efficiency without having too.

Maybe once you can keep your temps locked in you will get better output. Can you turn the flame on to help out?
 
as far as the grain crush is concerned, i asked the LHBS to run it through twice to get a finer crush.

how long do you usually mash out for? I've been doing 10 minutes then leaving the grain above my pot to drain then squeezing whats left into a bowl or something and putting that wort back into the boil kettle.
 
There is no need to use multiple pots or do a sparge of any kind with BIAB. On lower gravity beers (1.050 and under), I routinely get 75-85% efficiency. Beers 1.050 to 1.060 achieve 70-75%. As the gravity starts exceeding 1.060 efficiency really starts to suffer.

That's pretty funny since I hit 82% on a brew with an OG of 1.072.
We hit 72% on a mutant mash process for a 10 gallon batch with an OG of 1.065 (this past Saturday).
I hit 79% on a brew with an OG of 1.054.
81% on a brew with an OG of 1.064.

I hit better efficiency when I had my water:grain ratio at 1.5-2qt/#. It all depended on how much grain I was using. I would mash with as much as I could, within my 32 quart pot, and make sure I could sparge in the 20 quart pot... Over 75% efficiency every time. I haven't brewed anything with an OG under 1.050, well, ever...

I don't think you NEED to double crush your grain, as long as the crush is good the first time. If it's NOT good, and they won't adjust the mill, then yes, have them run it through again to hopefully get a better crush of the grain.

I see this as one of the reasons so many all grain brewers get their own mill. You're no longer at the mercy of the LHBS, or online vendor. YOU get to set the crush to what works best for your system. If you don't get good results, then you figure out what to adjust until you do. Be that mash/sparge, crush size, mash time and temp, etc...
 
Another thing, when I heat my water to the calculated strike temp (in this case it was 172F) the way I introduce the grains into the pot, my water temp is never below 156F when Im all finished putting the grains in. Should I lower my strike temp?
 
Another thing, when I heat my water to the calculated strike temp (in this case it was 172F) the way I introduce the grains into the pot, my water temp is never below 156F when Im all finished putting the grains in. Should I lower my strike temp?

Unless you want to have full body brews all the time... Adjust the strike temp so that you can hit your desired mash temp. Another thing software should help you out with. I'm using Beer Smith, which lets you put in things like the grain temp, mash tun temp, etc. to get what you need to have your strike temp at in order to hit your mash temp.

Generally speaking:
154F+ is full body brews
150-154F is medium body brews
under 150F would be light body brews.

There are times, and brews, for all of the ranges. There are also times when you want to go higher, or lower, than the normal range. You might want to do a medium-light body brew, so you mash at ~151-152F. Or you want something on the boarder between medium and full, so you mash at 154-155F...

I think you really need to get a tighter control over your mash temps, and process. Get with some other all grain brews and see how they do things. If you're lucky, there will be at least one other person (in your area) that also uses the BIAB method.

Another part of your issue could be amount of head space in the pot when you mash. I try to get the least amount of head space in my mash, and sparge, pots when using the BIAB method. I'm talking about 1-2" MAX... Having the pots closer to full helps stabilize the temperatures. Insulating the pots also helps. IF you need to fire the pots, make sure you lift the bag from the bottom so that it doesn't get burned, and possible break open, spilling the contents into the wort.

Of course, you could try using an insulated bucket, and mash/sparge in that (with the bag made for large buckets)... I don't think that I could mash in that, but I could sparge in a bucket.

My next brew will have about 13-1/4# of grain to it (still finalizing the recipe)... I'm planning on using my cooler MLT for this batch, to see what I get for results. I might add some more grain, just to be sure I get closer to my target. I don't mind going over my OG, as long as things come out tasting good in the end.
 
That's pretty funny since I hit 82% on a brew with an OG of 1.072.
We hit 72% on a mutant mash process for a 10 gallon batch with an OG of 1.065 (this past Saturday).
I hit 79% on a brew with an OG of 1.054.
81% on a brew with an OG of 1.064.

