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some questions about the BIAB method

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joshesmusica

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Been thinking about all of the process steps necessary to do a BIAB. Been reading up as much as possible, but still just want to get some things clarified before I start with this method.

I haven't done the jump to all-grain yet because I was convinced I didn't have the capacity to do sparges. Now I've read about the no-sparge, and am beginning to think I do have enough space. I understand this could lower my efficiency some, but at my scale I don't think a few percentage points is a big deal. i'd rather spend the few dollars to make up for it in grains. But with a full-volume mash, will it make a pretty thin mash?
I typically like all my ales with a bit of residual sweetness to balance the bitterness, what are some ways to make sure this happens?
If I wanted to make a bigger batch, and i theoretically would already have a thin mash, would it then be a bad idea to top it off?
How much space do you usually leave for the grains, so as to utilize all the space possible, but not spill over?
Why do people recommend double crushing the grains?
 
It sounds like you already brew, but before getting to your specific questions, here's a fairly basic small-batch BIAB instructional I wrote.

The thin mash thing doesn't seem to make much of a difference at all, I've even switched over to no sparge for all of my 5 gallon batches, the beers are great!

To increase the perception of sweetness, you can mash a bit warmer (154-158˚F), use more flavorful base malts in place of standard 2-row (Vienna, Munich), increase the amounts of crystal/caramel malts (try Honey Malt, it's amazing), and/or use lower attenuating yeasts (WLP002/WY1968 is pretty great).

Topping off doesn't seem to work as well with AG as it does with extract unless the wort you produced is high enough OG so that the top off water brings it down to target. I'm not a fan of this.

Checkout www.simplebiabcalculator.com to determine space/volume stuff, it's a cool tool.

Double crushing usually allows for better efficiency. Since I mill my own, I only single crush and still get great efficiency, but most LHBS' don't mill as fine as me, hence the recommendation to crush twice. What has also worked for me is stirring the mash every 20 minutes or so.

Cheers!
 
thanks Marshall, I guess i should've just emailed you directly! haha

why aren't you a fan of topping off with AG? As you stated, making a high enough OG that topping off brought it down to target is basically the same as what i've been doing with extract brewing. Does it give it a watered down taste?

p.s. how's the latest experiment write-up coming along? i've been anticipating seeing the results!
 
How big is your boil kettle? Thats what usually makes a difference in BIAB. If your BK is at least 7 gallons, you can make quite a few recipes out there. It would be large enough to mash to an OG of say 1.062 or so (12-13 lbs of grain). Above that and you can add DME or LME to increase gravity. If your BK is 10 gallon you can mash just about any recipe. If its a 5-6 gallon BK, that will be tough to work with. You can fill your mash tun to within a half inch or so without problems.

If you will not be doing any sparges, I would recommend heating the mash to 170F for a mashout (keep bag off of bottom while doing this), stir the heck out of it to rinse as many sugars into the wort as possible, then raise the bag. You would then want to drain as much wort out of the bag as possible, and figure out a way to squeeze it.
 
I point this out often, but please remember that a 5 gallon batch minimum is not a Law of Brewing.

If you have a 6 gallon kettle, you can easily do a 3 gallon BIAB with full volume mash. I used to do larger batches, but I realized that I would never buy two cases of a beer I had never tried. So why would I want to brew that many? I do 1.5-3 gallons at a time now and experiment a lot, and save the 5 gallon batches for tried-and-true favorites.

Back to BIAB... The low efficiency thing is a myth. Just crush well, stir well and often, and employ a gravity drain for a long time to recover wort. Squeeze the bag if you like, but I prefer not to "just because." I have a measured absorption of only 0.24 qts/lb with a 30 minute gravity drain, and no mash tun loss (of course). That's much better than mashing in a cooler with no ability to drain past the dead space.

BIAB is so easy that I suggest you prepare, but don't go nuts... and just try it. You'll quickly see how simple it is compared to a three vessel setup. There are far fewer steps and fewer variables to account for.
 
