I, too, now worship at the BIAB altar!

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maltoftheearth

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Yesterday was my first attempt at a BIAB brew and it was fantastic -- with one exception. I'll start there.

My only problem was the loss of water. I started with 6 gallons and ended with maybe 3.5 or 4 (at best.) The grains absorbed a TON of water and there was way more boil off than expected.

That said, I was able to compensate by adding boiled and cooled water to the wort at the end of the process in order to achieve my desired gravity (1050.) So, the only negative is not knowing exactly how much wort I have at the moment -- I think maybe 4.5 gallons.

The pluses = greater temperature control of the mash and greater ease of use. It was so much easier to step up my mash temperatures, I had not been doing that but I am going to do it every time now b/c it is so much easier than messing with a mash tun.

I am off to read some other posts about BIAB by members here but I wanted to include my process for critique:

I loaded up my brew pot with 6 gallons of water, carried it outside, dropped in the grain for my Hefeweiss, heated up to 112 (according to Radical Brewing some mash at this temp for 30 minutes to get a greater clove taste) for 30 minutes and then mashed at approx 153 for 90 minutes. Then I lifted out the bag (ungodly heavy), set it on a strainer, got the wort to a boil, boiled for 60 minutes, then dropped in the wort chiller.

***Grain Bill***
5lbs hard red winter wheat (germinated and malted by me)
5lbs American 2-row pale malt
.25lbs Munich Malt (10L)

75% efficiency would have been 1052 at 5 gallons. I hit 1060 at 3.5 or 4 gallons. Since I am not convinced the wheat was crushed very well I am very happy with these results!:ban:
 

Kaz

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I usually try to end up with 6.0 gallons after the boil. That being said for a batch like yours, I start off with about 32-33qts. After the mash, I squeeze the heck out of the bag, or put a grill over my kettle and use the kettle lid to press a lot of the wort out of the grain bag. I usually end up with about 7.25-7.5 gallons after mashing and squeezing, then I find my boil off gets me to about 6 gallons. Only problem is in my 10 gallon kettle, any more than about 12lbs of grain with 33qt. of water is going to overflow. Gotta work out that kink for bigger beers. All in all, sounds like you had a positive BIAB experience, I've never had a bad one, makes me wonder if I'll ever buy a mash tun. Good Luck!
 
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maltoftheearth

maltoftheearth

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How do you calculate your water/grain ratio for BIAB? If BeerSmith had the BIAB option then I would totally use it but alas, without sparging and with all this water loss that software is now far less useful for me.
 

thughes

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Do a 10 minute mashout at 168-170 and then squeeze the snot out of that bag when you pull it.

As far as water volume, I use a simple formula:

total water volume required = desired batch size + (#'s of grain * .08 gal absorption) + (gal/hr boil off rate * boil time) + kettle loss + fermenter loss - starter volume.

You will have to adjust your absorption rate based upon how hard you squeeze the bag and what the grist consists of (corn and rice absorb more than grain....found that out the hard way).

You will also have to adjust boil-off based upon your rig.
 

Zamial

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I am not trying to poopoo your fun but I was under the impression that squeezing the bag releases tannins.
 

Kaz

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Do a 10 minute mashout at 168-170 and then squeeze the snot out of that bag when you pull it.

As far as water volume, I use a simple formula:

total water volume required = desired batch size + (#'s of grain * .08 gal absorption) + (gal/hr boil off rate * boil time) + kettle loss + fermenter loss - starter volume.

You will have to adjust your absorption rate based upon how hard you squeeze the bag and what the grist consists of (corn and rice absorb more than grain....found that out the hard way).

You will also have to adjust boil-off based upon your rig.
+1 I use about the same formula, I usually disregard starter volume. If you get Beersmith V.2, it does have some BIAB functionality and mash profiles.
 

eastoak

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How do you calculate your water/grain ratio for BIAB? If BeerSmith had the BIAB option then I would totally use it but alas, without sparging and with all this water loss that software is now far less useful for me.
the new version of beersmith has BIAB options.
 
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maltoftheearth

maltoftheearth

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Do a 10 minute mashout at 168-170 and then squeeze the snot out of that bag when you pull it.

As far as water volume, I use a simple formula:

total water volume required = desired batch size + (#'s of grain * .08 gal absorption) + (gal/hr boil off rate * boil time) + kettle loss + fermenter loss - starter volume.

You will have to adjust your absorption rate based upon how hard you squeeze the bag and what the grist consists of (corn and rice absorb more than grain....found that out the hard way).

You will also have to adjust boil-off based upon your rig.
Thank you! That is exactly what I need -- if only I understood everything in your formula:

* is there a "standard" boil off rate? I think mine is about 1gal/hr but I have never measured, maybe that is too much?
* what is "kettle loss"
* what is "fermenter loss"
* wouldn't you add, rather than subtract, the starter volume?
 

