First BIAB attempt - not sure what to think

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jsp1511

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Hey Guys

Did my first BIAB run today with a 35ltr Digiboil and *think* I have a decent wort after it all (its cubed at the moment and I'll let it cool then transfer to ferment and pitch yeast.

I started with 25ltrs, and end up somewhere around 20-22ltrs which is where i was expecting to land.

But one thing is bugging me - for one reason or another I could not get any sort of boil out of the digiboil (definitely got heated the water, as plenty of steam was coming off - and when I dropped the grain bag in I got foam across the top). Had both elements active, and just set the temp via control panel as expected.

As a test during the cleaning process i even tried to boil ~15ltrs of water as a test - and i still struggled to get any sort of rolling boil

Anyone who uses a Digiboil 35ltr - do you struggle to see a proper rolling boil?
 
Hey Guys

and when I dropped the grain bag in I got foam across the top
This bit worries me for starters. With BIAB (and with all all grain) you drop the grain bag in and mash in at between 62 and 70 degree depending on style for 60 mins, then raise the bag, drain and squeeze, then boil. After the mash, need a decent boil for 60 mins before chilling or cubing.
 
Someone has to ask, did you bring it to the boil before adding the malt?
I see someone has just as I started typing. Its a good question and the way it reads.

If you aren't getting a sensible boil it might be a good idea to meter the element (measure the resistance) low cost elements might say they are 2400W but are often a lot less and occasionally a lot more.
If you cant get a good boil in 15L I would be thinking seriously of talking to the supplier.
Mark

This is something I wrote a few years ago, it was designed for use with a 40L Birko urn, you might need to do some adjustments for batch size but the process should be fairly compatible.

Basic step by step guide to “Brew In A Bag” (BIAB)
The aim being to achieve a “standard” 22.5 L brew into the fermenter.
All of the water for the brew goes in at the start
We have the 22.5 L we want, the grain will absorb about 0.85 L/Kg, there will be a loss under the tap of 2 L, this is full of rubbish called Trub, evaporation will be about 10% of the start volume.
So we need 22.5 + 2 + (5.17 X 0.85) plus 10% or about 29 L plus evaporation roughly 3 L
  • Add 32 L of water to the urn
Heat the water to the mashing temperature plus a degree or two as you get close stir well and measure with a thermometer. Consult an online metric “Strike Water Calculator” to get the exact temperature.
  • Heat to 66-67oC (as per calculator)
The bag is now inserted into the Urn it acts like a liner and folds down over the outside.
  • Fit Bag
The grain is now filled in, this should be done in stages with some gentle stirring to insure even mixing of the water and the malt, this is called mashing in.
  • Mash In
Wrap the urn in some good insulation, old blankets, doona, foam or whatever is available and allow to stand for the time on the recipe (usually 1 hour), this is where the enzymes act on the starch and make sugars and it’s called Mashing
  • Mash
At the end of the Mash, the bag is lifted up and allowed to drain, there are several approaches to this step personally I put an A frame ladder on the table straddling the Urn; gather the bag and tie it with a piece of rope (sheep bend is the best knot); use the rope running over one of the rungs to hoist the bag. Liquid in the mixture of malt and water in the bag will drain back into the urn leaving the expended grain behind.
  • Hoist the Bag
Once the bag is clear of the urn and draining turn the heat on to full. The bag will continue to drain for some time, try to resist the temptation to squeeze the bag. There is a lot of condensed protein mixed with the grain, squeezing can cause more of them to end up in the Urn which will make more Trub and can reduce the quality of the beer. It’s fine to leave the bag over the Urn for most or the entire boil. Do Not fit the lid during the boil
  • Begin the Boil
Ones the boil is well established its time to add the first hop or bittering hop addition, the timing varies from recipe to recipe usually it’s 60-90 minutes, make a note of the time and plan for later additions, I use a simple countdown timer to remind me.
  • Add Bittering Hops.
0-20 minutes from the end of the boil there may be other hop additions, these and the time of their addition are listed on the recipe. Loosely these are referred to as Taste additions that give Hop Flavour and later ones called Aroma Additions
  • Make Taste and Aroma Additions as per recipe
5-10 minutes from the end of the boil we add Clarifying Agents these are available in many forms but all act to help Trub (rubbish) to settle faster, these are called Kettle Finning.
  • Add Kettle Fining’s
At the end of the boil, check that the right volume is left, this will be 22.5 L plus the 2 L that will stay in the Urn, if it’s a bit under adjust the volume with Boiling Water make a note of any adjustments, this information can be used to adjust your next brew, if your evaporation is higher or lower than anticipated make adjustments to the start volume next brew.
  • Check Volume is 24.5 -25L
To help all the trub collect in the bottom of the Urn we Whirlpool, this is simply stirring briskly to establish a good rotation of the body of the brew, natural vortex action will cause the Trub to collect in a cone at the centre of the urn. Avoid excessive splashing you don’t want to stir air into the brew.
  • Whirlpool
Fit the lid and allow the brew to rest for around 10 minutes, this gives time for all the Trub to sink to the bottom; we then drain down in to a Cube. The wort must be hotter than 80oC and ideally at around 90oC. The heat will pasteurise the contents of the cube killing any bacteria. The cube should be as full as possible, have the lid fitted securely and then laid on its side; this is so the most convoluted parts of the cube are exposed to sterilising heat. After 10-15 minutes turn the cube onto the other side insuring all the surfaces get good exposure to heat.
  • Cube
Leave until cool, this generally takes a day or so, because of the natural sterilising the brew can be kept in an unopened cube for up to a year.
  • Ferment
When you are ready to ferment, simply pour the contents of the cube into your fermenter, add the yeast, any hops that are listed as Aroma or dry hops can be added to the fermenter, these additions will be in a T-Bag, ferment as usual.
 