I I have a measured absorption of only 0.24 qts/lb with a 30 minute gravity drain, and no mash tun loss (of course).

Thank you for this data point. I have been hanging my bag for only about 10-12 minutes. I do squeeze the bag. But when I don't see any more wort dripping out at a reasonable rate, I call it quits and discard the grains. For the last three batches my grain absorption has been 0.26, 0.27, and 0.32 quarts per pound of grain. Error on that is +/- at least 10 percent. I was wondering how that compared to others and if I needed to wait longer for drainage. I can now say, for me, that the extra hang time isn't worth the little bit of wort. Your data point suits me very well. Thanks!
 
Glad to help you save time. :) There is definitely diminishing returns with waiting an extended time, but since I place the bag on a colander over a separate small pot and just proceed, I'm not waiting.

After draining the gross volume of trapped liquid from the bag, I place the bag on said colander and just leave it while bringing the wort to a boil. After getting the hot break and any first hop addition sorted out, I dump whatever has drained into the kettle and put the bag right back where it was. Usually I'll shuffle the grains around a little when I do that. I'll check it one more time during the boil and pour off the small amount that remains, then forget about it til clean up time.

Last time I did this, I weighed the drained bag and got the 0.06 gal/lb figure.
 
Been thinking about all of the process steps necessary to do a BIAB. Been reading up as much as possible, but still just want to get some things clarified before I start with this method.

I haven't done the jump to all-grain yet because I was convinced I didn't have the capacity to do sparges. Now I've read about the no-sparge, and am beginning to think I do have enough space. I understand this could lower my efficiency some, but at my scale I don't think a few percentage points is a big deal. i'd rather spend the few dollars to make up for it in grains. But with a full-volume mash, will it make a pretty thin mash?
I typically like all my ales with a bit of residual sweetness to balance the bitterness, what are some ways to make sure this happens?
If I wanted to make a bigger batch, and i theoretically would already have a thin mash, would it then be a bad idea to top it off?
How much space do you usually leave for the grains, so as to utilize all the space possible, but not spill over?
Why do people recommend double crushing the grains?

Don't worry about the thin mash. That is not a consideration with BIAB. pH can be targeted and adjusted in the same ways as with a more conventional mash. (if pH is your concern with regard to mash thickness?)

The size of the pot can help determine what type of BIAB methodology you employ. I have a pot with an 11gallon capacity (A 10gallon Megapot). This allows me to do full volume no sparge BIAB for 5.5 gallon batches up to an SG of about 1.08. (I have not gone over 1.065 yet in my target recipes so this is omewhat of a guestimate).

With a smaller pot your options without topping off or utilizing extract are
1: Do full volume no sparge but with smaller batches
2: Use less water for the mash and sparge to your desired preboil volume

As an example my last batch had an OG of 1.055
Strike water 7.6 gallons
Add 11lbs of grain (under 9 gallons of volume in the pot)
After mash the bag is drained and squeezed.
Preboil volume was 7.1 gallons (0.5 gallons absorbed by grains)
Post boil 5.7 gallons
Volume into FV was 5.5 gallons

This is a typical mash with this size of grain bill

Volume measures to 0.125 gallon can be easily made with this pot

I double crush. This allows easier extraction of fermentable sugars as there is no concern with a stuck sparge in BIAB. I use a double bag to retain as much grain particulate as possible.

check out my process in more detail in the thread below. Ideas I cobbled together from other people on the forum.

BIAB is fun, straight forward and a great way to do all-grain brewing. Best of luck

Grain 1.jpg


Volume Marks.jpg


Dough In 2.jpg
 
Lots of good advice from gavin and brulosopher. Only thing I have to add is that simplebiabcalculator isn't that good. It's very limited and you can't change grain absorption rate and the mashout feature doesn't seem well defined.