I hit better efficiency when I had my water:grain ratio at 1.5-2qt/#. It all depended on how much grain I was using. I would mash with as much as I could, within my 32 quart pot, and make sure I could sparge in the 20 quart pot... Over 75% efficiency every time. I haven't brewed anything with an OG under 1.050, well, ever...

I don't think you NEED to double crush your grain, as long as the crush is good the first time. If it's NOT good, and they won't adjust the mill, then yes, have them run it through again to hopefully get a better crush of the grain.

I see this as one of the reasons so many all grain brewers get their own mill. You're no longer at the mercy of the LHBS, or online vendor. YOU get to set the crush to what works best for your system. If you don't get good results, then you figure out what to adjust until you do. Be that mash/sparge, crush size, mash time and temp, etc...

Not funny, just something different. The OP is using a different method than what you are familiar with. The BIAB being referred to is the one the Aussies started, here's a link. http://biabrewer.info

You do not use multiple pots or multiple bags. I have no doubt you are achieving those efficiencies with higher gravities, you are sparging.
 
Not funny, just something different. The OP is using a different method than what you are familiar with. The BIAB being referred to is the one the Aussies started, here's a link. http://biabrewer.info

You do not use multiple pots or multiple bags. I have no doubt you are achieving those efficiencies with higher gravities, you are sparging.

I'm using the BIAB method as outlined on THIS site, by DeathBrewer... That method IS with two pots, one for mash, the other for sparge. I'm not the only one getting solid results that way, across a range of OG's...

I found your comment of:
"There is no need to use multiple pots or do a sparge of any kind with BIAB." a bit funny, but also a bit wrong... There IS a need to sparge, IF you want to get steady, good results. If you don't care that your efficiency is all over the place, or drops as your OG increases, fine... Personally, I'm looking for more stability of results than have to increase the grain bill even MORE if I want to brew something with substance to it. As I also mentioned, I've never brewed anything with an OG under 1.050.

I'll use BIAB when I wish, but I also now have the option of using a cooler MLT... I'll be dialing on on that over the next few brews so that I can make a big brew with it. I'll need it since the grain bill will be over 20# for a 5 gallon batch (final volume)... I might be able to do it with BIAB in my 60 quart pot, pouring the mash into my 32 quart, but then I'll be struggling to get the sparge water up to temp... Far easier to simply mash in the cooler, drain the runnings into another pot, and pour the sparge water into the cooler. Combine both sparge and mash runnings into one pot (whichever one I need to for the initial boil volume) and set it to boil. I'm trying to get it so that I can sparge with the 20 quart pot, but I might need more water than that.
 
I'm using the BIAB method as outlined on THIS site, by DeathBrewer... That method IS with two pots, one for mash, the other for sparge. I'm not the only one getting solid results that way, across a range of OG's...

I found your comment of:
"There is no need to use multiple pots or do a sparge of any kind with BIAB." a bit funny, but also a bit wrong... There IS a need to sparge, IF you want to get steady, good results. If you don't care that your efficiency is all over the place, or drops as your OG increases, fine... Personally, I'm looking for more stability of results than have to increase the grain bill even MORE if I want to brew something with substance to it. As I also mentioned, I've never brewed anything with an OG under 1.050.

I'll use BIAB when I wish, but I also now have the option of using a cooler MLT... I'll be dialing on on that over the next few brews so that I can make a big brew with it. I'll need it since the grain bill will be over 20# for a 5 gallon batch (final volume)... I might be able to do it with BIAB in my 60 quart pot, pouring the mash into my 32 quart, but then I'll be struggling to get the sparge water up to temp... Far easier to simply mash in the cooler, drain the runnings into another pot, and pour the sparge water into the cooler. Combine both sparge and mash runnings into one pot (whichever one I need to for the initial boil volume) and set it to boil. I'm trying to get it so that I can sparge with the 20 quart pot, but I might need more water than that.

I know which method you are using, I was not confused. I never said there was anything wrong with that method. My intention was to assist the OP. Not sure why you are getting so defensive.