I got a small boil, but not the rolling boil like i would have expected. When I finished - I even put water in to clean it, and cranked the temp to 90 to see if i could get real boil but even that struggled. i'll try again with 10ltrs and see what happens @ 70 degrees

If that doesn't work I might have to get in touch with Kegland and see what they say - with what everyone says about Digiboils, I kind of expected better
 
Sorry but two people asked and you still didn't address it, were you trying to boil with the full grain bag in there? If the max temp on the digiboil is 90c you will never get a boil happening, the element is just going to keep cutting out before it gets to 100c
 
Missed that part - I set thermostat to 68 degrees, and let the water hit that temp before dropping the grain bag in (think it was somewhere around 3kg total).

I did just do a little test - set the thermostat to 105 degrees to see if I could get a boil and I could. I then dropped the temp on the thermostat to 70 degrees and the elements turned off (as you would expect) and boiling stopped (which again you would expect).

So exactly sure what is going on atm!
 
I got a small boil, but not the rolling boil like i would have expected. When I finished - I even put water in to clean it, and cranked the temp to 90 to see if i could get real boil but even that struggled. i'll try again with 10ltrs and see what happens @ 70 degrees

If that doesn't work I might have to get in touch with Kegland and see what they say - with what everyone says about Digiboils, I kind of expected better

Why would you expect water to boil with the thermostat set to 90c?
 
After you pull the bag wind your temperature knob up to the max, you can't get too much. As above, you won't get a rolling boil if you dial anything less than 100 deg.
 
Ok - Light bulb moment just went off and I've realised my idotic mis-understanding of the BIAB process and water boiling points etc.

My mashing in was fine - was just expecting a boil of some sort to happen when I did (which obviously it didn't happen because I'm well below the boiling point of water). And once I pulled the grain bag out - i thought i needed to keep that at ~68-70 degrees (which now I know I don't).

So new process will be:
Load kettle with water and bring to temp mash temp
Load grain bag in and let is mash for 60min.
After mash period - pull the bag and let it drain and sparge if needed
Then crank the heat and get a good rolling boil going
Then start adding hops etc as per hop schedule

Then transfer to cube for no-chill
 
Last edited:
Insulation makes a big difference i have a 50lt keg witb 2200 watt element insulated with 25mm yoga mat no problems with a solid boil up to 40 lt .
Used to take nearly twice as long to boil before the insulation fit out.
 
When I got the Digiboil I grabbed one of the neoprene jackets so all good there.

The entire problem was me mis-understanding the process and not thinking straight!

Hopefully have time this weekend to re-do the brew properly and see how it all goes (few other bits and pieces I'll do differently as well to clean up the process)
 
Someone has to ask, did you bring it to the boil before adding the malt?
I see someone has just as I started typing. Its a good question and the way it reads.

If you aren't getting a sensible boil it might be a good idea to meter the element (measure the resistance) low cost elements might say they are 2400W but are often a lot less and occasionally a lot more.
If you cant get a good boil in 15L I would be thinking seriously of talking to the supplier.
Mark

This is something I wrote a few years ago, it was designed for use with a 40L Birko urn, you might need to do some adjustments for batch size but the process should be fairly compatible.