As always I recommend either using my online calculator at pricelessbrewing.github.io/BiabCalc or beersmith or the biababacus. As an alternative, the next best online calculator I have found was the spreadsheet at http://biabbrewing.com/ which I used until I found I needed to sparge.
 
ok so if i was going to try to do a full-volume boil, and no sparge, but wanted to get a little more OG out of it, would it be ok to top up the boil water? i only have a 19L pot, so adding more and more grains would be tricky I guess.
Beersmith supposes that I will have 3.48L grain absorption for 5.7kg of grain. Does this sound about right? with that amount it's telling me to mash with 13.92L of water, then I would kettle top up with 8L, then in order to get the amount that I would want, I would need to top off with 4 more liters. is all of that just going to work against me in the end?
 
The defaults in berrsmith are for traditional 3 vessel brewing. Grain absorption in BIAB is significantly lower. I'm working off 0.05 gallons per pound of grain.

I lift the bag place on colander and squeeze the bag till I reach my desired preboil.

If you are adding water after you lift the bag be sure to Sparge the grains and not just pour in water. This way you will extract more sugars while reaching your desired preboil volume. Sparge after squeezing the bag and squeeze the bag after sparging.

There are lots of ways to Sparge with BIAB.

This is what a squeezed grain bag looks like with 11 lbs of grain and absorbed wort (0.5 gallon approx). Ready for disposal

image.jpg
 
Math math math, numbers numbers numbers.... BIAB is easy - RDWHAHB, let's quick talking and get you brewing.

Heat 8 gallons to 160*F.
Grind very fine 12# base malt and 4oz assorted specialty malt. Put in bag.
Put bag in water, stir until you have even mash and no dough balls.
Put lid on pot and wrap with blanket, wait 60 minutes.
Remove bag from pot. Drain, squeeze, use a colander - or don't.
Start boil. Add 4 oz hops between 60 mins and flameout. Chill, pitch yeast, wait 3 weeks. Package.
* All measures, weights, temperatures and times are approximate. YMMV.

It doesn't have to be complicated. Make some beer. Get some experience. Take good notes and refine your process accordingly.
 
The OP says he has a 19L pot. So that's only 5 gallons. My two cents is to keep it simple and just cut the standard 5 gallon recipes in half for 2.5 gallon batches, or maybe multiply all the amounts by .6 and make 3 gallon batches. Do full wort boils, no topping up with extra water.
If all the water and grain won't fit in your pot, you can use a 6.5 gallon plastic bucket for mashing.
 
I recently started BIAB, very simply. It's turned out great! Lighter colour, better taste. I say, just start small and go for it.
 
The OP says he has a 19L pot. So that's only 5 gallons. My two cents is to keep it simple and just cut the standard 5 gallon recipes in half for 2.5 gallon batches, or maybe multiply all the amounts by .6 and make 3 gallon batches. Do full wort boils, no topping up with extra water.
If all the water and grain won't fit in your pot, you can use a 6.5 gallon plastic bucket for mashing.

Agreed, I didn't make the connection since it's in L and my brewing mindset is in gallons. If you only have a 5G pot I would recommend either getting another 5g pot and doing two side buy side brews and blending them or sticking to smaller batch sizes, or getting a bigger pot. By all means you can top off if you want to, but a 5g pot is pretty small for all grain let alone biab mashing in the pot.
 
Math math math, numbers numbers numbers.... BIAB is easy - RDWHAHB, let's quick talking and get you brewing.

Heat 8 gallons to 160*F.
Grind very fine 12# base malt and 4oz assorted specialty malt. Put in bag.
Put bag in water, stir until you have even mash and no dough balls.
Put lid on pot and wrap with blanket, wait 60 minutes.
Remove bag from pot. Drain, squeeze, use a colander - or don't.
Start boil. Add 4 oz hops between 60 mins and flameout. Chill, pitch yeast, wait 3 weeks. Package.
* All measures, weights, temperatures and times are approximate. YMMV.

It doesn't have to be complicated. Make some beer. Get some experience. Take good notes and refine your process accordingly.