Once again I will reiterate that the OP is using a DIFFERENT METHOD than you. It is not wrong that you do not have to sparge. I agree that consistent efficiency is better than high efficiency. For 1.060 or greater beers, I do not use BIAB. I have a brutus system and usually brew 10 gallons.
 
for the OP.. you're not using to much water. you're doing a traditional BIAB following the aussie method. I do the same thing and hit 72-77%. after mash out stir the crap out of the grain. I also dunk the bag a couple times in the wort (not separate sparge pot) kind of like dunking a tea bag. drain it good and then make sure to squeeze every drop out you can.

btw.. how many gallons do you end up with pre-boil? how many to the fermentor?
 
Just a quick 2 cents. You said you are losing temperature. Do you cover your pot? I do deathbrewer BIAB technique usually with 1.25-1.5 q/pound. At 1.25 I lose almost no heat over a 60 minute mash with the pot covered and stirring every 15 minutes. FWIW I dump up to 12 pounds of grain into hot water all at once - not one pound at a time. I then stir and have never noticed clumping. For me this is faster than one pound at a time and I lose less heat that way.
 
I dont sparge and my lowest eff with the 5 BIAB brews I have made 75% the highest 78%. Traditional BIAB does not suggest sparging but even some of the Aussies have started to sparge. If your equipment is limited to smaller vessels and stove tops there really is no way around excpet for smaller batches <5gallons. If you have the vessel to hold 8-9g of water and grain for that size batch then no sparge is neccessary but you can sparge if you so chose. I also recommend a finer crush you do not have to worry about flour in BIAB as a matter of fact the more the merrier.
 
that's the beauty of brewing.. there are many different ways to accomplish the same thing. with traditional AG there are many ways of sparging. With BIAB there are many methods. some sparge, some dunk, some squeeze, some don't.. in the end, we all end up making beer..
 
for the OP.. you're not using to much water. you're doing a traditional BIAB following the aussie method. I do the same thing and hit 72-77%. after mash out stir the crap out of the grain. I also dunk the bag a couple times in the wort (not separate sparge pot) kind of like dunking a tea bag. drain it good and then make sure to squeeze every drop out you can.

btw.. how many gallons do you end up with pre-boil? how many to the fermentor?

I would say I'm ending up with about 6.5-7 gallons pre-boil (i dont have an exact measurement) and my last batch I ended up with about 5.25- 5.5 gallons of wort in the fermenter. I like to have a bit more so i can rack in into the secondary with as close to 5 gallons as possible
 
Just wrapped it around the pot once... It has an R3 rating I believe, so not high, but enough to help out... I did a test overnight with it. Starting at about 155-160F, it lost less than 10F overnight (12+ hours)... Of course, I put as much water in as I could, and put a heavy towel on the lid. I would make sure you use it someplace well ventilated the first time. If you can get something that can handle the mid 200F range (or above), get it. There's stuff listed on Amazon's site that is made for automotive applications, that is high heat tolerant. I would also advise leaving the bottom inch, or so, uncovered. Also leave at least 1/2" (1" would be good) from the lip of the pot free.

This is a picture of the kettle (the front one)... Doesn't show the sides as well, but should give you an idea...

2706-my-two-aluminum-brew-kettles-ball-valves-installed-back-one-60-quarts-front-one-32-quarts.jpg


Little bit better shot of the kettles...
2863-pots.jpg
 
If your pot will fit you could always slide it into your oven preheated to say 100F that should keep your temperature VERY steady. That is if your pot will fit.
 
If your pot will fit you could always slide it into your oven preheated to say 100F that should keep your temperature VERY steady. That is if your pot will fit.

I don't know of any oven that you can set to 100F... The lowest I've seen is 200F (which mine has as it's lowest setting)... To try and heat it up to ~150F will be a little tricky. Plus, getting it to hold that temp could provide other challenges.