Basic step by step guide to “Brew In A Bag” (BIAB)
The aim being to achieve a “standard” 22.5 L brew into the fermenter.
All of the water for the brew goes in at the start
We have the 22.5 L we want, the grain will absorb about 0.85 L/Kg, there will be a loss under the tap of 2 L, this is full of rubbish called Trub, evaporation will be about 10% of the start volume.
So we need 22.5 + 2 + (5.17 X 0.85) plus 10% or about 29 L plus evaporation roughly 3 L
  • Add 32 L of water to the urn
Heat the water to the mashing temperature plus a degree or two as you get close stir well and measure with a thermometer. Consult an online metric “Strike Water Calculator” to get the exact temperature.
  • Heat to 66-67oC (as per calculator)
The bag is now inserted into the Urn it acts like a liner and folds down over the outside.
  • Fit Bag
The grain is now filled in, this should be done in stages with some gentle stirring to insure even mixing of the water and the malt, this is called mashing in.
  • Mash In
Wrap the urn in some good insulation, old blankets, doona, foam or whatever is available and allow to stand for the time on the recipe (usually 1 hour), this is where the enzymes act on the starch and make sugars and it’s called Mashing
  • Mash
At the end of the Mash, the bag is lifted up and allowed to drain, there are several approaches to this step personally I put an A frame ladder on the table straddling the Urn; gather the bag and tie it with a piece of rope (sheep bend is the best knot); use the rope running over one of the rungs to hoist the bag. Liquid in the mixture of malt and water in the bag will drain back into the urn leaving the expended grain behind.
  • Hoist the Bag
Once the bag is clear of the urn and draining turn the heat on to full. The bag will continue to drain for some time, try to resist the temptation to squeeze the bag. There is a lot of condensed protein mixed with the grain, squeezing can cause more of them to end up in the Urn which will make more Trub and can reduce the quality of the beer. It’s fine to leave the bag over the Urn for most or the entire boil. Do Not fit the lid during the boil
  • Begin the Boil
Ones the boil is well established its time to add the first hop or bittering hop addition, the timing varies from recipe to recipe usually it’s 60-90 minutes, make a note of the time and plan for later additions, I use a simple countdown timer to remind me.
  • Add Bittering Hops.
0-20 minutes from the end of the boil there may be other hop additions, these and the time of their addition are listed on the recipe. Loosely these are referred to as Taste additions that give Hop Flavour and later ones called Aroma Additions
  • Make Taste and Aroma Additions as per recipe
5-10 minutes from the end of the boil we add Clarifying Agents these are available in many forms but all act to help Trub (rubbish) to settle faster, these are called Kettle Finning.
  • Add Kettle Fining’s
At the end of the boil, check that the right volume is left, this will be 22.5 L plus the 2 L that will stay in the Urn, if it’s a bit under adjust the volume with Boiling Water make a note of any adjustments, this information can be used to adjust your next brew, if your evaporation is higher or lower than anticipated make adjustments to the start volume next brew.
  • Check Volume is 24.5 -25L
To help all the trub collect in the bottom of the Urn we Whirlpool, this is simply stirring briskly to establish a good rotation of the body of the brew, natural vortex action will cause the Trub to collect in a cone at the centre of the urn. Avoid excessive splashing you don’t want to stir air into the brew.
  • Whirlpool
Fit the lid and allow the brew to rest for around 10 minutes, this gives time for all the Trub to sink to the bottom; we then drain down in to a Cube. The wort must be hotter than 80oC and ideally at around 90oC. The heat will pasteurise the contents of the cube killing any bacteria. The cube should be as full as possible, have the lid fitted securely and then laid on its side; this is so the most convoluted parts of the cube are exposed to sterilising heat. After 10-15 minutes turn the cube onto the other side insuring all the surfaces get good exposure to heat.
  • Cube
Leave until cool, this generally takes a day or so, because of the natural sterilising the brew can be kept in an unopened cube for up to a year.
  • Ferment
When you are ready to ferment, simply pour the contents of the cube into your fermenter, add the yeast, any hops that are listed as Aroma or dry hops can be added to the fermenter, these additions will be in a T-Bag, ferment as usual.

Thankyou for taking the time to write this out, just about have everything i need for my first BIAB brew and this makes the process a lot clearer.
 
Just got full circle on this - finally got around to having another go at BIAB, and this time was a lot smoother and straight forward.

Forgot to take a post-boil gravity reading (but got a pre-boil reading of what I think is 1.015-1.018). Got it cubed atm, and will be throwing it into fermenter + fridge in the next day or two with some 1056 American Ale yeast.
 
Forgot to take a post-boil gravity reading (but got a pre-boil reading of what I think is 1.015-1.018). Got it cubed atm, and will be throwing it into fermenter + fridge in the next day or two with some 1056 American Ale yeast.

Take a sample at transfer and measure your OG then (it doesn't have to be immediately after the boil, it can be anytime between then and pitching. You need to capture information like this..
 
Finally got this into the fermenter - have a post boil gravity for ~1.040. According to Brewersfriend, the SG should handed around 1.041 - so must have done something right to be close to on target!
 
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