BIAB is easy but then so is basic math. It's even easier if brewing software is used. By all means approach things however you want. There are as many approaches to brewing as there are to any other hobby. Personally I love tinkering with a recipe in the planning stage and tweaking my profile in beersmith to get ever greater precision to my process. I get great enjoyment from planning a brew carefully and having the final volume in the FV and the SG match that plan.

Plan the brew and brew the plan.

This is a good video I found prior to doing any BIAB myself of BIAB in a smallish pot. Probably bigger than the OP's. I reckon 3 gallons is doable in a 5 gallon pot without an overt risk of a mess.

</iframe>[ame]https://www.youtube.com/watch?v=0lPvk6poj6Y[/ame]
 
Math math math, numbers numbers numbers.... BIAB is easy - RDWHAHB, let's quick talking and get you brewing.

Heat 8 gallons to 160*F.
Grind very fine 12# base malt and 4oz assorted specialty malt. Put in bag.
Put bag in water, stir until you have even mash and no dough balls.
Put lid on pot and wrap with blanket, wait 60 minutes.
Remove bag from pot. Drain, squeeze, use a colander - or don't.
Start boil. Add 4 oz hops between 60 mins and flameout. Chill, pitch yeast, wait 3 weeks. Package.
* All measures, weights, temperatures and times are approximate. YMMV.

It doesn't have to be complicated. Make some beer. Get some experience. Take good notes and refine your process accordingly.

I understand your point, but I'm not a newb to brewing, and I don't have any plans to brew in the next week or two. So actually there's no rush to quit talking and get to brewing. In fact, I'm not really sure why anyone would even tell a newb to quit talking and get to brewing. I'm sure you meant well, but that's horrible advice that I believe will lead to poor practices for a newer person.


The OP says he has a 19L pot. So that's only 5 gallons. My two cents is to keep it simple and just cut the standard 5 gallon recipes in half for 2.5 gallon batches, or maybe multiply all the amounts by .6 and make 3 gallon batches. Do full wort boils, no topping up with extra water.
If all the water and grain won't fit in your pot, you can use a 6.5 gallon plastic bucket for mashing.

I do plan on doing smaller batches actually. Just curious how much I can get out of the equipment I have. My next step in brewing equipment is to start doing 8-9L batches and splitting those between two 5L fermenters. The reason why I'm asking so many questions is because I want to make sure to get this all-grain method down so that I can get consistency with my process, and then start experimenting. I love beer, and my main goal is to produce good beer than my family and friends will enjoy, but I'm also very intrigued by the experimentation aspect of the hobby. I don't mind doing partial mashes for my bigger batches (in fact at this point half my 19L batches are PM, half are extract with steeping), I'm just wondering how far I can take this method with the equipment I have.
 
thanks Marshall, I guess i should've just emailed you directly! haha

why aren't you a fan of topping off with AG? As you stated, making a high enough OG that topping off brought it down to target is basically the same as what i've been doing with extract brewing. Does it give it a watered down taste?

p.s. how's the latest experiment write-up coming along? i've been anticipating seeing the results!

I'm not a fan of topping off with AG because it's not as predictable/controllable, which I value. I'd be more inclined to scale down my recipe rather than top off.

Is this Texas Josh?
 
I understand your point, but I'm not a newb to brewing, and I don't have any plans to brew in the next week or two. So actually there's no rush to quit talking and get to brewing. In fact, I'm not really sure why anyone would even tell a newb to quit talking and get to brewing. I'm sure you meant well, but that's horrible advice that I believe will lead to poor practices for a newer person.

Well said. Couldn't agree more
 
My two cents is to keep it simple and just cut the standard 5 gallon recipes in half for 2.5 gallon batches, or maybe multiply all the amounts by .6 and make 3 gallon batches.

I did a 3G batch yesterday in my smaller (5G) kettle. Granted, it was a session ale (4 point something percent) so not a huge grain bill. The kettle was up to the top with the Full Volume Mash, but when I pulled the bag, it gave me more than enough room to work. I watched very carefully as the boil came up to 212 (in case of boilover), but all went well.