IF your oven goes to 150F, then sure, use it. Otherwise, good luck in getting it to a safe temp for maintaining the mash temp without going over. Or losing what you need it to be at when you stir. Or having even temperatures for the time frame (can see it going all over the place as you try to get it where you want/need it).

Nice idea, but not as easy as you make it sound...
 
I would say I'm ending up with about 6.5-7 gallons pre-boil (i dont have an exact measurement) and my last batch I ended up with about 5.25- 5.5 gallons of wort in the fermenter. I like to have a bit more so i can rack in into the secondary with as close to 5 gallons as possible

you really need to have a way of getting exact measurements. as far as post boil. if you boil 6.5 gallon down to 5.5 gallons it won't have the same SG as boiling 7 gallons down. Again, 5.5 gallons will not give you the same SG as the recipe predicted if it was written for 5 gallons. all of that needs to be considered when calculating efficiency. as an example, at 77% efficiency a 5 gallon brew that has an SG of 1.065 would be 1.059 at 5.5 gallons. if I had 5.5 gallons and had the SG of 1.059 I would think my efficiency was only 69% when in reality I didn't boil it down enough to hit the numbers. But I wouldn't know that unless I knew how much I had pre-boil and post boil.

for what its worth.. I formulate all my recipes for 5.5 gallons at 72%. if I go high because I got great efficiency that's fine by me, if I get my volume correct then at 72% it'll be what I was shooting for and if I hit 70% that's OK too..
 
I don't know of any oven that you can set to 100F... The lowest I've seen is 200F (which mine has as it's lowest setting)... To try and heat it up to ~150F will be a little tricky. Plus, getting it to hold that temp could provide other challenges.

IF your oven goes to 150F, then sure, use it. Otherwise, good luck in getting it to a safe temp for maintaining the mash temp without going over. Or losing what you need it to be at when you stir. Or having even temperatures for the time frame (can see it going all over the place as you try to get it where you want/need it).

Nice idea, but not as easy as you make it sound...

My digital oven starts @155F I was not implying that someone use the oven to get to mash temp rather to maintain. If you are brewing stovetop get your mash up to temp on top cover slide in warm oven.
 
That settles it... My apartment/kitchen officially sucks on donkey parts... No, wait, it's not even that good.

My oven won't go below 200 either and wildly varies +/-50 degrees at any temperatures. Most ovens just aren't accurate enough. Even if you can get it down to 150, it might go up to 200 when the heat kicks in before the thermostat shuts it off. I tried mashing in my oven and it was not worth the effort of lifting a full 24 qt stainless steel pot into the oven. I use a sleeping bag wrapped around the pot now and it works great.

The other advice here is good. You can also get better efficiency with a decoction mash with BIAB. I've done two BIAB decoction mashes recently, with 1.092 and 1.098 gravity beers and I got between 85 and 90% efficiency on both of them. And that is sparging with only 6 qts for 10lbs grain!
 
Edited my post my oven starts at 155F not 55. No I would not recommend using the oven to heat the mash. Preheat oven to its lowest setting while heating your mash water on the stovetop. When oven reaches lowest temp even 200F turn it off. When mash reaches mash temp dough in lid on slide into oven. Opening the door will probably lower the temp well below mash temp. An insulated oven heated to say 100F would hold a mashtun temp way better than a kitchen counter.
 
My oven still sucks donkey private parts... Lowest it goes is 200F... If I go to use it above 250F, it ends up being 50F high all the time. Sucks DONKEY!!...
 
If your pot will fit you could always slide it into your oven preheated to say 100F that should keep your temperature VERY steady. That is if your pot will fit.

I tested my oven with 2 gallons of water in a 5 gal SS kettle - heated the water to 154 on the stove during which time I heated the oven using the Warm/Hold setting. water temp after 1 hour in the oven was 154! will be using partial mash BIAB tomorrow using the Warm/Hold oven setting
 
I don't know of any oven that you can set to 100F... The lowest I've seen is 200F (which mine has as it's lowest setting)... To try and heat it up to ~150F will be a little tricky. Plus, getting it to hold that temp could provide other challenges.
Heat oven to 200, turn it off and stick mash kettle in. It will hold temp very nicely.
 