JWS

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How do you calculate your water/grain ratio for BIAB? If BeerSmith had the BIAB option then I would totally use it but alas, without sparging and with all this water loss that software is now far less useful for me.
Try this, it's worked awesome for me:
 

bschoenb

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The Key to BIAB is to know how much water you need at the start of the boil for your end result; I need 7.75 gallons to give me a 1.5 gallon boil off and 6.25 in the kettle after boil. I started BIAB with that notion and topped off my kettle prior to boil and adjusted my effeciencies obtained by my grind as well as the grain absorption ratio using Beersmith2. Within' three batches, I've got it dialed in perfectly w/BS2... Effeciency is 75%, Grain Absorption is 1.1 (with a light squeeze and 10 minute dripoff). Works perfect...
 

thughes

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Thank you! That is exactly what I need -- if only I understood everything in your formula:

* is there a "standard" boil off rate? I think mine is about 1gal/hr but I have never measured, maybe that is too much?
* what is "kettle loss"
* what is "fermenter loss"
* wouldn't you add, rather than subtract, the starter volume?
- boil off rate: 1gal/hour is a good place to start, varies with vigor of the boil, surface area of liquid, ambient air temp and humidity, etc. This is something you will dial in over several batches as you "learn" your rig.

- kettle loss: the amount of liquid left in your kettle after you drain everything. If you're going to dump everything into the primary (which is perfectly fine to do) this value will be zero. I normally whirlpool and get all but the last 1/2 gallon of clear wort into the fermenter.

I'll run that last 1/2 gallon (mostly hops and break material) through a filter and then freeze what wort I get out of that mess to use for future starters. ;)

- fermenter loss: the amount of liquid and crap left behind in the fermenter (s) when you racked the finished product into the bottle bucket or keg.

- if I am going to pitch a 2 qt starter I need to subtract that volume otherwise I will end up with 2 more quarts of finished product than I had originally planned on (which isn't really a bad thing).
 

frailn

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Welcome to BIAB! I, too, had a struggle with how much water to use. But, after four or five BIAB brews, I got smart and started paying closer attention to things like absoprtion rate, boil off rate, etc...Just means more brain work and preparation before hand. What I discovered is that it is more practical with my set up to do smaller batches.

I was trying to do five gallon batches, but now, I'm only going to do three gallon batches until I can buy a bigger kettle. Not worth the hassle to fight the system.
 

RIT_Warrior

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A few tips I've learned:

1. The absorption is horrendous. But I compensate by doing a "sparge". I rest a colander over my pot and pour hot water through the grains. I make a "hole" in the middle of the grains and aim for that while I pour, I find that seems to help the water distribute in a more even fashion. I also squeeze the crap out of the grains using a metal lid after the sparge is over.
2. For bigger beers, I just keep some DME on hand. If I miss my efficiency, or if there is just no way to hit my OG with my limited brew pot/grain bag setup, I just factor some DME into the equation. I rarely have to use it, and the most I've ever had to use is a pound.
3. I try to keep my mash as thin as possible, and I try to get my liquid/grain mixture as close to the top of the pot as possible without going over. This seems to help me get better efficiency and also helps compensate for grain absorption. It also helps keep my mash temperatures steady.
4. Crush the **** out of your grain. If your LHBS or online retailer is crushing for you, get a Corona mill and crush them yourself instead. To calibrate, I crush the grain until I'm scared at how fine the result is, and then I give it another quarter turn. There is no such thing as a stuck sparge in BIAB, and your bag is fine enough to keep anything you don't want in the batch out. Efficiency is key for me because of the limited amount of grain I can mash.
 

TopherM

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I also did my first BIAB on Saturday. I did DeathBrewer's SMASH APA. I have been brewing since December and have 13 extract batches under my belt, including two hard ciders.

At the advise of the Aussies on the BIAB forum, I used the trial version of ProMash for my brew day. I was a little skeptical of the water volumes calculator in the program that told me I needed around 8 gallons of water to end up with 4.94 gallons post-boil, but I followed all of the ProMash numbers and came out with just a bit over 5 gallons and a 74% efficiency. That was with a 4 gallon BIAB mash at 158 degrees, then basically batch sparging with the additional 4 gallons at 170 by pouring it through the suspended bag after the first big squeeze to rinse the grains.

I'd recommend trying out ProMash for your next batch. It doesn't have BIAB-specific calculations for everything, like BeerSmith II, but as long as you use some common sense as to which numbers don't apply to BIAB, it is a very very useful tool.

I might try to trail version of BeerSmith II for my next BIAB and report back how that works out.
 
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