2.5 to 3G batches in a 5G kettle are very doable IMHO
 
I'm not a fan of topping off with AG because it's not as predictable/controllable, which I value. I'd be more inclined to scale down my recipe rather than top off.

Is this Texas Josh?

yeah that's a good point. and that's my main reason for going to AG of course, to get control over all the elements.

i'm from oklahoma, living in norway. i had emailed you about an experiment that it turns out you were already about to send to a panel.
 
yeah that's a good point. and that's my main reason for going to AG of course, to get control over all the elements.

I will just throw in a different opinion on the topping off issue - IME it works great and is just as reproducible as a regular batch. I regularly brew 3 gal BIAB batches in a 5 gal kettle, but occasionally want a 5 gal batch. I just calculate for a higher OG batch then top off in the fermenter - for example make 3 gal of a 1.083 beer and top off to get 5 gal of 1.050. I have done this for a number of my proven recipes and don't notice a difference in quality. I do max out in the mid 1.050's with this, and I haven't tried any really full bodied beers, mostly wheats, pales, low gravity belgians, etc. I also need to do a dunk sparge in a second pot because a full volume mash won't fit - you could do that in any vessel really like a bucket. But if you want to add one more choice to your options I would encourage you to try it.
 
... quit talking and get to brewing. In fact, I'm not really sure why anyone would even tell a newb to quit talking and get to brewing. I'm sure you meant well, but that's horrible advice that I believe will lead to poor practices for a newer person.....

I would never hesitate to tell a newb to brew beer. What I said was:
1. Make beer
2. Take notes
3. Refine process

Making beer is artisan work. It is a craft that has to be practiced and learned. Ideally for a new brewer, they can find a mentor to teach them. If I wanted to be a pro brewer, I would be looking for a job as an apprentice to a great master brewer.

No amount of reading forums, studying books, playing with Beersmith or memorizing BJCP style guidelines will ever replace practical experience. Will it help you grow and expand as a brewer, yes. But it doesn't replace experience. There is only one way to learn your equipment and refine your process. And that's making beer. The more batches you make, the better you will get.

Make mistakes, have fun, drink beer, make fewer mistakes next time.
 
I would never hesitate to tell a newb to brew beer. What I said was:
1. Make beer
2. Take notes
3. Refine process

Making beer is artisan work. It is a craft that has to be practiced and learned. Ideally for a new brewer, they can find a mentor to teach them. If I wanted to be a pro brewer, I would be looking for a job as an apprentice to a great master brewer.

No amount of reading forums, studying books, playing with Beersmith or memorizing BJCP style guidelines will ever replace practical experience. Will it help you grow and expand as a brewer, yes. But it doesn't replace experience. There is only one way to learn your equipment and refine your process. And that's making beer. The more batches you make, the better you will get.

Make mistakes, have fun, drink beer, make fewer mistakes next time.

absolutely, i'm all for hands on experience. but in the downtime between brews, people should be reading up and asking questions and talking. and you did discourage that. not everyone is going to be lucky enough to learn under someone, so that's why these types of forums are great. it's like learning under a bunch of head brewers all at once (you just have to have the wisdom to know when to not take some people's advice).
 
absolutely, i'm all for hands on experience. but in the downtime between brews, people should be reading up and asking questions and talking. and you did discourage that. not everyone is going to be lucky enough to learn under someone, so that's why these types of forums are great. it's like learning under a bunch of head brewers all at once (you just have to have the wisdom to know when to not take some people's advice).

What? Downtime between brews? That's when I sleep! :D

I agree that you need to read about brewing before you start, then brew, then read about what went wrong and learn from what mistakes you made, then brew again, trying to avoid the mistakes you made on that brew. Reading alone won' t make good beer, nor will brewing without understanding the process. It takes a bit of both.
 
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