I used to do standard mashes for years, using the oven to keep it warm duirng the mash time. I even would check it and stir it every 30 minutes just to make sure it was staying in the proper temp range. Plus stirring it helps with the effirciency.
 
Now my problem is with BIAB. I am having the same bad efficiency issue as the OP, only even worse. I do need to be able to measure how much wort I have in my 16 gal. keggle. I crush my own grains, and I crushed them really fine on the last three. Part of my problem is not boiling off enough, and I know that now. But even given that, my numbers really suck a$$. So here it goes........

8# 2 row malt
1.5# Munich malt
0.5# Carahell
0.25# Aromatic malt
7.85 gal mash water at 126* for protein rest at 122* for 30 minutes.
Didn't pull bag up high enough and melted two small holes in it &%#@$^&!!!! and didn't realize it until I pulled the bag out after the mash.
Raised temp to 151* for 90 minutes.
Pulled up bag and heated to mashout at 168*.
Just over 5 gallons into fermenter, 1.045 = 62%
__________________________________________________________________________

5.6# Munich malt
4# 2 rwo malt
22 qts water @ 158* - 60 minute mash at 151*
10.45 qts water @ 189* - mashout at 168*
no sparge
water volumes got screwed up and ended up with too much wort and didn't realize it.
Didn't boil enough off.
6 gallons into fermenter, 1.031 = 53%
_________________________________________________________________________

5.6# 2 row malt
4# wheat malt
0.70# Munich malt
0.28# crystal 40*L
4 gallons water @ 130* - protein rest 122* (forgot to monitor temp and it dropped way low)
2 gallons water @191* - sac. rest 153* (wrapped keggle in sleeping bag - worked great)
1.6 gallons water @195* - mashout 168*
Forgot to add the hops, and ended up boiling off more wort volume.
Had 4 gallons into fermenter, 1.042 = 45%
__________________________________________________________________________

11# 2 row malt
2# flaked corn
2# rice syrup solids (last 30 minutes of boil)
I brewed this a while ago and hit my numbers perfectly, 1.081 = 70%.
27.5 qts mash water.
60 minute mash at 151*.
Keggle wrapped in sleeping bag, only lost a few degrees (brewing in garage - 35*)
Pulled up bag and heated mash to 168*.
8 qts sparge water at 170*, dunked the bag several times and let it drain well.
This time I had about 5.5 gal into the fermenter, 1.070 = 65%. I was calculating this one wrong, but still missing by 11 points ?????

I am getting better, but I definitely have some volume issues that I need to be more exact on, and I MUST be able to measure how much is in the keggle during the boil. Nothing planned for a while, I have 5 brews going right now, not to mention four wines too. Your input is always welcome.
 
you really need to know the actual volumes. for example.. the last recipe you got 1.070 which accordion to beer smith for 5.5 gallons that is 68% efficiency. but if you bump up to 5.6 gallons it suddenly becomes 69%

for the crush. are you crushing the grains REAL fine? remember, with BIAB you can crush finer than when using a traditional setup (no stuck sparges). You also mentioned that you lost a few degrees due it being 35 in the garage. Mashing at 151 and losing a "few" degrees is a big thing to look at. what was the temp at the end of the mash? 145? 146? higher? lower? it makes a difference. You might have been to low to get good conversion. You could also try mashing for 90 minutes. if the temps drop a couple of degrees..add a little heat. stirring the entire time you are heating to avoid hot spots and to not melt your bag.
 
I regularly get 88-92% efficiency without any off flavor and my beer is crystal clear.

I grind my malt to the finest my barley crusher will go.
I use 12 gallons of water for the mash.
I dunk sparge 3 times.
Squeeze bag, dunk,Squeeze bag, dunk,Squeeze bag, dunk,Squeeze bag.
I add water up to 14.5 gallons boil and end with 12 gallons of good clean wort.

Cheers
 
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